2 stats assignments - READ attachments FIRST

Instructions :

· Please answer each question below, placing the answer underneath each question (please do not do it in a research paper format, with a cover page, etc.).

· Answers should be at least two paragraphs each.

· Below is the link to the book (log-in info will be provided)

1. What is Significant?

a. Define and apply the concept of “statistical significance” versus “practical significance” to something you are working on, or have read about.  

b. Can you have one without the other?  If so, name something that is statistically significant but not practically significant.   How about something that is practically significant but not statistically significant?

c. Which is most important?  Statistical or practical significance?

2. Contingency Tables (or Crosstabs)

a. You will see contingency tables used often to compare two categorical variables (nominal and/or ordinal).   To report results, you would simply compare the differences in percentages across categories.   To establish if there is a statistical relationship (remember these are samples with margins of error), you could use the chi-square test.  Do you have any contingency table examples to offer?

b. Why would you want to control for competing hypotheses (see the discussion in Chap. 16 of the textbook, Applied Statistics)?  Give an example.  Can you guess why multiple regression is the answer to this, in the long run?

[link to the textbook: https://www.vaultebooks.com/#/user/signin]

3. Comparing 2 Means and Chi-square Tests

a. One of the most commonly used statistical techniques is the comparison of two means, also known as the t-test (for this you need quantitative variables, or interval level data to compare across two categories - find it on the RoadMap!).