Psychology: Reliability and Validity

Questions and Answers

Which of the following statements about reliability is true?

A test cannot be valid unless it is reliable. (correct)

All tests are both reliable and valid.

A test can be reliable but not valid. (correct)

More items result in lower reliability.

A test can be valid but not reliable.

False

Match the types of reliability with their descriptions:

Test-Retest = Testing at two different times Parallel Forms = Comparing two forms with the same attributes Internal Consistency = Items in a test measure the same construct Inter Rater = Judges evaluate the same behavior

What is 'Test-Retest' reliability?

Testing at two different times with the same subjects. Signup and view all the answers

What does 'Concurrent Validity' measure?

Simultaneous evaluation of a test's validity. Signup and view all the answers

Face Validity only looks at the appearance of a test.

True Signup and view all the answers

Which of the following is a type of internal validity threat?

All of the above Signup and view all the answers

What is the purpose of Item Analysis?

To evaluate the effectiveness and quality of test items. Signup and view all the answers

The __________ effect refers to changes in behavior due to awareness of being studied.

Hawthorne Signup and view all the answers

In a Double Blind Experiment, who does not know which group the participants are in?

Both the subjects and experimenters Signup and view all the answers

Study Notes

Reliability and Validity in Testing

Greater number of items in a test enhances its reliability.
A test can be reliable but may not be valid; however, it cannot be valid unless it is reliable.
Reliability refers to consistent test results from the same test-taker over time.

Types of Reliability

Test-Retest Reliability: Evaluates stability by testing at two different times.
Parallel Forms Reliability: Compares two different forms of a test measuring the same attributes.
Internal Consistency Reliability: Assesses if items within a test measure the same construct.
- Split-Half Reliability: Divides the test into halves and compares scores.
- Cronbach's Alpha: Measures reliability for tests with multiple-choice answers (polytomous).
Inter-Rater Reliability: Evaluates consistency among different evaluators using Kappa statistics.

Validity in Testing

Validity determines if a test measures what it intends to measure (e.g., intelligence tests measure intelligence).

Types of Validity

Criterion Validity: Assesses performance against a criterion (e.g., predictive validity using GPA to evaluate entrance exams).
Content Validity: Judged by experts on how well the test measures content.
Construct Validity: Measures abstract variables based on conceptual frameworks.
Convergent Validity: Tests relationships with similar constructs (e.g., love).
Divergent Validity: No correlation with unrelated variables.
Face Validity: Assesses the external appearance of the test.

Threats to Internal Validity

History: External events affecting test-takers before taking the test.
Maturation: Internal changes over time impacting results, particularly in longitudinal studies.
Testing Effects: Impact of prior testing on scores (practice effect).
Instrumentation: Variability in the administration and materials used in tests.
Statistical Regression: Tendency for extreme scores to move towards the mean.
Selection: Lack of random assignment can lead to biased results.
Subject Mortality: Loss of participants from a study can skew results.

Measurement Techniques

Random error is unpredictable, while systematic errors can be addressed.
Classical Test Score Theory addresses measurement errors and aims for standardized testing.

Experimental Designs

Within-Subjects Design: Same subjects participate in multiple conditions.
Between-Subjects Design: Each subject participates in one condition only.
Matched Groups Design: Groups are matched based on characteristics.
Mixed Design: Combines within-subjects and between-subjects elements.
Factorial Design: Involves two or more independent variables.

Additional Concepts

Reliability estimates in clinical settings should be ≥ 0.90, while those in industrial settings should be ≥ 0.70.
Hypotheses:
- Alternative Hypothesis indicates significant differences.
- Null Hypothesis indicates no significant differences.
Item Analysis: Evaluates the effectiveness of test items based on difficulty and discriminability.

Non-Experimental Approaches

Phenomenology: Studies lived experiences with minimal manipulation.
Case Studies: Provide detailed accounts of individual or group experiences.
Field Studies: Observe behaviors in natural settings.
Archival Studies: Analyze existing records for new insights.
Qualitative Research: Focuses on observations and narratives rather than quantitative data.

Experimental Controls

Single Blind Experiments: Subjects are unaware of group assignments to reduce bias.
Double Blind Experiments: Neither subjects nor experimenters know group assignments to avoid bias.
ANOVA: Used to determine significant differences among three or more groups.
Norm-Referenced Testing: Compares individual scores to a broader population.
Classified Tests:
- Class A: General quizzes.
- Class B: Personality and intelligence assessments.
- Class C: Individualized intelligence and projective tests.

Description

This quiz explores the concepts of reliability and validity in psychological testing. Participants will learn about different types of reliability, including test-retest and temporal consistency, as well as the distinction between a test's reliability and its validity. Test your understanding of these crucial assessment principles.