PSYC 355 SPSS Homework 1 Single-Sample t-Tests and Paired-Sample t-Tests | Complete Solution

SPSS Homework 1 Instructions

Single-Sample t-Tests and Paired-Sample t-Tests

Part 1:

Note that for all problems in this course, the standard cutoff for a test of significance will be p < .05 unless otherwise noted in the problem.

Homework files are found in Blackboard Course Content > Syllabus and Assignment Instructions > Assignment Instructions > SPSS Homework 1 > SPSS Homework Files (select the particular number for the module/week you are working on). Always use the Blackboard files instead of the files on the Green & Salkind website as some files have been modified for the purposes of this course.

1. Single-Sample t-Test: Based on Green & Salkind - Lesson 22, Exercises 1–4 (Mod1_Lesson 22 Exercise File 1), but follow the instructions below instead.

1. A total score variable is included in the data file in Blackboard (“tot_score”), so you do not have to compute it. Use this variable as your dependent variable.

2. The test value for the single-sample t-test is 2 (1/4 of 8, or the score which a student would achieve by chance). Use 2 as the test value when running the analysis for this exercise.

3. Conduct a single-sample t-test on the total score variable. Paste the output into your Word document and type in the answers to the following questions underneath the output: (2 pts for output)

1. Mean algebra score (2 pts)
2. t-test value (2 pts)
3. p value (significance) of the test (2 pts)

4. Write a Results section in current APA style based on your analyses. (3 pts)

5. Create a histogram that demonstrates the distribution of scores. Be sure to correctly label the X and Y axes. (3 pts)

2. Green & Salkind: Lesson 23, Exercises 6–8: (Lesson 23, Exercise File 1)

The following helpful tips are numbered to correspond with the exercise number to which they refer within the Green & Salkind text:

6. Instead of identifying these values on your output, as the text states, write them into your Word file as written answers for #6 a, b, c, and d. (2 pts for output and 2 pts each for a–d)

7. All homework “Results sections” must follow the example given in the Course Content document “Writing Results of Statistical Tests in Current APA Format” (Note: you do not have to refer to a figure). (4 pts)

8. You will create the boxplot here instead of in the Results section. (2 pts)

Part 2:

1. A school psychologist administers an interview assessment that screens for possible post-traumatic stress disorder (PTSD) to school children who live in an area that was recently affected by a natural disaster. She assumes that children in this area have higher scores than children in the general population, who normally score a 2.3. The table on the following page shows the scores for a particular class of children at the school. Using the table, enter the data into a new SPSS file and conduct a single sample t-test to evaluate whether or not these children scored higher than the general population.

The steps will be the same as the ones you have been practicing in Part 1 of the assignment—the only difference is that you are now responsible for creating the data file as well. Remember to name and define your variables under the “Variable View,” then return to the “Data View” to enter the data. (2 pts)

2. Write a Results section in current APA style describing the outcome. All homework “Results sections” must follow the example given in the Course Content document “Writing Results of Statistical Tests in Current APA Format” (Note: you do not have to refer to a figure). (4 pts)

3. A math teacher wants to evaluate whether or not a new method of teaching leads to improved scores on a geometry test. To test this claim, she administers similar geometry tests to 16 students before and after they have been introduced to the new method. She decides to use a two-tailed test to provide for detecting results in the opposite direction, just in case. Using the table below, enter the data into a new SPSS data file and test the math teacher’s claim using a paired-samples t-test).

The steps will be the same as the ones you have been practicing in Part 1 of the assignment—the only difference is that you are now responsible for creating the data file as well. Remember to name and define your variables under the “Variable View,” then return to the “Data View” to enter the data. (2 pts)

4. The null hypothesis for this scenario can be written as follows: “There is no difference between mean test scores before and after the introduction of the geometry teaching method (M before = M after).” Based on your results, should this hypothesis be accepted or rejected, and why? Write your answer in sentence form. (2 pts)

Submit this assignment by 11:59 p.m. (ET) on Monday of Module/Week 1.