PSYC FPX 4700 Assessment 3 Hypothesis Effect Size Power and Tests

The null hypothesis can be rejected at α = .05. Typically, the null hypothesis posits that the means of the two independent groups being compared do not significantly differ. In this case, the negative t-value (-2.580) indicates that the mean for Group 1 is lower than that for Group 2. The alpha level of 0.05 is less than the p-value of 0.024.

When the p-value is less than the alpha level, it suggests that the likelihood of observing such a substantial difference between the groups by chance alone is less than 5%. In other words, there is strong evidence that the difference between the two groups is not merely due to random variation.

Therefore, based on these results, we can reject the null hypothesis and conclude that there is a significant difference between the means of the two independent groups being examined.

Problem Set 3.9: Independent t Test using Excel

Criterion: Calculate an independent samples t test in Excel.

Data: Use the following data:

Depression Scores:

Group 1: 34, 25, 4, 64, 14, 49, 54
Group 2: 24, 78, 59, 68, 84, 79, 57

Instructions: Complete the following steps:

1. Open Excel.
2. Enter the data from above in a new tab. Use column A for Group 1 and column B for Group 2. Enter 1 in Cell A1 and 2 in Cell B1.
3. Below the labels, input the data for each group.
4. Select t-Test by clicking on Data Analysis: Two-Sample Assuming Equal Variances. Click OK.
5. Enter $A$2:$A$8 into Variable 1 Range. Alternatively, you can highlight your data for Group 1 by clicking the graph icon to the right of the box.
6. Enter $B$2:$B$8 into the Variable 2 Range field.
7. Click OK. A new tab will open with your results.
8. Return to your files. Select t-Test by clicking on Data Analysis: Two-Sample Assuming Unequal Variances. Click OK.
9. Enter $A$2:$A$8 into Variable 1 Range. Alternatively, click the graph icon to the right of the box and highlight your data for Group 1.
10. In Variable 2 Range, enter $B$2:$B$8.
11. Click OK. A new tab will open with your results.
12. Below, copy the results of the two t-tests.

T-Test: Two-Sample Assuming Equal Variances

T-Test: Two-Sample Assuming Unequal Variances