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Imagine a researcher replicates this study with new samples of the same size and finds a between-groups mean square () of 6,022.30 and a within-groups mean square () of 602.23. Using the critical value of 3.467, calculate the new ratio and state whether the researcher should reject the null hypothesis.
Question: Imagine a researcher replicates this study with new samples of the same size and finds a between-groups mean square () of 6,022.30 and a within-groups mean square () of 602.23. Using the critical value of 3.467, calculate the new ratio and state whether the researcher should reject the null hypothesis.
Sample answer: The new ratio is calculated by dividing by , which is . Since the computed ratio of 10.00 exceeds the critical value of 3.467, the researcher should reject the null hypothesis.
Key points:
- Calculates the new ratio as 10.00 using .
- Applies the decision rule by comparing the calculated ratio (10.00) to the critical value (3.467).
- Concludes that the researcher should reject the null hypothesis.
Rubric: Students should show the calculation of the new F ratio (10.00) and correctly apply the decision rule to reject the null hypothesis because the computed F value is greater than the critical value (3.467).
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Research Methods in Psychology - 4th American Edition @ KPU
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Imagine a researcher replicates this study with new samples of the same size and finds a between-groups mean square () of 6,022.30 and a within-groups mean square () of 602.23. Using the critical value of 3.467, calculate the new ratio and state whether the researcher should reject the null hypothesis.