PSYC4410 CH. 3

Identify a true statement about a frequency distribution.

All scores are listed alongside the number of times each score occurred.

_____ scales contain equal intervals between numbers.

Interval

Identify a true statement about a normal curve.

It approaches the X-axis asymptotically.

Identify the true statements about meta-analysis.

It can be replicated. It focuses more on effect size rather than statistical significance alone.

In the context of techniques to measure correlation, identify the true statements about the Pearson correlation coefficient

It can be used when the relationship between two variables is linear. It is the most widely used of all techniques devised to measure correlation.

Identify a true statement about skewness.

It is an indication of how the measurements in a distribution are distributed.

Identify a true statement about a rank-difference correlation coefficient.

It is frequently used when the sample size is small.

Identify a true statement about the coefficient of correlation.

It is interpreted by its sign and magnitude.

Identify an accurate statement about raw scores.

Raw scores can be converted into other types of scores.

The scale used in the computation of _____ can be called a fifty plus or minus ten scale.

T scores

Identify an accurate statement about measurement.

The rules used in assigning numbers are guidelines for representing the magnitude of an object being measured.

Identify an accurate statement about interval scales.

They contain no absolute zero point.

Which of the following statements is true of ordinal scales?

They imply nothing about how much greater one ranking is than another.

Identify the true statements about ordinal scales.

They permit classification. They permit rank ordering.

Identify true statements about scatterplots.

They provide a quick indication of the direction and magnitude of the relationship between two variables. They are useful in revealing the presence of curvilinearity in a relationship.

True or false: In special instances, such as when there are only a few scores and one or two of the scores are extreme in relation to the remaining ones, a measure of central tendency other than the mean may be desirable.

True

True or false: Standard scores are more easily interpretable than raw scores.

True

True or false: True or false: Nominal scales are the simplest form of measurement.

True

An expression of the degree and direction of correspondence between two things is known as _____.

correlation

A set of test scores arrayed for recording or study is known as a _____.

distribution

A feature of a normal curve is that it

has two tails

distributions that have high kurtosis

have a high peak and fatter tails

distributions that have low kurtosis

have a rounded peak and thinner tails

In the context of measurement, a feature of nominal scales is that they _____.

involve classification based on one or more distinguishing characteristics

A feature of a stanine is that it _____.

is divided into nine units

The term testing professionals use to refer to the steepness of a distribution in its center is

kurtosis

A statistic that indicates the average or midmost score between the extreme scores in a distribution is known as a _____.

measure of central tendency

The act of assigning numbers or symbols to characteristics of things according to rules is known as _____.

measurement

Statistics that describe the amount of variation in a distribution are referred to as _____.

measures of variability

A family of techniques used to statistically combine information across studies to produce single estimates of the data under study may be defined as _____.

meta-analysis

An advantage in using T scores is that

none of the scores is negative

A bell-shaped, smooth, mathematically defined curve that is highest at its center is known as a(n)

normal curve

Identify the correlation coefficient developed by Charles Spearman.

rank-order correlation coefficient

A(n) _____ scale has a true zero point.

ratio

Identify the scale by which all mathematical operations can meaningfully be performed.

ratio scale

In a distribution, a straightforward, unmodified accounting of performance that is usually numerical is known as a _____.

raw score

The nature and extent to which symmetry is absent in a distribution is known as _____.

skewness

A raw score that has been converted from one scale to another scale, where the latter scale has some arbitrarily set mean and standard deviation is known as a(n) _____.

standard score

During World War II, researchers developed a standard score with a mean of 5 and a standard deviation of approximately 2 known as a _____.

stanine

The area on a normal curve between 2 and 3 standard deviations above the mean is referred to as a(n) _____.

tail

______ is an indication of how scores in a distribution are scattered or dispersed.

variability

Identify the formula to calculate a z score when the mean (XX) and the standard deviation (s) is known.

z = X−X/s

The conversion of a raw score into a number indicating how many standard deviation units the raw score is below or above the mean of a distribution results in a(n) _____.

z score