Psychological Psychological Testing : principles ofTesting : principles ofpsychological testingpsychological testing

Psychological Psychological Testing : principles ofTesting : principles ofpsychological testingpsychological testing

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Psychological Testing Psychology cannot attain the certainty

and exactness of the physical sciences, unless it rests on a foundation of experiment and measurement. A step in this direction could be made by applying a series of mental tests and measurements to a large number of individuals. The results would be of considerable scientific value in discovering the constancy of mental processes, their interdependence, and their variation under different circumstances.

What is a test? A psychological act with respect to

assessment is defined as being “the use of measures to assess mental, cognitive, or behavioural processes and functioning, intellectual or cognitive ability or functioning, aptitude, interest, emotions, personality, psycho physiological functioning, or psychopathology.”

Measure constructs Try to quantify traits and behaviour Represent the individual characteristic of the

person on the construct Differences in scores should represent differences in the construct

Principles of psychological testing

1. Standardization2. Objectivity3. Test norms4. Reliability 5. Validity6. Validity generalization

Standardization

• The consistency and uniformity of the conditions and procedures for administering psychological test.

• Instruction • Amount of time • Testing procedure • Situation • Environment

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Objectivity• Objectivity refers primarily to the scoring of

the test results. • Test to be scored objectively, it is necessary

that everyone scoring the test obtained the same results.

• Objective tests – free from personal bias. (MCQ - closed ended)

• Subjective tests – influence by the • personal bias (easy questions – • open ended)

Test norms• The distribution of test score of a large group of

people similar in nature to the job applicants being tested.

• Standardization sample – the group of subjects used to establish test norms.

• The scores of the standardization sample serve as the point of comparison for determining the relative standing of the person being tested.

Individual score 82 on mechanical ability

Reliability• The consistency or stability of a

response on a psychological test.• The reliability of a measure indicates

the degree to which an instrument consistently measures a particular skill, knowledge base, or construct.

• Exa. Cognitive ability mean score -100 & next week 72

• Reliability is a precondition for • validity

Types of Reliability• Inter-rater (scorer) reliability

• Inter-item reliability

• Test-retest reliability

• Split-half & alternate forms reliability

Inter-rater or scorer Reliability

• Rubric scores can be obtained and applied to the learning outcomes, and indicate the degree of student achievement within the program/course consistentlyconsistently

Inter-Item Reliability• Items that measure the same

learning outcomes should consistentlyconsistently exhibit similar scores

Test-retest reliability

• A way to determine test reliability that involves administrating new test twice to the same group of subjects and correlating the two sets of scores.

• +.90, + 35

Split-half & alternate forms reliability

• A way to determine test reliability that involves administrating a new test to a group of subjects, dividing in half the total number of items and correlating the two sets of scores.

Validity

• The validity of a measure indicates to what extent items measure some aspect of what they are supposed to measure.

• Exam. Intelligence, Memory, Attitudes etc.

Types of Validity

• Face Validity

• Content Validity

• Construct Validity

• Criterion-Related Validity

Face Validity• It looks like a test of

*#%*• Not validity in a

technical sense• A subjective impression

of how well test items seems to be related to the requirement of a

job

Content Validity• A type of validity that

assesses test items to ensure that they adequately sample the skills that test is designed to measure.

• Domain Sampling

• The simple summing or averaging of dissimilar items is inappropriate

Construct Validity• Indicated by

correspondence of scores to other known valid measures of the underlying theoretical trait

• Discriminant Validity

• Convergent Validity

Criterion-Related Validity• Represents

performance in relation to particular tasks of discrete cognitive or behavioral objectives

• A minimum validity coefficient of .70 is generally considered as an acceptable level of construct or criterion-related validity

There are two measures of criterion related validity

• Predictive Validity - Which indicates the degree to which scores predict future performance

• Concurrent validity - Which indicates the degree to which scores correlate with other concurrently administered, valid, criterion-based measures that directly measure the same thing.

Validity generalization

• The idea that tests valid in one situation may also be valid in another situation.

Administering psychological tests

• Psychological test can be categorized in two way

1.How they are constructed and administered

2. The skills and abilities they are designed to measure

Individual and group tests

Computerized adaptive tests

Speed and power tests

Individual and Group tests

• Individual Tests – psychological tests designed to be administered to one person at a time

• Group tests - psychological tests designed to be administered to a large number of people at the same

• time.

Computerized adaptive tests

• A means of administering psychological tests in which an applicant’s response to an item determines the level of difficulty of succeeding items.

Speed and Power tests

• Speed tests – tests that have a fixed time limit, at which point everyone taking the test must stop.

• Power tests – tests that have no time limit. Applicants are allowed as much time as they need to complete the test.

Types of Psychological Types of Psychological Tests Tests

Limitations ofLimitations ofPsychological TestingPsychological Testing

Types of Psychological Types of Psychological Tests Tests

Limitations ofLimitations ofPsychological TestingPsychological Testing

Types of Psychological Tests

• Cognitive abilities• Interests• Aptitudes• Motor skills• Personality • Integrity tests

Cognitive abilities• Intelligence tests • Otis self administering test –

mental ability• Wonderlic personnel test- general

mental ability• Beta examination test – subtype –

mazes, coding, paper from boards picture completion, clerical checking, picture absurdities

Interests• Interest test – to assess person’s

interest and preferences. • For assessing career counseling.

• Strong interest inventory• Kuder occupational inventory

Aptitudes test • Psychological tests to measure

specific ability such as mechanical or clerical skill.

Limitations of Psychological Testing

• Uncritical Use• Rejection of

Qualified Candidates

• Faking• Attitudes Toward

Testing– Lawsuits

• Ethical Issues– Test Users– Test Security– Test Interpretation– Test Publication

• Privacy Issues– What can and

should be asked?