Psychometrics
An introduction
Second edition
R. Michael Furr, Verne R. Bacharach
, Psychometrics An Introduction
Second edition R.M. Furr & V.R. Bacharach
Chapter 1: Psychometrics and the Importance of Psychological Measurement
Observable behavior and unobservable psychological attributes
Psychological tests are used as instruments to measure observable events in the physical world.
Typically, this is some kind of behavior and is conducted for two purposes. First, because of the
interest in specific behavior in its own right (like the way facial expression affects the perception of
emotions). Second, and much more commonly, behavioral scientists observe human behavior as a
way of assessing unobservable psychological attributes such as intelligence, depression, knowledge
etc.
In testing working memory, three things should be noticed:
1. An inference from an observable behavior to an unobservable psychological attribute is
made. We assume that the particular behavior that we observed was in fact a measure of
working memory.
2. For our interpretation of digit recall scores to be considered valid, the recall task had to be
theoretically linked to working memory.
3. When measuring working memory, we assume that working memory is more than a figment
of our imagination.
Psychological tests: definition and types
What is a psychological Test?
According to Cronbach (1960), a psychological test “is a systematic procedure for comparing the
behavior of two or more people”. The definition includes three important components:
1. Tests involve behavioral samples of some kind
2. The behavioral samples must be collected in some systematic way
3. The purpose of the test is to compare the behaviors of two or more people.
Also the comparison of performance by the same individuals at different points in time can be
included in this definition.
Types of tests
Tests can vary in content, in the regard to the type of response required (open-end test, closed-
ended test), in the methods used to administer them (individual or group tests).
Another common distinction concerns the intended purpose of test scores. Psychological tests are
often categorized as either criterion referenced or norm referenced.
Criterion referenced tests are often seen in setting in which a decision must be made about a
person’s skill level. A fixed, predetermined cutoff tests score is established. Two groups are made:
1. Those whose performance exceeds the performance criterion
2. Those whose performance does not.
Norm referenced tests are used to compare a person’s test score with scores from a reference
sample, or a normative sample. A person is compared with other people.
Another common distinction is between speeded tests and power tests. Speeded tests are time-
limited tests. The number of questions answered are counted. Power tests are not time limited,
examinees are expected to answer all the questions (in contrast to speeded tests).
An introduction
Second edition
R. Michael Furr, Verne R. Bacharach
, Psychometrics An Introduction
Second edition R.M. Furr & V.R. Bacharach
Chapter 1: Psychometrics and the Importance of Psychological Measurement
Observable behavior and unobservable psychological attributes
Psychological tests are used as instruments to measure observable events in the physical world.
Typically, this is some kind of behavior and is conducted for two purposes. First, because of the
interest in specific behavior in its own right (like the way facial expression affects the perception of
emotions). Second, and much more commonly, behavioral scientists observe human behavior as a
way of assessing unobservable psychological attributes such as intelligence, depression, knowledge
etc.
In testing working memory, three things should be noticed:
1. An inference from an observable behavior to an unobservable psychological attribute is
made. We assume that the particular behavior that we observed was in fact a measure of
working memory.
2. For our interpretation of digit recall scores to be considered valid, the recall task had to be
theoretically linked to working memory.
3. When measuring working memory, we assume that working memory is more than a figment
of our imagination.
Psychological tests: definition and types
What is a psychological Test?
According to Cronbach (1960), a psychological test “is a systematic procedure for comparing the
behavior of two or more people”. The definition includes three important components:
1. Tests involve behavioral samples of some kind
2. The behavioral samples must be collected in some systematic way
3. The purpose of the test is to compare the behaviors of two or more people.
Also the comparison of performance by the same individuals at different points in time can be
included in this definition.
Types of tests
Tests can vary in content, in the regard to the type of response required (open-end test, closed-
ended test), in the methods used to administer them (individual or group tests).
Another common distinction concerns the intended purpose of test scores. Psychological tests are
often categorized as either criterion referenced or norm referenced.
Criterion referenced tests are often seen in setting in which a decision must be made about a
person’s skill level. A fixed, predetermined cutoff tests score is established. Two groups are made:
1. Those whose performance exceeds the performance criterion
2. Those whose performance does not.
Norm referenced tests are used to compare a person’s test score with scores from a reference
sample, or a normative sample. A person is compared with other people.
Another common distinction is between speeded tests and power tests. Speeded tests are time-
limited tests. The number of questions answered are counted. Power tests are not time limited,
examinees are expected to answer all the questions (in contrast to speeded tests).
