CompTIA Data+ (DA0-002)Data AnalysisEasy
A data analyst is evaluating the effectiveness of a new marketing campaign by comparing the average customer engagement scores before and after the campaign. The scores are collected from the SAME group of customers. Which statistical test should the analyst use to determine if there is a significant difference?
- AIndependent Samples t-test
- BANOVA
- CChi-square test
- DPaired Samples t-test
Show answer & explanationAnswer & explanation
Correct answer: D. Paired Samples t-test
When comparing two means from the same group of subjects measured at two different times or under two different conditions, a Paired Samples t-test is appropriate. This test accounts for the dependency between the 'before' and 'after' measurements.
Why the other options are wrong
- A. This test is used for comparing means from two independent groups, not the same group measured twice.
- B. ANOVA is used for comparing means of three or more groups, or for comparing multiple factors simultaneously.
- C. The Chi-square test is used for analyzing categorical data, not for comparing means of continuous scores.
Paired Samples t-test
A statistical test used to determine if there is a significant difference between the means of two related groups or samples. It is typically applied when the same subjects are measured twice (e.g., before and after an intervention).
- Compares means of two related samples.
- Accounts for dependency between measurements.
- Requires continuous data for the dependent variable.
Memory trick: Same subjects, paired comparison, that's the t-test you've aired!