# t Tests

t Tests

See the Resources area for links to resources that you will use for this assignment:

You will complete this assignment using the DAA Template.

Read the SPSS Data Analysis Report Guidelines for a more complete understanding of the DAA Template and how to format and organize your assignment.

Refer to the IBM SPSS Step-By-Step Guide: t Tests for additional information on using SPSS for this assignment.

If necessary, review the Copy/Export Output Instructions to refresh your memory on how to perform these tasks. As with your previous assignments, your submission should be in narrative format with supporting statistical output (table and graphs) integrated into the narrative in the appropriate places (not all at the end of the document).

You will analyze the following variables in the grades.sav data set:

gender

gpa

Step 1: Write Section 1 of the DAA.

Provide the context of the grades.sav data set.

Include a definition of the specified variables (predictor, outcome) and corresponding scales of measurement.

Specify the sample size of the data set.

Step 2: Write Section 2 of the DAA.

Analyze the assumptions of the t test.

Paste the SPSS histogram output for gpa and discuss your visual interpretations.

Paste SPSS descriptives output showing skewness and kurtosis values for gpa and interpret them.

Paste SPSS output for the Shapiro-Wilk test of gpa and interpret it.

Report the results of the Levene test and interpret it.

Summarize whether or not the assumptions of the t test are met.

Step 3: Write Section 3 of the DAA.

Specify a research question related to gender and gpa.

Articulate the null hypothesis and alternative hypothesis.

Specify the alpha level.

Step 4: Write Section 4 of the DAA.

Paste the SPSS output of the t test.

Report the results of the SPSS output using proper APA guidelines (refer to the Unit 8 Introduction and the “Results” example from the Warner text in Chapter 5). Include the following:

t.

Degrees of freedom.

p value.

Effect size.

Interpretation of effect size.

Means and standard deviations for each group.

Mean difference.

95% confidence interval of the difference of sample means.

Interpret the results against the null hypothesis.

Step 5: Write Section 5 of the DAA.

Discuss the implications of this t test as it relates to the research question.

Conclude with an analysis of the strengths and limitations of the t test.

Submit your DAA Template as an attached Word document in the assignment area.

Resources

t Tests Scoring Guide.

DAA Template.

SPSS Data Analysis Report Guidelines.

IBM SPSS Step-by-Step Guide: t Tests.

Copy/Export Output Instructions.

APA Style and Format.