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Definition of Terms

A tabulation of data showing the number of times a

score appears.

The number of times a score or a group of scores

(class) occurs in a population or sample.

A group of scores in a population or sample.

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Definition of Terms

Halfway between the upper limit and lower limit of

a class (also called midpoint).

Halfway between the lower limit of one class and

the upper limit of the preceding class (the exact

limit).

The frequency of one score or group of scores

divided by the total frequency of all the

observations.

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Definition of Terms

The frequency of any class plus the frequencies of

all preceding class in a distribution.

A pictorial representation of a set of data.

A vertical bar graph that shows the frequencies of

scores or classes of scores by the height of the bar.

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Definition of Terms

A graph on which the frequencies of classes are

plotted at the class mark and the class marks are

connected by straight lines.

The relationship between two variables is shown by

a series of dots plotted on a graph.

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Formulas:

Where:

f = frequency

M = score or class mark

N = number of observations in the sample

A = assumed mean

=

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Formulas:

Difference between highest and lowest score.

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Formulas:

.

Square root of variance ()

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Formulas:

Values that divide a set of observations into 100

equal parts. It is denoted by P1 , P2,., P99, such that 1% of

the data falls below P1.

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Formulas:

Values that divide a set of observations into 10 equal

parts. It is denoted by D10 , D20,., D90, such that 20% of the

data falls below D20.

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Formulas:

Values that divide a set of observations into 4 equal

parts. It is denoted by Q1, Q2, ,Q3, such that 25% of the

data falls below Q1.

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Formulas: