LANCER STATS PAGE

TWO VARIABLE STATISTICS

1. These pages are a good companion to your reading in Bivariate Statistics

2. And this is the [Chapter 14]Hyper-stats pages on regression and hypothesis tests on the slope of the regression line and the correlation coefficient.

3. This is the link from SticiGui (That's pronounced sticky-gooey) about Scatter plots that we used in class. Use it to review. [note:these may take a little time to load because they are Java Script aplets ... wait, it is worth it.

4. Here is a good interactive Java from the Hyperstats folks that will help you understand how the various components of correlation and regression are related.

5. This applet lets you try to guess the regression line and shows the mean squared error {the sum of the squares of the residuals divided by n-2} for each line you draw. This is a predictor of the variance of the residuals, and is the square of the SE (standard error of the estimate).

6. Challenge the world, can you pick correlations better than the next guy(girl)... Guessing Correlation

7. Here is a collection of games.. and On one you can practice guessing correlation coefficients from scatter plots.

8. You can see the effect of the Standard error of the Estimate, sort of the standard deviation of the residuals, in this applet. Click on "Animate SE" and watch what happens to the spread of the points... also look at the bar on the right that shows "explained" and "unexplained" errors. This is the ratio (explained/total) that we call R2.

9. This applet draws repeated sample regression lines from a given population and reminds us that the regression line we find is a sample from all the lines we might get by sampling from the population. Try setting the sample size to 10 and the number of samples to 25 or 50 or some other moderatly large number. When the sampling is done you will see a popup with the mean of the slopes (and the intercepts) and a graph of all the sample lines on a single graph. This image should help you understand the hypothesis tests and confidence intervals about regression lines.

10. And here are some Multiple Choice Practice Problems on Correlation. These are now pdf files, so if you don't have acrobat on your machine.. see me or send an email.

11. And some more MC questions about Least Squares Regression

A glossary of Statistical Terms from SticiGui
Hyper-Stats Glossary

This video will show you how to work with regression lines on the TI-84

Here is the Bionic Turtle video showing the basics of Regression

Here is the instructions for how to do the correlation coefficient on Stat Crunch