Practice guide for the Final Lab Practical, Spring 2016

Instructions for the actual Lab Practical:

You have carried out a series of exercises in SPSS during lab over the last months, guided step-by-step by your text and handouts. You have been asked to practice using SPSS so that you can complete similar exercises on your own, without the detailed guidance provided by your text. Now it is time for you to demonstrate your abilities.

You will have up to 1.5 hours to complete the exercises below. You will be asked to answer questions on this document and to copy and paste from SPSS onto this document. Once you have finished with the lab practical, you will send this file to Dr. Reid () for grading.

Practice Guide:

  1. Using Practice Data Set 2 on the course website, conduct a single-sample t-test. Assuming that the mean salary in the United States if $25,000, determine whether the mean salary of the participants is significantly greater than this mean salary. Note that this has a one-tailed hypothesis.
  2. Copy and paste the “One-Sample Test” table here.
  1. Write the results of the t-test in correct APA format (in the paragraph style necessary for a Results section), using the obtained values from your results.
  1. Conduct an independent-samples t-test using the Sample.sav data set located on the course website. The dependent variable will be “grade” and the two groups will be defined by the variable “morning” (0 for non-morning and 1 for morning).
  2. Copy and paste the “Independent Samples Test” table here.
  1. Write the results of the t-test in correct APA format (in the paragraph style necessary for a Results section), using the obtained values from your results.
  1. Conduct a paired-samples t-test using the data set Grades, located on the course website. Compare the scores on the Pretest with those from the Final.
  2. Copy and paste the “Paired Samples Test” table here.
  1. Write the results of the t-test in correct APA format (in the paragraph style necessary for a Results section), using the obtained values from your results.
  1. Conduct a one-way ANOVA using the data set Grades, located on the course website. Determine whether the instructors differed from one another on their influence on final exam grades. Use “Instruct” as the factor (independent variable) and “final” as your dependent variable. Include the Tukey (HSD) post hoc test.
  2. Copy and paste the “Descriptives” and “ANOVA” tables here.
  1. Verbally (in writing) explain the results of the Tukey HSD post hoc test.
  1. Write a summary of each of the statistical tests in correct APA format (in the paragraph style necessary for a Results section), using the obtained values from your results.
  1. Conduct a factorial ANOVA using the data set Practice Data Set 2, located on the course website. Determine whether salaries are influenced by sex, job classification, or an interaction between sex and job classification. Ask SPSS to calculate estimates of effect sizes (in the options menu).
  2. Copy and paste the “Tests of Between-Subjects Effects” table here.
  1. How many hypotheses were tested? . Identify those that were statistically significant.
  1. Summarize each of the statistical tests using the abbreviated format “F( xx,xxx) = xx.x, p = .xxx, ηp2=.yyy” for each test.
  1. Compute a repeated-measures ANOVA using the Grades data set located on the course website. Assign the name “time” as the within-subjects factor. Within the same analysis, calculate the descriptive statistics (under “Options”) for the three tests by using “time” as the variable.
  2. Copy and paste the “Tests of Within-Subjects Effects” table here.
  1. Examining your results, how many separate post-hoc tests would be required to identify significant differences between your groups. Assume you would use a simple paired-sample t-test for the post-hoc tests.
  1. Why it is necessary to adjust the alpha value for these post-hoc tests, and how would you do this?
  1. Summarize your results using the abbreviated format “F( xx,xxx) = xx.x, p = .xxx, ηp2=.yyy”.
  1. Compute a mixed-design ANOVA using the same Grades data set. Use the three tests as within-subjects variables and “Instruct” as the between-subjects factor. Ask SPSS to calculate estimates of effect sizes (in the options menu).
  2. Copy and paste two tables here: the “Tests of Within-Subjects Effects” and the “Tests of Between-Subjects Effects”.
  1. Summarize each of your results using the abbreviated format “F( xx,xxx) = xx.x, p = .xxx, ηp2=.yyy”.
  1. Compute a second mixed-design ANOVA using the same Experiment3D data set, located on the course website. As your within-subjects variable, use the three “fear of stats” scores (“fost1”, “fost2”, “fost3”), and define them as the variable “Time” (producing Time 1, Time 2, Time 3). Your between-subjects variable should be the type of class (“Group”). Click on the Options button to display Descriptive Statistics, Estimates of effect size, and Homogeneity tests. As you evaluate your results, focus on Wilk’s Lambda.
  2. Copy and paste two tables here: the “Multivariate Tests” and the “Tests of Between-Subjects Effects”.
  1. Summarize each of your results using the abbreviated format “F( xx,xxx) = xx.x, p = .xxx, ηp2=.yyy”, and include Wilk’s Lambda where appropriate.

9.  Complete an ANCOVA using the data set Heights located on the course website. You will need to use Factorial ANOVA in this task. Your goal is to determine whether you will see a significant difference between people’s sex and height if you factor out the influence of weight. Therefore, place the variable “Height” as your dependent variable. Set “Sex” as your fixed factor, then “Weight” as your Covariate.

a.  Insert two tables below: “Tests of Between-Subjects Effects”, and “Descriptive Statistics”.

  1. Write the results of the ANCOVA in correct APA format (in the paragraph style necessary for a Results section), using the obtained values from your results.
  1. Complete a MANOVA using the data set Experiment3D located on the course website. Your goal is to determine whether the type of training (“group”) influences confidence scores and exam scores – two variables that may be related to each other. Your two dependent variables are “exam” and “confid3”. The variable “group” will be your fixed factor. Ask SPSS to calculate estimates of effect sizes (in the options menu).

a.  Insert two tables below: “Multivariate tests”, and “Tests of Between-Subjects Effects”.

  1. Does the Multivariate test indicate that Wilk’s Lambda was significant for group?
  1. Summarize your two results using the abbreviated format “F( xx,xxx) = xx.x, p = .xxx, ηp2=.yyy”, (for Wilk’s Lambda and group as a univariate variable in ANOVA).

Note: The format for the following nonparametric tests is slightly different than the questions above.

11.  Chi-Square test of independence:

a.  Carry out the statistical test as described on page 98 of your text. Your data are listed on page 93. Were the results significant? How do you interpret/describe significant results? How do you interpret/describe non-significant results?

b.  Summarize your results using the abbreviated format, including the degrees of freedom.

c.  Complete the Practice Exercise on p. 101. Follow the instructions carefully about data entry – this is the most critical part! What results did you find?

d.  Summarize your results using the abbreviated format, including the degrees of freedom.

12.  Section 7.3 Mann-Whitney U Test:

a.  This test is the non-parametric equivalent of which parametric test?

b.  What question does it evaluate?

c.  Carry out the test as described, creating the data file as described [save it to your computer because you will use and modify this file in the next sections].

d.  Summarize your results using the abbreviated format.

e.  Was the Model Viewer helpful to you as you interpreted the results? What information did it provide?

f.  How should you phrase the results of your findings in the Results section of your (hypothetical) paper?

g.  Carry out the Practice Exercise using Practice Data Set 1 (located on the course website) as described on page 105. You will see that these practice exercises ask you to rely more and more on your own experiences up to this point. This is a goal of the course and a primary focus of your next lab practical. [You can check Appendix D if you need an example of data formatting]. Using the APA format (paragraph style) you have been practicing, describe the results of your test:

13.  Section 7.4 Wilcoxon Test: After reading the description, you should be aware that the terminology in this text is different from that of the Jackson text. Let’s clarify these differences by:

a.  Identify the purpose of the Wilcoxon Test:

b.  Carry out the test. Explain how the Model Viewer helps you understand the results.

c.  Write your results in the format required by APA (in the paragraph style necessary for a Results section).

14.  Section 7.5 Kruskal-Wallis H Test: This test is the nonparametric equivalent of which parametric test?

a.  What question does it ask?

b.  It is designed for how many IVs? How many treatment conditions?

c.  What data type of the IV is required?

d.  What data type of the DV is required? How should it be represented in SPSS?

e.  Carry out the test.

f.  Why are pairwise comparisons required?

g.  Summarize your results using the abbreviated format, including the degrees of freedom.

h.  Did you find significant results? Based on which groups?

15.  Section 7.6. Friedman Test: What is the purpose of this test?

a.  How is the purpose of this test different from the previous test you just completed [the Wilcoxon Test]?

b.  Is this test designed for ratio or interval data? Will it work for ordinal? How about nominal?

c.  Carry out the test.

d.  Summarize your results using the abbreviated format, including the degrees of freedom.

e.  From the output you have read, should this test be appropriate for more than one IV? Justify your opinion.

  1. Practice Exercise: Complete the practice exercise on page 116. You will find the data file on the course website. Phrase your results:

Since this is only a practice test, do NOT email your completed practical to Dr. Reid.

If this were a real practical, you would: Save this Word file temporarily to your desktop under your own name. Then send this complete document to Dr. Reid now (Send Using Email). Please place your name and the words “Final” in the subject line. Ask Dr. Reid to confirm that he has received your document.

Once receipt has been confirmed, delete your Word file and the SPSS files from the desktop. Shut down the computer and turn it off. You are all done!