Validity

Reliability

The consistency of a measure, leading to reliable and replicable studies.

Replicability

Enhanced by clear operational definitions and appropriate sampling techniques.

Simple random sampling

Each individual in the population has an equal chance of being included.

Systematic sampling

Individuals are selected from the population using a fixed interval frame.

Stratified sampling

Used for heterogeneous populations to represent differences proportionally.

Cluster sampling

Employed when the population is widely dispersed and can be subdivided into clusters.

Convenience sampling

Participants are recruited wherever possible without a specific system.

Volunteer sampling

Participants volunteer following advertisement, often linked to snowball sampling.

Validity

Refers to the nature of the construct measured and its interpretations and uses.

Reliability vs

Reliability is a quantitative property of test responses, while validity is about the interpretation of test scores.

Content validity

Based on the evaluation of subjects, topics, and content covered by test items.

Criterion related validity

Obtained by evaluating the relationship of scores on the test to other measures.

Construct validity

Involves a comprehensive analysis of how scores relate to other measures within a theoretical framework.

Face validity

Judgment on how relevant test items appear to be, especially in the early stages.

Factor analysis

Examines patterns in variables to condense information into underlying dimensions.

Ceiling effects

When a significant percentage of participants score the maximum possible score.

Floor effects

When a considerable percentage of participants obtain the minimum available score.

Exploratory vs

Different types of factor analysis approaches.

Bartlett's test of sphericity

Tests if the correlation matrix departs significantly from an Identity Matrix.

Kaiser Meyer Olkin level

Measure of sampling adequacy for factor analysis, typically > 0.7.