# The Process of Statistical Analysis in Psychology

# Web Activities

Click on the following links. Please note these will open in a new window.

*Activity 1:*

**Identifying hypotheses and understanding the newly introduced independent samples t test**

Your book discussed the hypothesis for an independent samples *t* test. In this activity, you will apply this information.

Answer the following questions:

- Under what conditions would you use an independent samples
*t*test? - Go to this website: http://www.newsindata.com/home/2017/1/6/drug-overdose-deaths

- Create an independent samples
*t*test hypothesis using the drugs in the graph (as marijuana has 0 for values it is not being analyzed here) in the group.

- Create an independent samples
- What makes a dependent samples
*t*test different from a one-sample*t*test? - In what way are these tests similar?

*Activity 2:*

**Understanding Homogeneity of Variance**

Your book discussed homogeneity of variance. In this exercise, you will practice applying this concept to a collection of data.

Go to this website: http://www.thedurkweb.com/how-sharing-a-bed-with-my-girlfriend-changed-my-sleep/

- What kind of
*t*test would you use to analyze the data? How do you know? - Generate the hypothesis for this
*t*test using the variables named in the graph. - Scroll down to the chart that shows distribution of sleep. What do you think about the homogeneity of variance of the two distributions? Would it meet or violate the assumption?

- If it were violated and the data were in SPSS, what would you do to account for the violation?

*Activity 3:*

**Understanding conceptual differences between t tests: Three choices**

So far your book has discussed three types of *t* tests: one sample and dependent samples. In this activity, you will practice identifying types of *t* tests.

First, in words, what is the hypothesis for a:

- one-sample
*t*test, - dependent samples
*t*test, and - independent samples
*t*test.

Instructions: Go to each of the following links. For each graph shown, identify what type of *t* test would be used to analyze the hypothesis and write the hypothesis in words.

- http://www.newsindata.com/home/2017/2/3/phone-calls-to-congress-are-likely-at-an-all-time-high
- http://www.newsindata.com/school-shootings-this-decade-have-far-surpassed-all-previous-decades/
- http://www.newsindata.com/the-college-gap-no/
- http://www.economist.com/news/asia/21722216-there-was-just-one-fatal-shooting-whole-2015-crime-dries-up-japans-police-hunt

*Assume we are just interested in Japan.