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Customer Problems Metric

It is a type ofproduct quality metric that measures

the problems customer encounter when using the

products.

There are two types of customers problem is there.

1) Non-defect oriented problem.

2) Defect problem.

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Non-defects-oriented problems:

1) Not the valid defects.

2) May be the usability problems ( Uncleardocumentation or information).

3) Duplicates of valid defects( defects that

where reported by other customers and fixes where

available but the current customer did not know ofthem.)

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Defect problems:

Problems with the software defects.

Therefore the customer problem metric is usually

expressed in terms of problems per user

month(PUM).

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PUM = Totalproblemsthatcustomersreported(valid

defectsandnon-defect-orientedproblems)foratime

period Totalnumberoflicense-monthsofthe

softwareduringtheperiod.Example:

For 1 month number of license copy is 1000

Therefore for a certain period (Say 12 month)there willbe 12*1000=12000 license copy of the product.

So, PUM= Total Problem/12000.

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How to minimized Problem per user

month (PUM) metric ?

Improve the development process and reduce the

product defects.

Reduce the non-defects-oriented problems by

improving all aspects of the products (Such as

usability, documentation), customer education and

support.

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Difference between Defect rate and

Customer Problem metric.

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Customer Satisfaction Metrics

Often measured by customer survey data via five

point scale:

Very satisfied

Satisfied

Neutral

Dissatisfied

Very dissatisfied

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Basedonthesefivepointscaledataseveralmetrics

canbeconstructed.

Percentageofcompletelysatisfiedcustomer.

percentageofsatisfiedcustomer.

Percentofdissatisfiedcustomers.

Percentofnonsatisfied(neutral,dissatisfied,and

completelydissatisfied)

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Forthesemetrics weightingindexapproachcanbe

use(Knownasnetsatisfactionindex)

Completelysatisfied = 100%

Satisfied = 75%

Neutral = 50%

Dissatisfied = 25%

Completelydissatisfied = 0%

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In-Process Quality Metrics

In-Process quality metrics usedtomeasureproduct

duringdevelopmentprocess.

Inthismetricswewilldiscussthefollowing.

1. Defectarrivalpatternduringmachinetesting.

2. Phasebaseddefectremovalpattern.

3. Defectremovaleffectiveness.

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Defect arrival pattern during

machine testing

To measure defect arrival pattern, we have to

consider three different metrics.

The defect arrivals (defects reported) during the

testing phase by time interval (e.g., week). These arethe total arrival defects, not all of which are valid

defects.

The pattern of valid defect arrivals.

Thepatternofdefectbacklog(Processallthedefects

attheendofthedevelopmentcycle. Generally

retesting(regression test)isneededto ensurethat

targetedproduct qualitylevelsarereached.

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Phase based defect removal pattern

It requires the tracking of defects at all phases of the

development cycle, including the design reviews,

code inspections, and formal verifications beforetesting.

The pattern of phase-based defect removal reflects the

overall defect removal ability of the development

process.

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Project A

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Project B

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Defect Removal effectiveness

Defect removal effectiveness (or efficiency) can be

defined as follows:

DRE= (Defects removed during a developing process)/(Total defects in the product) *100.

The denominator of the metric can only be approximated. It

is usually estimated by:

Defects removed during the phase + defects found

later

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The higher the value of the metric, the more effective

the development process and the fewer the defects

escape to the next phase or to the field.

Based on this metric, action plans to improve the

effectiveness of these phases were established and

deployed.

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Phase effectiveness of a software project