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Explain how a dependent-samples -test reduces pretest and posttest scores to a single set of difference scores. In your explanation, describe what a hypothetical population mean of represents in the context of evaluating the effectiveness of the training program.
Question: Explain how a dependent-samples -test reduces pretest and posttest scores to a single set of difference scores. In your explanation, describe what a hypothetical population mean of represents in the context of evaluating the effectiveness of the training program.
Sample answer: A dependent-samples -test evaluates paired pretest and posttest scores by subtracting each participant's pretest score from their posttest score, creating a single difference score for each individual. The researcher then performs a one-sample -test on these difference scores. In this setup, a hypothetical population mean of represents the null hypothesis, stating that the training program has no effect, meaning there is no difference between the pretest and posttest calorie estimates in the population.
Key points:
- Pretest and posttest scores are subtracted to create difference scores for each participant.
- A one-sample -test is conducted on these difference scores.
- The hypothetical population mean of represents the null hypothesis (no training effect or change).
Rubric: To receive full credit, the student must: 1. Explain that pretest and posttest scores are subtracted to construct a single set of difference scores. 2. State that a one-sample -test is performed on these difference scores. 3. Clarify that the population mean of represents the null hypothesis of no change or no training effect.
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Research Methods in Psychology - 4th American Edition @ KPU
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In the calorie-estimation pretest-posttest example, what is the computed score for the dependent-samples -test?
In a dependent-samples -test, a researcher fails to reject the null hypothesis when the computed score is less extreme than the critical value, indicating the result is not statistically significant.
Match each value or outcome from the calorie-estimation dependent-samples -test example to its correct role or interpretation in the analysis.
In the provided example, the researcher evaluates the effectiveness of the training program by comparing the computed score () to the critical value (). Because the calculated score is less extreme than the critical value, the researcher fails to reject the _____ hypothesis.
Order the steps a researcher must perform and evaluate to determine if the calorie-estimation training program is statistically significant, from the initial calculation of difference scores to the final hypothesis decision.
In the provided pretest-posttest study evaluating the training program, what is the critical value for the one-tailed dependent-samples -test with degrees of freedom?
Explain how a dependent-samples -test reduces pretest and posttest scores to a single set of difference scores. In your explanation, describe what a hypothetical population mean of represents in the context of evaluating the effectiveness of the training program.
Based on the provided statistical results, decide whether the researcher should reject or fail to reject the null hypothesis, and justify what this decision means regarding the effectiveness of the training program.
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