In an Experiment to Study the Effectiveness of Three Different

question 21

Multiple Choice

In an experiment to study the effectiveness of three different teaching programmes on children's achievement in mathematics, what might not be an appropriate covariate?

• A) IQ
• B) Mathematical aptitude
• C) Age
• D) Height*

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Definitions:

One-Group Pretest-Posttest Uninterpretable Design

Refers to a simplistic experimental design where a single group of subjects is tested before and after an intervention without a control group, making causal interpretations difficult.

Internal Validity

The extent to which a study can demonstrate a causal relationship between variables, free of confounding factors.

Random Assignment

is a process used in experimental designs to allocate participants to different groups in a study by chance, minimizing pre-existing differences among those groups.

Pretest-Posttest Nonequivalent Groups Design

A quasi-experimental design involving two groups that are not randomly assigned, with both groups measured both before (pretest) and after (posttest) a treatment or intervention.