Demonstrations and activities for Psyc 220

Walter vom Saal

This is a preliminary list of some of the demonstrations and activities we will do in Psyc 220. It does not necessarily include all that we will do.

More details for each demonstration or activity are available by clicking the appropriate links in the left column below.

SUGGESTION #1: USE SAVE, NOT OPEN. in order to keep a copy of these sheets on your own computer (or on your p drive), when you click on the item below you should not select OPEN, but instead select SAVE, and then save the sheet on your computer (or p drive) using a name that is meaningful to you..

SUGGESTION #2: SAVE TWO COPIES. You also may want to open the file and then select File > Save As to save it under a second, different name. For example, you might save the original file as "USING EXCEL - ORIGINAL" and save another copy as "USING EXCEL - WORKING COPY." You could then keep the first version as the original and the second version as one you want to modify and play with.

 

Title Description and notes
Using Excel

Combines several items. First, some instructions on using Excel to compute functions (such means, tests, or correlations); second, some instructions on formatting cells in Excel spreadsheets; and third, some examples of potentially misleading statistics based on changing axes.
Demo: examples of T-tests uses a data set to illustrate the use of a T-test to calculate the statistical significance of a difference between means. Then different changes are made to the data set to see what happens to the statistical significance. These include changes in variance, and changes in the number of observations.
Correlations #1 preliminary demonstration of some correlations
Correlations #2 more demonstration of some correlations. NOTE: until I get this changed, click on "Don't Update" when this opens.
The meaning of statistical significance This is a discussion of what it means to say something is "statistically significant." It expands on the material in the text. It will be reviewed in class. You are responsible for understanding this material.
Statistical significance of correlations This is a chart showing how large a correlation coefficient must be to be statistically significant. The chart shows one-tailed probabilities, so multiply the probabilities along the top row of the chart by 2 to get 2-tailed probabilities.
T-test vs. correlation This Excel spreadsheet uses several related data sets to illustrate the difference between a t-test and a correlation. The example used is a group of students who took an SAT test twice, and questions are asked about the relation between scores on Test 1 and scores on Test 2.
confounding practice examples Examples from class members. Descriptions of research studies to practice identifying independent variables, dependent variables, confounding variables, and extraneous variables.
Interaction practice questions Stay up all night having fun with these questions to practice your skill at examining 2x2 tables and determining main effects and interactions.

4/11/05