The evaluation of the efficiency of listed companies, using nonparametric methods: An empirical analysis of the Greek Information Technology sector

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     International Journal of Computer System (ISSN: 2394-1065), Volume 02– Issue 01, January, 2015

     Available at http://www.ijcsonline.com/

    1 | International Journal of Computer Systems, ISSN-(2394-1065), Vol. 02, Issue: 01, January, 2015

    The evaluation of the efficiency of listed companies, using nonparametric

    methods: An empirical analysis of the Greek Information Technology sector

    Apostolos G. Christopoulos, Ph.D.

    [email protected] National and Kapodistrian University of Athens

    Faculty of Economics

    Abstract

    The aim of this study is to evaluate the companies of the IT sector in Greece and to classify them according to their effi-

    ciency, using the non-parametric method Data Envelopment Analysis (DEA). The period of investigation covers the

     years 2006 - 2010 which is the era of development of IT services, before the beginning of crisis in late 2010 which af-

     fected the financial results of these firms. One of the most important questions to be answered by IT firms in recent

     years is whether their offered services deliver to them the maximum possible results. Measuring the efficiency of pro-

    duction systems is a key problem in this answer. The efficiency concept is related to the ability of a firm to transform theinputs consumed in generated output. The traditional parametric methods for measuring the efficiency are based on a

     production function which describes the formation of inputs into outputs in the production system. The DEA is a non-

     parametric linear programming method used to measure performance. This method calculates the limit of efficiency of

    a set of production units using a function that describes the transformation of inputs into outputs. This method sepa-

    rates firms into profitable and non-profitable, while it also calculates the efficiency of each firm using the most favora-

    ble conditions for each firm which makes DEA as one of the most popular methods of analysis.

     Keywords:  DEA, financial ratios, corporate efficiency, linear programming, information technology.

    I.  I NTRODUCTION AND LITERATURE REVIEW 

    In order to evaluate the performance of a firm to uti-lize its resources we use two basic measures, productiv-ity and efficiency. The productivity of a firm is given bythe index of the volume of its output production basedon the amount of the employed quantity of inputs. Itmay include either all inputs and outputs or a subset ofthem. Productivity varies depending on the productiontechnology, the technical efficiency of the examinedfirms or the external environment in which these firmsoperate. On the other hand, efficiency is the degree towhich the optimal use of resources for the production ofinputs at a given level is equal to the optimal use ofresources required to produce the output of a given

    quality. The examined firm is characterised by the termDMU (Decision Making Unit). This term is used inorder to include under a single framework all kinds of

     productive units (firm, region, sector, country). There-fore, a DMU is defined as an entity which transformsinputs N into M final products or outputs at a specifictechnology. The aim of a DMU is to maximize the prof-its of a firm which, inter alia are achieved by improvingits performance.

    Measuring the effectiveness of firms within a sectoris a key criterion for the productive performance of theentire industry. In modern economic research, the over-all effectiveness of a production unit consists of three

    sub-definitions:

    • Technical Efficiency (TE): refers to the ability of

    a production unit to operate (or not) at the limit of the possible outcomes of the used production technology.

    • Scale (size) Efficiency (SE): expresses the devia-tion of a technically efficient production plant by themost productive scale size (MPSS). MPSS is the pro-duction scale size wherein the average product producesa combination of inputs x becomes maximum. Specifi-cally, is the point of full technical efficiency with con-stant returns to scale. For a given production technologywith production function y = f (x), the SE efficiency is:

    where AP is the average product (or the average productivity) of input x and is given by the formula:

    • Allocative Efficiency (AE): refers to the ability ofa production unit to use its inputs in optimal quantities,given the market prices of these inputs and the produc-tion technology. In a simple form of a production unitwhich uses an input x (cost price w) and for the quantityof output y, the overall cost effectiveness (total costefficiency) equals to:

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     Apostolos G. Christopoulos et al The evaluation of the efficiency of listed companies, using nonparametric methods: An empirical analysis

    of the Greek Information Technology sector

    2 | International Journal of Computer Systems, ISSN-(2394-1065), Vol. 02, Issue, 01, January, 2015

    Where x * is the amount of inputs when the produc-tion costs is minimize.

    Therefore the mathematical formulation of the allo-cation efficiency is:

    Combined the technical and the scale efficiencies, theyform the productive efficiency (PE) while the combina-tion of all three efficiencies forms the economic effi-ciency (EE).

    To understand the DEA method, it is essential to

    make clear the concepts of inputs and outputs in the

    implementation of this methodology. To assess the

    efficiency of a firm in general, as inputs are considered

    the goods or services used for the production of finalgoods or services (raw materials, machinery, capital,

    labor, knowledge, energy etc). Inputs are also referred

    as factors of production and can be classified into three

     broad categories: land (natural resources), labor and

    capital. As outputs we consider the produced goods or

    services that are either consumed by end user, or arereused in the production process. Depending on the

    nature of the investigated sector there are different types

    of problems concerning the definition of inputs and

    outputs.

    The appropriate selection of inputs and outputs toimplement the DEA method is the most important step

    to get reliable results. The key questions are whichinputs and corresponding outputs can be used in order

    to ensure that the results are comparable. The most

    important inputs used for efficiency and productivity

    are the capital, labor, energy and raw materials among

    which capital and labor are the most usual inputs.

    Although such inputs look pretty clear, in real

    conditions they become quite complicated. For

    example, a firm’s IT division incorporates electronic

    data processing and other processes, such as electronic

     payments. However, if it these works are given for

    management to another firm, then it is involved in more

    than one input, such as capital, labor, energy and raw

    materials. Labor is usually divided between thenumbers of employees, the hours of work and the labor

    cost which includes salaries that vary depending on the

     position of employees or even depends on the

    geographical location of the firm. Employees are also

    divided in skilled and unskilled, experienced and not

    experienced etc.

    Capital is an equally important input. According to

    the literature there are different ways to calculatecapital. Typically, we can take into account the assets,

    namely buildings, machineries and equipment. Still,

    cash may be included. Very important is the life of the

    assets.

    From the above we can understand the importance of

    outputs and inputs for the calculation of the efficiency

    and productivity of the concerned firms. Furthermore,

    since firms do not always record a complete and detail

    the prices of inputs and outputs, there is a prospect of

    forming financial ratios of input/output using more than

    one output/input. In more detail, when we examine the

     profitability of listed firms, the right selection ofoutputs/inputs becomes very important for shareholders

    and investors but also for the lenders of the examined

    firms. Such ratios can be derived from the firm’s

    financial statements. Therefore, the evaluation of listed

    firms is important for both the investors and their

    lenders. The most common financial ratios are used dueto the information they provide, concerning the activity,

    liquidity, profitability, capital structure, investments and

    operating costs of the firm under examination.

    To measure correctly the effectiveness we must know

    the limit of the production technology on which these

    measurements are made. Thus, the primary goal in the

    measure of effectiveness is the identification of the

     potential limit of production technology. In the last 40years many methods have been developed for assessing

    the threshold of production capacity. The two most

     basic methods are:- The parametric approach, which uses econometric

    techniques for estimating the production technology

    threshold, (stochastic frontier),

    - The non-parametric approach, which uses linear

     programming techniques to determine this threshold

    (DEA).Both techniques use a frontier of maximum

     production to describe every potentially profitable

    combinations of input-output that can produce one unit

    at a specific time. The differences between the twocategories mainly concern the assumptions used to

    estimate the technological limit production and theexistence of random error. It is worth noting that the use

    of different methods leads to differences in measuring

    efficiency.

    The category of parametric models is referred as the

    Stochastic Frontier Analysis (SFA) and was developed

     based on the use of econometric techniques to estimate

    the frontier of production technology. Such models

    were initially developed by Farrell (1957) who also

    gave the definition of efficiency for firms. In this study,

    Farrell highlighted for the first time, the importance of

    assessing the so-called marginal production function(frontier production function). It is also called as the

    curve of isoproductivity of the most efficient firm

    which is the geometric field of points which reflect the

     perfect combination of productive factors among the

    sampled firms. Initially, Farrell attempted to measure

    the performance of a production unit, by applying a

    model of a single input and a single output [1]. He

    applied this model to assess the efficiency of American

    agriculture compared with other countries. He found out

    that aggregation of the various inputs and outputs to a

    single input and output, respectively, did not have the

    expected outcome. However, after years, his method

    was developed and can measure the performance ofoperating units with multiple inputs and outputs based

    on linear programming.

    Unlike econometric approaches, which attempt to

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    determine the ultimate effectiveness of a decision-

    making unit (DMU) compared with a benchmark set

    externally as a standard; non-parametric methods seek

    to evaluate the efficiency of a firm in relation with other

    firms in the same sector. This class of non-parametric

    models is referred as Envelope Data Analysis (DEA)and was developed by using techniques based on linear

     programming approaches to the production technology

    (Charnes, Cooper and Rhodes, 1978-1979, Banker,

    Charnes and Cooper, 1984) [2]. The DEA method does

    not require the setting of a specific functional

    relationship between inputs and outputs and the total production capacity is determined through a linear

     process of integration of the observed input-output

    combinations for each decision-making firm together

    with assumptions about the scale and availability

    inflows and outflows. Farell (1957) ignores the firm’s

    internal production process, assuming that this functionis complex and therefore impossible to assess the

    overall situation. His method is based only on the

    measurements of input and output, which in almost allcases are measurable. He expressed the efficiency of

     plants using the TFP index, defined as the ratio of total

    outputs to total inputs. In his work for the first time

    linear programming techniques are introduced in order

    to determine efficiency and to analyze it into individual

    compartments.

    Successors of Farell were Charnes, Cooper and

    Rhodes (1978), who founded the Data Envelopment

    Analysis (DEA), introducing a new efficiency valuation

    technique [13]. This technique is a non-parametric

    method based on linear programming models, which

    achieves to quantitatively estimate the maximum value

    of the relative efficiency of production units. The DEAmethod assumes the existence of a set of production

    units, the Decision Making Units (DMUs), which

    operate in a single, comparable and uniform frame and

    consume the same multiple inputs and produce the same

    multiple outputs. Both inputs and outputs are varied,

    usually measured in different measurement scales

    depending on the nature of the problem and the

    availability of data. The inputs are "goods" to be saved

    (thus smaller consumption levels are more desirable),

    and the outputs are the "goods" to maximize (hence

    larger production levels are more desirable). When

    there are several inputs and outputs comparisons of

    units become difficult because one unit is very likely totake precedence over other units in an input or output,

     but can simultaneously underperform other

    inputs/outputs.

    Compared with previous methods DEA offers the

    chance to manage multiple inputs and outputs withouthaving to put in advance weights in each

    inflow/outflow. To proceed to the assessment and

    calculations it is not needed to convert the data to a

    system of values, to make the summation of inputs /

    outputs and valuation. DEA uses ordinary linear

     programming methods for the determination andcomparison of similar sets for each system calculates. It

    uses similar units as reference system, presenting pricesfor an inefficient unit, which should be amended so that

    this unit is effective. Ii even identifies the size of the

    required amendments on the basis of the remaining

    reference set. Ky Naraini Che Ku Yusof et al. (2010)

    Malaysian companies are examined with DEA using as

    inputs the operating and financial expenses and other

    assets and as outflows the sales [15]. Reza Tehrani et al.

    (2012) apply DEA using as inputs the liabilities and

    assets and as outputs the performance ratios. Nordin HjMohamad and Fatimah Said (2012) use the operating

    expenses and sales, as well as performance ratios [3]

    [17]. Kambiz Shahroodi and Fatemeh Feraghnia (2013)

    investigate pharmaceutical firms with the use of ROA

    to select the proper variables [14].

    Banks are always in the center of research with DEA.Specifically, applications of DEA in banks Giokas, D.,

    (1990) and Necmi K., (2011) using the cash items, fixed

    assets and liabilities as inputs and cash flows, and

    liquidity and profitability ratios as outputs. Still, the

    man-hour and the operating expenses are used; the

    square meters of buildings owned by banks are alsoused as inputs while transactions per branch are

    considered as outputs [4-8]. Furthermore, liquidity can

     be used as the only output while capital adequacy,efficiency or cash items can be used as the only inputs.

    Joe, Z., (2000) uses employees, assets and funds as

    inputs and the market value of the firms and the

     performance ratios as outputs [9]. In the papers of

    Premachandra, I.M., et al. (2011) [5] [18] and

    Toshiyuki, S., and Mika, G., (2009) they use the same

    inputs and outputs for application to banks [10]. Jose

    Humberto Ablanedo and Rosas et al. (2010) evaluate

    the ports of Malaysia by using only outputs which are

    the liquidity ratios, inventory turnover ratio,

     profitability ratios and receivables turnover ratio [11].

    Emel, A.B., (2003) follows six steps to select the

    appropriate inputs/outputs: Selection of sample andobservations; determination of the main economic

    dimensions to consider. The main dimensions to be

    examined (liquidity, activity, economic structure,

     profitability, growth and investment activity); filtering

    of samples depending on the economic dimensions. The

     primary economic ratios are restricted to those

    expressing more basic economic dimensions. Because

    usually ratios are correlated to each other some of them

    are excluded as they are expressed by others; use

    expertise advices for choosing the most appropriate

    economic ratios from the initially selected; application

    of DEA using these ratios; verification of results with

    the application of other methods, such as regression[12].

    During the last decades, the literature on DEA

    methods is continuously growing. In his work, Gabriel

    Tavaresa presents a large number of works that

    implement the DEA method, adjusting them accordingto the applied method and the examined sector. The

    large number of published works on DEA points out

    that this method has a great research interest [16].

    The main aim of this paper is to study the efficiency

    of a set of IT firms with of DEA for the period 2006-

    2010. This sector was chosen for its vast presence in theGreek economy. The field of Information Technology

    and Telecommunications plays arguably one of themost important roles in terms of socio-economic

    development, both globally and nationally. The

    investigated period was chosen deliberately as it is five

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    years prior to the economic recession in Greece which

    started in late 2010.

    In the first section of this thesis efficiency was

    explained with the presentation of the mathematical

    expression of evaluating a firm. The types of efficiency

    and the methods used to measure and evaluate firms based on profitability were also presented with the

    analysis of DEA. Also the two key terms of DEA,

    inputs and outputs were explained. In the second

    section the literature review for DEA is presented with

    the two basic models of DEA, the BCC and CCR. The

    third section presents specific data on the IT sector and presents the sample of the investigated firms. The

    fourth section outlines the variables that will be used to

    model and presents the methodology to be followed.

    The model chosen in this work is an output oriented

    model with three outputs and one input. In the final

    section DEA method is applied and the results are presented, based on which the classification of firms

    into profitable and not profitable takes place. Last but

    not least a comparison of the effects of DEA to theresults of the financial analysis takes place in order to

    confirm the efficiency of the applied process.

    Using weights and given values for inputs and

    outputs, the DEA method calculates the maximum

    comparative profitability of each firm in relation to the

    other firms of the sample. Also the DEA output is a

    threshold that reflects the best combination of

    maximum output from the inputs of each module. For

    the inefficient firms (technical efficiency

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     Apostolos G. Christopoulos et al The evaluation of the efficiency of listed companies, using nonparametric methods: An empirical analysis

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    xin, yjn is i input and output of j n DMU

    e is infinitesimal positive number

    This mathematical problem, when solved, will give

    the values of the weights u and v, which will maximize

    the efficiency of m DMU. If the rate of return is equal

    to one, then the MA is efficient, and will be set on the boundary; otherwise it is relatively non-effective. Still,

    it gives the efficiency of a single Unit Decision. In order

    to get the rate of return also for other decision units it is

    needed to solve more mathematical problems like this

    one.

    2.2 Input minimizing model

    A comparable linear programming typology is

     possible to minimize the weighted sums of inputs,

    setting the weighted sum of outputs equal to the unit.

    This model seeks to minimize the proportion of the

    inputs of the evaluated m DMU, based on a weighted

    combination of inputs and outputs of other units that

    exceed the m DMU. When evaluable m DMU, is

    estimated as inefficient, the solution to the dual problem

     provides some DMUs (the reference group, the peer

    group, or the reference set) estimated as effective

    weights of m DMU.

    Moreover, the optimal solution of the model provides

    a virtual DMU on the frontier, resulting as a linear

    combination of all DMUs reference. The m DMU

    evaluated, should be transformed to this virtual DMU,

    to become effective. This is done by a reduction ofinputs or extension of output.

    III.  MATHEMATICAL FORMULATION OF THE

    DEA MODEL 

    With the DEA method the decision whether a unit

    (DMU) is inefficient is based on the creation of a

    complex unit. This composite unit is a linearcombination of inputs and outputs of other units. The

    assumption of linearity is equivalent to the assumption

    that if two alternative production processes have been

    observed in practice, then each output process is a linear

    combination of both (wherein each process participateswith a weight), is also feasible (Banker, Morey 1986).

    The aim (for the case of reduction of input) is to find

    the minimum level of resources required for a unit

    operating in a particular environment to produce aspecified level of outputs. Similarly, in the case of

    increased output, the aim is to find the maximum levelof output that can be produced by a unit operating in a

     particular environment, given a fixed level of inputs.

    The efficiency of any unit is calculated by forming the

    ratio of the sum of outputs, each of which is assigned

    with a weight, to the sum of the input, which are also

    assigned with weights. Note that these weights can vary

    and are dependent to the decision maker. The

    relationship which defines efficiency (Charnes et al,

    1978) is therefore:

    where,

    i: input (i = 1,2,……m)

     j : unit (j=1,2,………n)r : output (r= 1,2,…………...s)

    Xij : i input of j unit

    Υrj : r output of j unit

    s : the number of outputs

    m : the number of inputs

    n : the number of units

    The relative efficiency of a particular decision unit

    (DMU0) is resulting from the maximization of the

    above formula (1). This maximization will take place

    under the one limitation for each unit which has the

    following form (2):

      The efficiency ratio is less than or equal to 1.

    So, there will be s + m variables and an equal number

    of limitations, as there are units n.

    The mathematical formula of this method for assessingthe profitability of DMU0 is therefore summarized as

    follows (Charnes et al, 1978):

    Where, j = 1,…,n

    Ur ≥0, r = 1,…,s Ni ≥0, i = 1,…,m

    Where,

    i: the input (i = 1,2,……m)

     j : the unit (j=1,2,………n)

    r : the output (r= 1,2,…………...s)Xij : i input of j unit

    Υrj : r output of j unit

    s : the number of outputs

    m : the number of inputs

    n : the number of unitsThe DEA provides an estimate on how efficient each

    unit is, based on actual inputs used to produce the

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    corresponding amounts of costs, without having precise

    knowledge of the relationship between inputs and

    outputs. The Ur and Ni weights are calculated by DEA

    and the values to be assigned to each input and output

    in order to maximize the efficiency ratio of the unit are

    calculated. This means that the resulting solution is thetotal price of Ur and Ni giving the unit under review the

    maximum efficiency ratio, while the efficiency ratio of

    the specific values does not exceed 1 for this unit or for

    any other unit of the same set of units. Therefore, the

    optimal values of Ur and Ni differ for different units,

    since they are the solution of (2).

    When the evaluated unit is included in the

    limitations, we conclude that there is always a solution

    to (2), with the value range between 0 and 1. The unit

    therefore will be efficient only if the value is 1. If it gets

    a value less than 1, then there is a subset of the set of peer data in which the unit belongs, in relation to which

    this appears inefficient. To qualify a unit as inefficient,

    it should be no other combination of weights such thatthey satisfy the efficiency conditions. Any other choice

    of weights than the one that has made by DEA will

    further deteriorate the performance of the unit.

    For the solution of the problem of valuation units, the

    DEA approach is based on creating frontier efficient

    units, called effective limit. This is determined by a line

     passing through the points P2, P3, P4 and P5. The

    technical efficient units are point 1, and any other unit

    located on the line segments connecting the turning

     points between them.

    The term "technical efficiency" has the meaning ofthe failure to reduce the input, without reducing outputs

    (or vice versa, failure to increase output without

    increasing input). So one unit displays technical

    inefficiency in the observed behavior, if the resultsshow that some of the inputs or outputs can be

    improved without worsen another input or output

    (Charnes, Cooper and Thrall, 1986).

    In this sense a unit which is on the efficient frontier

    does not necessarily mean that it is efficient. For

    example, the unit P5 output (or any other unit that may

     be located on the segment P4P5) is equal to that of P4,

     but has higher input. Thus the P5 although situated onthe efficient frontier (that has an efficiency ratio 100%

    according to DEA), it is not efficient. These cases are

    examined by the DEA with control deviation of

    variables between inputs and outputs.

    3.1 Financial Ratios

    Activity ratios express the extent that a production

    unit utilizes its assets by converting them into cash;

    liquidity ratios determine the short-term economic

    ability of a firm to meet its short-term obligations,

    considering its current assets and its working capital;

    efficiency ratios examine the ability of the firm andtherefore needs to be examined and for possible

    correlation between sales, production and profits;

    capital structure ratios and sustainability examine the

    economic situation of a firm in the long run byanalyzing its capital structure; investment ratios interest

    offer information for investors to decide on their

    investment in equity securities of the firm; operating

    expenditure ratios provide information about the policy

    followed by a firm towards its running costs and its

    efficiency towards these costs.

    The next step is to decide which ratios will be used

    for the evaluation of firms by a ranking of these ratios

    into inputs and outputs. The ratios of activity, capital

    structure and profitability and operating costs can beused to form inputs in a production process, since they

    examine the capital activity of these firms, their costs

    and the use of their assets. On the other hand, liquidity

    ratios, profitability and investment ratios can be used to

    form outputs, since they show the financial position of

    the company to profitability, performance andinvestment activity.

    IV.  SELECTION OF THE SAMPLE OF IT AND

    TELECOMMUNICATIONS SECTOR  

    The Information Technology sector in Greece is

    among the most growing sectors in the last fifteen

    years. The gradual liberalization since 2000 and the

    increasing demand for telecommunications services had

    a positive impact on the development of the market.

    Communications have been one of the sectors that

    significantly enhance the economy and have a direct

    impact on socio-cultural level of the population. In this

    case, the development of communication networks both

    for fixed and mobile telephony has been very fast. The

    market for fixed and mobile services has broadened

    considerably in recent years, mainly after the fully

    liberalization of telecommunications on 1st of January2001. Of course the major part of the investments ininformation technology has been undertaken by the

    former state monopoly of Hellenic Telecommunications

    Organisation (HTO). From the above it is understood

    that this sector is very important for the national

    economy, which even in the recent years of the

    economic crisis in Greece has relatively good performance. The selected companies for our analysis

    are as possible homogenous with respect to the products

    and services they offer. An important criterion for

    selecting companies was to be present in the market for

    the entire period under investigation (2006- 2010), and

    to be possible to have access to their financialstatements.

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     Apostolos G. Christopoulos et al The evaluation of the efficiency of listed companies, using nonparametric methods: An empirical analysis

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    7 | International Journal of Computer Systems, ISSN-(2394-1065), Vol. 02, Issue, 01, January, 2015

    V. SAMPLE AND METHODOLOGY WITH THE USE OF

    RATIOS

    The selected firms are listed in the Athens Exchange

    in the sector of information technology: ALT; COCON;

    BYT; ILI; PROF; PCSYST; INTR; PLAIS; INF; MSL;

    The model that is implemented in our analysis uses

    only outputs. Following it will be explained how anoutput turned into input in order to avoid errors in the

    application of the method. Since our sample is

    relatively small, we will apply 4 ratios in order to

    receive secure results. The outputs selected:

    1. ROΑ = 100* (EBIT / total assets)

    2. Receivables Turnover Ratio = net sales / average

    account of receivables

    3. Days’ inventory on hand (average) = days in year /

    inventory turnover

    4. Current Ratio = (cash items + receivables +

    inventories) / short term liabilities

    In this paper we apply the DEA using an inputs and

    outputs method. We apply DEA on the 10 selected

    firms for five years (2006- 2010). Next we assess the

     progress of the firms during these five years. The stepswe follow are:

      selection and presentation of ratios

      testing correlation of ratios

      financial analysis of firms on the basis of

    selected ratios

      application of DEA

      comparing the results of DEA with the results

    of the financial analysis

      conclusions

    TABLE 1. R ATIOS FOR 4 OUTPUTS FOR THE 10 FIRMS FOR 5 YEARS 

    2006 2007 2008 2009 2010

    Χ1  Χ2  Χ3  Χ4  Χ1  Χ2  Χ3  Χ4  Χ1  Χ2  Χ3  Χ4  Χ1  Χ2  Χ3  Χ4  Χ1  Χ2  Χ3  Χ4 

    Ε1  1.36% 0.84 1.65 1.26 1.52% 0.91 1.52 2.94 1.59% 0.55 1.27 1.67 1.12% 0.32 1.42 2.78 1.41% 0.1 1.52 1.19

    Ε2  2.24% 0.26 1.47 2.1 2.70% 0.69 1.8 2.53 7.35% 0.44 1.53 2.11 3.21% 0.32 1.94 1.45 3.65% 0.46 1.24 1

    Ε3  7.67% 2.21 7.76 1.79 7.71% 2.53 5.89 1.71 6.68% 2.37 7.82 1.8 1.94% 1.92 6.61 1.69 6.41% 1.59 5.35 1

    Ε4  9.21% 1.76 10.01 2.43 8.85% 1.75 11.25 2.82 7.33% 2.17 8.62 3.41 6.97% 1.29 9.83 1.5 8.09% 1.45 11.46 1.46

    Ε5  6.72% 2.29 11.14 1.75 7.78% 1.77 15.05 1.51 4.58% 1.38 13.97 1.98 3.24% 1.05 11.65 1.33 1.51% 1.9 14.56 1.4

    Ε6  8.06% 1.38 5.15 1.92 4.78% 1.54 4.26 1.46 1.58% 1.34 5.96 1.71 4.88% 1.19 6.45 1.64 5.15% 0.74 2.54 1.54

    Ε7  1.02% 0.23 1.95 4.69 1.07% 0.22 1.26 2.23 1.80% 1.18 1.96 1 2.62% 0.17 1.89 2.57 1.96% 0.15 2.54 1.96

    Ε8  6.68% 9.46 6.29 1.48 6.86% 8.33 6.01 1.44 2.64% 9.75 5.76 1.19 3.14% 8.66 5.67 1.36 1.93% 8.89 6.33 1.55

    Ε9  4.32% 2.03 11.3 3.62 3.89% 1.82 9.65 1.73 4.04% 2.85 11.88 1.42 2.46% 2.31 10.79 2.03 1.92% 1.91 11.54 1.96

    10  3.88% 2.7 2.9 2.53 5.87% 3.48 0.91 3.89 6.38% 5.03 1.69 2.28 11.73% 3.66 1.4 1.92 7.48% 3.78 1.69 2.15

    Where,

    X1= return on asset

    Χ2 = receivables turnover ratio

    Χ3 = inventories turnover ratio in days

    Χ4 = current ratio

    Ε1= ALT

    E2=COCON

    E3=BYT

    E4=ILIE5=PROF

    E6=PCSYST

    E7=INTR

    E8=PLAIS

    E9=INF

    E10=MSL

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    TABLE 2. R ATIOS WITH 3 OUTPUTS AND 1 INPUT FOR THE 10 FIRMS FOR 5 YEARS 

    2006 2007 2008 2009 2010

    Χ1  Χ2  Χ3  Χ4  Χ1  Χ2  Χ3  Χ4  Χ1  Χ2  Χ3  Χ4 Χ1  Χ2  Χ3  Χ4  Χ1  Χ2  Χ3  Χ4 

    1  1.36% 0.84 221.21 1.26 1.52% 0.91 240.13 2.94 1.59% 0.55 287.4 1.67 1.12% 0.32 257.04 2.78 1.41% 0.1 240.13 1.19

    2  2.24% 0.26 248.3 2.1 2.70% 0.69 202.78 2.53 7.35% 0.44 238.56 2.11 3.21% 0.32 188.14 1.45 3.65% 0.46 294.35 1

    3  7.67% 2.21 47.04 1.79 7.71% 2.53 61.97 1.71 6.68% 2.37 46.68 1.8 1.94% 1.92 55.22 1.69 6.41% 1.59 68.22 1

    4  9.21% 1.76 36.46 2.43 8.85% 1.75 32.44 2.82 7.33% 2.17 42.34 3.41 6.97% 1.29 37.13 1.5 8.09% 1.45 31.85 1.46

    5  6.72% 2.29 32.76 1.75 7.78% 1.77 24.25 1.51 4.58% 1.38 26.13 1.98 3.24% 1.05 31.33 1.33 1.51% 1.9 25.07 1.4

    6  8.06% 1.38 70.87 1.92 4.78% 1.54 85.68 1.46 1.58% 1.34 61.24 1.71 4.88% 1.19 56.59 1.64 5.15% 0.74 143.7 1.54

    7  1.02% 0.23 187.18 4.69 1.07% 0.22 289.68 2.23 1.80% 1.18 186.22 1 2.62% 0.17 193.12 2.57 1.96% 0.15 143.7 1.96

    8  6.68% 9.46 58.03 1.48 6.86% 8.33 60.73 1.44 2.64% 9.75 63.37 1.19 3.14% 8.66 64.37 1.36 1.93% 8.89 57.66 1.55

    9  4.32% 2.03 32.3 3.62 3.89% 1.82 37.82 1.73 4.04% 2.85 30.72 1.42 2.46% 2.31 33.83 2.03 1.92% 1.91 31.63 1.96

    10  3.88% 2.7 125.86 2.53 5.87% 3.48 401.1 3.89 6.38% 5.03 215.98 2.28 11.73% 3.66 260.71 1.92 7.48% 3.78 215.98 2.15

    Where,

    X1= return on assetΧ2 = receivables turnover ratioΧ3 = inventories turnover ratio (in days)

    Χ4 = current ratio

    Ε1= ALT

    E2=COCON

    E3=BYT

    E4=ILIE5=PROFE6=PCSYST

    E7=INTR

    E8=PLAIS

    E9=INF

    E10=MSL

    TABLE 3. DESCRIPTIVE STATISTICS OF RATIOS FOR ALT

    Χ1  Χ2  Χ3  Χ4 

    Mean 1.410 0.470 256.170 2.145

    Standard Error 0.103 0.173 11.145 0.425

    Median 1.465 0.430 248.131 2.225

    Mode 240

    Standard Deviation 0.207 0.346 22.290 0.851

    Sample Variance 0.040 0.11 496.870 0.724

    Kyrtosis 1.500 -0.314 1.124 -4.320

    Skewness -1.293 0.509 1.335 -0.237

    Range 0.47 0.81 47.27 1.75

    Minimum 1.12 0.10 240.13 1.19

    Maximum 2 1 287 3

    TABLE 4. DESCRIPTIVE STATISTICS OF RATIOS FOR COCONΧ1  Χ2  Χ3  Χ4 

    Mean 4.227 0.48 230.959 1.772

    Standard Error 1.058 0.077 23.636 0.340

    Median 3.430 0.450 220.669 0.340

    Mode

    Standard Deviation 2.117 0.154 47.272 0.680

    Sample Variance 4.484 2.013 2234.700 -2.464

    Kyrtosis 3.358 2.013 -0.052 -2.464

    Skewness 1.799 1.016 0.974 1.530

    Range 4.65 0.37 106.21 1.00

    Minimum 2.70 0.32 188.14 1.00

    Maximum 7 1 294 3

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    TABLE 5. DESCRIPTIVE STATISTICS OF RATIOS FOR BYT

    Χ1  Χ2  Χ3  Χ4 

    Mean 5.720 2.102 58.022 1.752

    Standard Error 1.288 0.214 4.521 0.030

    Median 6.615 2.145 58.594 1.755

    Mode

    Standard Deviation 2.577 0.428 9.242 0.061

    Sample Variance 6.644 0.183 85.424 0.003

    Kyrtosis 3.224 -2.738 -0.840 -5.348

    Skewness -1.730 -0.368 -0.303 -0.068

    Range 5.77 0.94 21.55 0.12

    Minimum 1.94 1.59 46.68 1.69

    Maximum 8 3 68 2

    TABLE 6. DESCRIPTIVE STATISTICS OF RATIOS FOR ILI

    Χ1  Χ2  Χ3  Χ4 

    Mean 7.810 1.665 35.940 2.297

    Standard Error 0.417 0.193 2.438 0.487

    Median 7.710 1.600 34.787 2.160

    Mode

    Standard Deviation 0.835 0.386 4.877 0.974

    Sample Variance 0.698 0.149 23.790 0.949

    Kyrtosis -1.707 -0.559 -1.066 -4.243

    Skewness 0.506 0.768 0.876 0.306

    Range 1.88 0.88 10.49 1.95

    Minimum 6.97 1.29 31.85 1.46

    Maximum 9 2 42 3

    TABLE 7. DESCRIPTIVE STATISTICS OF RATIOS FOR PROF

    Χ1  Χ2  Χ3  Χ4 

    Mean 4.277 1.525 26.690 1.555

    Standard Error 1.325 0.193 1.598 0.146

    Median 3.910 1.575 25.598 1.455

    Mode

    Standard Deviation 2.651 0.386 3.184 0.292

    Sample Variance 7.031 0.149 10.140 0.085

    Kyrtosis 0.679 -2.295 2.854 2.708

    Skewness 0.739 -0.495 1.663 1.633

    Range 6.27 0.85 7.08 0.65

    Minimum 1.51 1.05 24.25 1.33

    Maximum 8 2 31 2

    TABLE 8. DESCRIPTIVE STATISTICS FOR RATIOS FOR PCSYST

    Χ1  Χ2  Χ3  Χ4 

    Mean 4.097 1.202 86.803 1.587

    Standard Error 0.842 0.170 20.010 0.050

    Median 4.830 1.265 73461.000 1.590

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    Mode

    Standard Deviation 1.685 0.340 40.020 0.109

    Sample Variance 2.841 0.12 1601.626 0.012

    Kyrtosis 3.837 1.232 1.756 -2.051

    Skewness -1.947 -0.981 1.455 -0.098

    Range 3.57 0.80 87.11 0.25

    Minimum 1.58 0.74 56.59 1.46

    Maximum 5 2 144 2

    TABLE 9. DESCRIPTIVE STATISTICS OF RATIOS FOR INTR

    Χ1  Χ2  Χ3  Χ4 

    Mean 1.860 0.430 203.182 1.940

    Standard Error 0.318 0.250 30.830 0.337

    Median 1.880 0.195 189.670 2.095

    Mode

    Standard Deviation 0.636 0.500 61.668 0.674

    Sample Variance 0.405 0.25 3803.040 0.455

    Kyrtosis 1.202 3.929 2.309 1.721

    Skewness -0.161 1.979 1.224 -1.208

    Range 1.55 1.03 145.98 1.57

    Minimum 1.07 0.15 143.70 1.00

    Maximum 3 1 290 3

    TABLE 10. DESCRIPTIVE STATISTICS OF RATIOS FOR PLAIS

    Χ1  Χ2  Χ3  Χ4 

    Mean 3.642 8.907 61.530 1.385

    Standard Error 1.100 0.303 1.501 0.075

    Median 2.890 8.775 62.050 1.400

    Mode

    Standard Deviation 2.201 0.606 3.003 1.151

    Sample Variance 4.847 0.37 9.021 0.022

    Kyrtosis 3.070 1.707 -1.149 0.381

    Skewness 1.696 1.164 -0.725 -0.530

    Range 4.93 1.42 6.71 0.36

    Minimum 1.93 8.33 57.66 1.19

    Maximum 7 10 64 2

    TABLE 11. DESCRIPTIVE STATISTICS OF RATIOS FOR INFO

    Χ1  Χ2  Χ3  Χ4 

    Mean 3.077 2.222 33.501 1.785

    Standard Error 0.525 0.234 1.581 0.137

    Median 3.175 2.110 32.728 1.845

    Mode

    Standard Deviation 1.050 1.469 3.162 0.275

    Sample Variance 1.102 0.22 10.003 0.075

    Kyrtosis -4.630 -0.396 0.522 -0.506

    Skewness -0.200 0.979 1.113 -0.920

    Range 2.12 1.03 7.10 0.61

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    Minimum 1.92 1.82 30.72 1.42

    Maximum 4 3 38 2

    TABLE 12. DESCRIPTIVE STATISTICS OF RATIOS FOR MSL

    Χ1  Χ2  Χ3  Χ4 

    Mean 7.865 3.987 273.441 2.560

    Standard Error 1.331 0.352 43.839 0.449

    Median 6.930 3.720 215.976 2.215

    Mode

    Standard Deviation 2.662 0.705 87.68 0.899

    Sample Variance 7.090 0.5 7687.628 0.808

    Kyrtosis 2.669 3.431 2.710 3.494

    Skewness 1.640 1.816 1.680 1.834

    Range 5.86 1.55 185.12 1.97

    Minimum 5.87 3.48 245.98 1.92

    Maximum 12 5 401 4

    TABLE 13. AVERAGES OF RATIOS FOR EACH FIRM FOR THE PERIOD 2006-2010

    Χ1  Χ2  Χ3  Χ4 

    Ε1  1.4% 0.54 248.3 1.96

    Ε2  3.83% 0.43 229.56 1.83

    Ε3  6.11% 2.12 53.21 1.76

    Ε4  8.09% 1.68 35.68 2.32

    Ε5  4.76% 1.67 27.51 1.59

    Ε6  4.89% 1.23 74.95 1.65

    Ε7  1.69% 0.39 190.1 2.49

    Ε8  4.21% 9.01 60.73 1.4

    Ε9  3.32% 2.18 33.09 2.15

    Ε10  7.06% 3.73 213.45 2.55

    Where,

    X1= return on asset

    Χ2 = receivables turnover ratioΧ3 = inventories turnover ratio in days

    Χ4 = current ratio

    Ε1= ALT

    E2=COCON

    E3=BYT

    E4=ILI

    E5=PROF

    E6=PCSYST

    E7=INTRE8=PLAIS

    E9=INFE10=MSL

    TABLE 14. R ATIO AVERAGE PER YEAR  

    Χ1  Χ2  Χ3  Χ4 

    2006 5.09% 2.31 61.24 2.35

    2007 5.10% 2.3 63.37 2.22

    2008 4.41% 2.7 60.43 1.85

    2009 4.13% 2.08 63.37 1.822010 3.95% 2.09 62.18 1.6

    Average 4.54% 2.3 62.12 1.97

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    Where,

    X1= return on asset

    Χ2 = receivables turnover ratio

    Χ3 = inventories turnover ratio in days

    Χ4 = current ratio

    In our analysis we make an assumption concerning

    the ratios’ prices when they are either zero or negative.

    In order to properly use these ratios, we took accepted

    these prices as positive, under the limitation that they

    are smaller compared to the relevant prices of the other

    firms for the particular year. This assumption ensuresthat we will have measurable values for all ratios and

    that the transformed values will not lead to wrong

    conclusions.

    VI.  R ATIOS’ CORRELATION

    In order to come to a final decision for the selectedratios we applied correlation tests for every one of

    them. Specifically, we examined for each firm the

    existence of correlation for ratios by testing these ratios

     pairwise with the Spearman correlation coefficient

    which is a non-parametric measure of statisticaldependence between two variables and is denoted by p.

    The Spearman ratio evaluates how well the relationship

     between two variables is described using a monotonic

    function. If there are no repeated data values, a perfect

    Spearman correlation by +1 or -1 is the case where each

    of the variables is a perfectly monotonic function of the

    other. The Spearman correlation coefficient is defined

    as the Pearson correlation coefficient between the rating

    variables. The n scores Xi, Yi converted into rankings

    xi, yi, and p is calculated by the formula:

    Where,

      If p = ±1 there is perfect linear correlation.

      If−0,3≤ p < 0,3 there is no perfect linear

    correlation.

      If −0,5 < p ≤ −0,3 ή 0,3≤ r < 0,5 there is weak

    linear correlation.  If −0,7 < p ≤ −0,5 ή 0,5 ≤ r < 0,7 there is

    average linear correlation.

      If −0,8 < p ≤ −0,7 ή 0,7 ≤ r < 0,8 there is a

    strong linear correlation.

      If −1< p ≤ −0,8 ή 0,8 ≤ p

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    TABLE 18. R ATIOS CORRELATION OF ILI

    Χ1  Χ2  Χ3  Χ4 

    Χ1  1

    Χ2  0.06 1

    Χ3  0.36 0.2 1

    Χ4  0.1 0.36 0.25 1

    TABLE 19. R ATIOS CORRELATION OF PROF

    Χ1  Χ2  Χ3  Χ4 

    Χ1  1

    Χ2  0.36 1

    Χ3  0.03 0.01 1

    Χ4  0.37 0.18 0.01 1

    TABLE 20. R ATIOS CORRELATION OF PCSYST

    Χ1  Χ2  Χ3  Χ4 

    Χ1  1

    Χ2  0.01 1

    Χ3  0.23 0.55 1

    Χ4  0.4 0.19 0.45 1

    TABLE 21. R ATIOS CORRELATION OF INTR

    Χ1  Χ2  Χ3  Χ4 

    Χ1  1

    Χ2  0.02 1

    Χ3  0.43 0.03 1

    Χ4  0.42 0.06 0.06 1

    TABLE 22. R ATIOS CORRELATION OF PLAIS

    Χ1  Χ2  Χ3  Χ4 

    Χ1  1

    Χ2  0.24 1

    Χ3  0.24 0.03 1

    Χ4  0.31 0.09 0.2 1

    TABLE 23. R ATIOS CORRELATION OF INFO

    Χ1  Χ2  Χ3  Χ4 

    Χ1  1

    Χ2  0.22 1

    Χ3  0.11 0.59 1

    Χ4  0.29 0.36 0.09 1

    TABLE 24. R ATIOS CORRELATION OF MSL

    Χ1  Χ2  Χ3  Χ4 

    Χ1  1

    Χ2  0.24 1

    Χ3  0.49 0.27 1

    Χ4  0.49 0.24 0.38 1

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    Where,

    X1= return on asset

    Χ2 = receivables turnover ratio

    Χ3 = inventories turnover ratio in days

    Χ4 = current ratio

    From the above tables which are in line with the

    ratios’ theory of when two variables are correlated and

    what kind of relationship they have with each other, wecan conclude that the selected ratios have low

    correlation between them. The values of p range from

    0.01 up to 0.56. Therefore, we can go to our

    calculations, using their values. The financial analysis

    of the examined firms based on the selected ratios is

     presented in the following section.

    VII. 

    FINANCIAL ANALYSIS OF FIRMS BASED ONTHE SELECTED RATIOS

    In this section we can see the performance of the ten

    selected firms by using the four ratios, following with

    the conclusions for the examined firms. In our analysiswe examine every firm for each ratio for the period of

    five years (2006-2010). Initially, firms are examined for

    each year, and then they are compared based on the

    average rate of the ten firms for the particular year,

    which is considered as the average rate of the sector.

    Then we find the overall averages of firms for the entire

     period of the five years.

    According to the first ratio, which is the asset

    efficiency, we test the ten firms for their efficiency. As

    already mentioned, the efficiency of a company is its

    ability to generate profits. It shows how efficient is the

    firm’s management to utilize its assets in an appropriate

    manner to produce revenues. The higher the index, the

     better is for the firm which can go on and to attract new

    capitals for investment.

    The firm with the highest profit for 2006 was ILI

    with ratio 9.21%, much higher than the industry

    average, which is 5.09%. The lower profit ratio was for

    INTRA, at 1.02%. For 2007 ILI holds the primacy in

    the industry, with 8.85%, while INTRA notes a slight

    increase in profits with a ratio of 1.07%, but stillremains last in the sector (sector is relatively steady at

    5.1%). In 2008 COCON manages to be first with

    7.35%, while ALT notes the smaller profits in the

    sector, with 1.59%, but at the same time the sector to

    fall to 4.41%. In 2009 the presence of MSL is dynamic,with a ratio 11.73%, much higher than the 4.13% of the

    sector, while the last in the sector is still ALT with a

    ratio of 1.12%. In 2010, the higher profits are again for

    ILI with a ratio of 8.09%, and the lower profits are for

    ALT by 1.41%, while the average of the sector are

    further reduced to 3.95%.

    Then, we calculated the averages of ratios for each

    firm for the five years period. Overall in these five years

    we see that ILI manages the have the largest profit, with

    an average for the five years at 8.09%, followed by

    MSL with 7.06%. Last on the scale is ALT with 1.4%.

    The receivables turnover ratio shows how many

    times on average a firm collects its receivables duringthe accounting year. It is therefore desirable to have a

    higher ratio which means that the firm’s sales are higher

    than its receivables.

    For 2006, PLAIS is the firm that manages to collect

    the receivables better than the rest of the sector, with a

    ratio 9.46, compared to the sector’s average 2.31, while

    the lowest percentage of receivables are collected by

    INTRA, with a ratio of 0.23. In 2007 PLAIS is again

    first with a downward trend at 8.33, while INTRA

    continues steadily to 0.22, and the average of the

    examined firms in the sector to be 2.3. In 2008 PLAIS

    notes a further increase with a ratio of 9.75, whileCOCON show a decrease in its ability to collect

    receivables with a ratio 0.44 while at the same time theaverage for the ten firms is 2.7. In 2009 PLAIS remains

    on the top although with a decrease to 8.66, and INTRA

    is last with a ratio 0.17, while the industry is on average

    2.08. The best performance to collect receivables is

    therefore PLAIS for the five years period from 2006 to

    2010 with an average ratio of 8.89, while ALT is lastwith a ratio 0.1 and the sector’s average to be at a ratio

    of 2.09. For the total period of investigation the average

    receivables turnover ratio is greater for the firm PLAIS

    (9.01), while the lower ratio is for COCON (0.43)

    The use of inventories turnover ratio offers

    significant findings relevant to the ability of a firm to

    manage its inventories efficiently.

    For 2006 the firm which managed to sell inventories

    in hand in the best way was INFO, with a ratio of 11.3

    and an average number of 32.3 days to sell inventories

    in hand, while on the other hand inventories of COCON

    had an average 248.3 days for this year and a ratio of

    inventories turnover ratio at 1.47, while for the sector

    the average ratio of inventories turnover ratio was 5.96

    and the period of inventories in hand to sell was 61.24

    days. For 2007, PROF’s average number of days takento sell its inventories on hand was better than the other

    firms, with an average ratio of 24.25 days and a ratio of

    inventories turnover ratio at 15.05, much lower than the

    sector’s average of 63.37 days and inventories turnoverratio 5.76). At the same time MSL does not do so well,

    with an average time to replace its inventories of 401.1

    days and ratio of inventories turnover ratio. 0.91. In

    2008 PROF holds the lead with an average time to

    replace its inventories of 26.13 days and ratio

    inventories turnover ratio 13.97 (compared to 60.43days and inventories turnover ratio 6.04 of the sector).

    The worse average number of days taken to sell

    inventories on hand for 2008 is ALT with a ratio of

    inventories turnover ratio 1.27 and an average of 287.4

    days. In 2009 PROF notes a decrease, but still remains

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    high compared to the sector average, with an average

    time of 31.33 days and a ratio of inventories turnover

    ratio 11.65, while the sector is at 63.37 days and a.

    Social Insurance Fund 5.76 and last is the MSL, with an

    average residence time of the stock 260.71 days and

    inventories turnover ratio is 5.76 and at the end is MSLwith an average of 260.71 days and inventories turnover

    ratio 1.4. In 2010 PROF closes the five years period

    with an average time to replace its inventories 25.07

    days and inventories turnover ratio 14.56, while

    COCON notes a lower ratio with an average time to

    replace its inventories 294.35 days and inventoriesturnover ratio 1.24. The sector’s average in the

    respective year is 62.18 days and inventories turnover

    ratio 5.88. In 2010 PROF closes five years with an

    average time to replace its inventories 25.07 days and

    inventories turnover ratio 14.56, while COCON has a

    lower ratio with an average time to replace itsinventories 294.35 days and inventories turnover ratio

    1.24. At the same year the sector’s average is 62.18

    days and the ratio inventories turnover ratio 5.88.

    From the averages of the time to replace its

    inventories for each firm for the entire period of the fiveyears, we found that the lower average time to replace

    its inventories is for PROF, with 27.51 days and a ratio

    of inventories turnover ratio 13.27, followed by INFO,

    with 33.09 days and inventories turnover ratio 11.03.

    The highest average ratio for the entire period of five

    years is for ALT, with 248.3 days and a ratio ofinventories turnover ratio 1.47, followed by COCON,

    with 229.56 days and inventories turnover ratio 1.59.

    The current ratio defines the financial position of afirm in the short run and therefore its ability to meet its

    short-term liabilities. Specifically, we can see howmany times a firm covers its current liabilities by its

    current assets. The higher this ratio is the better in terms

    of liquidity is the position of this firm.

    Better liquidity for 2006 presented by INTRA, with a

    ratio of 4.69 and the lower for ALT, with a ratio of

    1.26, while the average for all firms is 2.35. The 2007

    MSL displays liquidity 3.89, higher than the 2.22

    average of the sector, while PLAIS has a liquidity ratio

    of 1.44. In 2008 ILI notes the highest of 3.41 and

    INTRA the lowest ratio of 1.0, while the sector shows a

    decrease in liquidity with 1.82. In 2010, the five years

     period ends with ALT showing the highest liquidity

    ratio between the ten examined firms, with a ratio of

    2.78 and COCON the lowest one with a ratio of 1.0while the sector’s average is at 1.6.

    From the averages of the current ratios for the ten

    firms for the entire five years period, we can see that the

    highest liquidity on average for the five years is for the

    company MSL, with a ratio of 2.55, followed byINTRA, with 2.49. The lower average ratio for the five

    years is for PLAIS with 1.4, followed by PROF, with

    1.59.

    A remarkable conclusion, based on the averages of

    the four ratios for all ten firms per year, is thedownward trend which is noted in all four ratios over

    the examined years. The sector seems to fall in profits,

    starting from an average return on assets at 5.09% in2006 and ending at 3.95% in 2010. It also seems that

    the average receivables turnover ratio was reduced from

    2.31 in 2006 to 2.09 in 2010. Downward is also the

    average inventories turnover ratio, which starts from

    5.96% in 2006 and ends at 5.87% in 2010. The average

    time to replace its inventories has increased over the

    years, from 61.24 days in 2006 to 62.18 days in 2010.

    Last but not least, the liquidity of the examined firms

    of the sector is also declining, with the ratio to start in

    2006 from 2.35 and to reach 1.6 in 2010. This

    downward trend in the examined ratios for the sector

    which are related with the outputs of our model showsthe overall downward trend in the sector of Information

    Technology for the years 2006 to 2010, when the crisis

     period started in Greece.

    VIII.  APPLICATION OF DEA

    To implement the DEA method, we applied the

     program DeaOS and the results from this application for

    the ten examined firms for the five years ofinvestigation (2006-2010) are presented in Table 25.

    TABLE 25. CORPORATE PERFORMANCE RESULTS FOR 2006-2010

    2006 2007 2008 2009 2010 Average

    Ε1  0.05 0.14 0.07 0.18 0.08 0.1

    Ε2  0.07 0.14 0.18 0.15 0.07 0.12

    Ε3  0.7 0.47 0.87 0.51 0.41 0.59

    Ε4  1 1 1 1 1 1

    Ε5  0.93 1 1 0.83 1 0.95

    Ε6  0.45 0.24 0.37 0.6 0.2 0.37

    Ε7  0.22 0.9 0.08 0.22 0.22 0.33

    Ε8  1 1 1 1 1 1

    Ε9  1 0.64 1 1 1 0.93

    Ε10  0.23 0.12 0.24 0.27 0.23 0.22

    Average 0.57 0.57 0.58 0.58 0.52 0.56

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    Where,

    Ε1= ALT

    E2=COCON

    E3=BYT

    E4=ILI

    E5=PROF

    E6=PCSYST

    E7=INTR

    E8=PLAIS

    E9=INF

    E10=MSL

    TABLE 26. DESCRIPTIVE STATISTICS FOR PERFORMANCE 

    2006 2007 2008 2009 2010

    Mean 0.622 0.565 0.581 0.576 0.521

    Standard Error 0.127 0.122 0.134 0.113 0.133

    Median 0.700 0.555 0.620 0.555 0.320

    Mode 1 1 1 1 1

    Standard Deviation 0.383 0.388 0.424 0.360 0.422

    Sample Variance 0.147 0.151 0.179 0.129 0.178

    Kyrtosis -1.935 -2.084 -2.298 -1.959 -2.174

    Skewness -0.305 0.019 -0.098 0.093 0.323

    Range 0.93 0.88 0.93 0.85 0.93

    Minimum 0.07 0.12 0.07 0.15 0.07

    Maximum 1 1 1 1 1

    IX.  GENERAL CONCLUSION 

    From Table 20 with the efficiency scores for the ten

    firms for the five years period, we can draw conclusions

    from the implementation of the method. Resulting

    conclusions on which firms managed to qualify as

    efficient (efficiency is equal to 1), and which firms werenon-profitable firms. We can draw conclusions aboutwhich firms are close to be characterized as efficient

    and which are very low in efficiency in relation to the

    other firms of the sector. Conclusions can be made

    comparing all the firms for each year, but also for each

    company within the period of the five years (2006-

    2010).

    8.1 Conclusions for the per year effiiciency of firms

    Specifically, for 2006 only three firms (E4, E8, E9)

    are efficient, i.e. only the 30% of the sample, while the

    average efficiency for this year is 0.57. From the non-

    efficient firms, E1 (0.05), has the lower efficiency whileat the same levels we find also E2, E3. Very close to be

    characterized as efficient is firm E5 while moderate

    efficiency is presented for E6.

    For the year 2007, efficient are three firms (E4, E5,

    E8), i.e. 30% of the sample while E7 (0.9) is very close

    to efficiency (close to 1). The average efficiency for theyear is 0.57. From the inefficient firms, E10 (0.12), E1

    (0.14) and E2 (0.14) show low efficiency.

    In 2008 four firms manage to have efficiency equal to

    1 (E4, E5, E8, E9) so 40% of the sample is efficient

    while the average for 2008 is equal to 0.58. The lower

    efficiency is for the firms E1 and E7, while relatively

    high (close to 1) is the efficiency of E3 (0.87).In 2009 the efficient firms are again three (E4, E8,

    E9), so 30% of the sample is efficient, while the

    average for this year is 0.58. From the inefficient firms

    E2 (0.15) has the lower efficiency followed by E1

    (0.18), while E5 is approaching to become efficient

    with 0.83.In 2010 efficiency firms are four (E4, E5, E8, E9),

    which represents the 40% of the sample, while the

    average efficiency is equal to 0.52. From the inefficient

    firms, E6 (0.02) shows the lower efficiency, followed

     by E2 (0.07) and E1 (0.08).

    8.2 Conclusions for each firm for the five years period

    The firms E4 and E8 are efficient for the entire

     period of the five years. As far as the other five firms,

    the best efficiency score is achieved by the firm E5,

    with an average of 0.95 in five years, followed by the

    firm E9 with an efficiency score of 0.93. The firm E3

    has a relatively low efficiency score (0.59), while E6

    and E7 are following with even lower efficiency scores

    (0.37 and 0.33 respectively) and in the last position we

    find the firm E10 with a score of 0.22, the firm E2 witha score of 0.12 and the firm E1 with a score of 0.1.

    The firm E1 has very low efficiency scores in the

     period of the five years, ranging from 0.05 up to 0.18,

     presenting the lowest efficiency scores in all the years

    compared to the other firms of the sample. The firm E2

    is moving in the same context with the E1, with an

    average of five years slightly higher than E2, (0.12

    compared to the 0.1 of E1). The firm E3 presents high

    variation in the rates of return for the period of the five

    years, with values ranging from 0.07 in 2006 to 0.87 in

    2008. The average rate of efficiency for the firm E3 is

    0.59, which means that it cannot be characterized as

     particularly efficient during this five years period.The firms E4 and E8 are efficient for the entire

     period of the five years according to the DEA method.

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    The firm E5 is efficient for the three of the five

    examined years, while for two years it is not efficient

    although its scores are quite high (0.93 and 0.83). The

    firm E6 has relatively low efficiency in the five years,

    with an average of 0.37. Its higher efficiency score 0.6

    is in 2009 and its lower efficiency score 0.2 is in theyear 2010, while the firm E7 is also equally inefficient

    to E6. The average of the firm E6 for the examined

     period is 0.33 with its higher score of efficiency to be in

    the year 2007 (0.9) and lower efficiency score in 2008

    (0.08). The firm E9 is almost in the same level with the

    firm E5, being efficient for four of the five years of theinvestigated period, while for one year it is inefficient,

    with a score of efficiency 0.64 and an average

    efficiency score for the five years 0.93. Finally, the firm

    E10 has a low efficiency scores, with an average of 0.22

    for the five years period with its highest efficiency score

    to be in the year 2009 (0.27) and its lowest in 2007(0.12).

    X. 

    COMPARISON OF DEA RESULTS WITH FINANCIAL

    ANALYSIS 

    Comparing the efficiency scores of DEA for the

    firms with the results of the financial analysis of thesame firms several interesting conclusions are

    generated.

    Starting from the two firms E4 and E8 which are

    characterized as efficient for the entire period of the five

    years, we see that for E4 efficiency is established also

     by the DEA method, since E4 has managed the highest profits for the five years and has on average the highest

    asset efficiency. On the other hand, firm E8 notes the

    highest average of turnover receivables ratio but at thesame time it is the firm with the lower liquidity

    compared to the other firms for the period of the five

    years. Therefore, we can see that at a high percentage,the results of DEA are in line with the results of the

    financial analysis for both firms E4 and E8.

    Continuing with the examination of the inefficient

    firms, E9 shows quite low average turnover inventories

    ratio which means that it manages to sell inventories on

    hand in less days and also has quite good liquidity

     performance. Also the firm E5 has the greatest turnover

    inventories ratio with the highest average rate among

    the firms of the examined sample. However, E5

     presents a low current ratio for the period of five yearswhich allows us to conclude again that DEA method is

    at a high percent in line with the results of the financial

    analysis for the examined firms.

    The firm E3 has an average efficiency ratio 0.59 for

    the five years, which places it in a fair condition of the

    efficiency scale. This is confirmed also by its financial

    situation, since in the average ratios for the period of the

    five years the efficiency score is close to the overall

    averages of the sector. In particular, the profitability of

    its assets is 6.11 slightly higher than the sector’s

    average (for five years is 4.53, Tables 13 and 14) the

    receivables turnover ratio is 2.12, slightly lower than

    the average of the sector, which is 2.3 while the currentasset ratio for E3 is averaged again near the average of

    the sector, i.e. 1.76 compared to 1.97. Finally, the

    average inventories turnover ratio is lower than the

    sector’s average which is 53 days compared with 62

    days respectively. In this case we can conclude that

    financial analysis for E3 is in line with the result of the

    DEA.

    As far as the firms E6 and E7 are concerned, they are

    the firms with the lower efficiency, followed by E10which is close to them. More specifically efficiency for

    E6 is on average equal to 0.37 while according to the

    financial analysis the receivables turnover ratio is half

    (1.23) compared to the sector’s average (2.3), and the

    days taken to sell inventories on hand is on average 74

    days for the five years period, much longer than theaverage of the sector (62 days). Also with the DEA

    method firm E7 is ranked as inefficient, with an

    efficiency ratio of 0.33. From the financial analysis we

    can see that the return on asset efficiency is 1.69 on

    average for the five years, compared to the sector’s

    average 4.5, while its receivables turnover ratio is alsolow (0.39). Nevertheless, the current ratio average is

     just above the sector’s average (2.49), but its number of

    days to sell inventories on hand is very high (190 days).The firm E10 is also low in terms of efficiency (0.22).

    In more detail, the return on assets, the receivables

    turnover ratio and the current ratio are lower than the

    sector’s averages, while the average number of days to

    sell inventories on hand is also lower. Therefore, the

    results of DEA are in line with the results of the

    financial analysis for the two of the three examined

    firms.

    Finally, the firms with the lowest efficiency are E1

    and E2. The firm E1 has the lowest efficiency score of

    0.1, while E2 is inefficient with efficiency score equal

    to 0.12. The firm E1 according to the financial analysis

    has the lowest profits in the period of five years, thelowest return on assets ratio, and relatively low

    receivables turnover ratio. On the other hand, E2 shows

    very low ratio for the five years both in terms of asset

    efficiency and for the average number of days taken to

    sell inventories on hand and also lower current ratio

    compared to the other firms. Therefore, also in this case

    of the DEA method the results are in line with the

    results of the financial analysis.

    In conclusion, we can say that for nine of the ten

    firms the results of DEA are in line with the conclusions

    resulting from the financial analysis for the sample of

    firms. Therefore, we can say with certainty that the

    evaluation of the ten firms of the informationtechnology sector is satisfactory and to draw reliable

    conclusions about their efficiency.

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