Bivariate statistics means statistics with two variables. Your TI-84 calculator can do the complete statistical analysis if you follow the simple steps described bellow.
Open the statistical lists:
STATEnter your data in lists L1 and L2 (e.g., you can enter weights in L1 and heights in L2).
If the lists are not empty maybe you'll want to clear these two lists before entering new values. You can do it using:
STATTo get the bivariate statistics use:
STATAfter pressing the ENTER button your calculator will display the results. Results include a lot of statistical parameters. The most important of them are:
x = the mean (average) of the variable xIf you want your statistical analysis to be done correctly your first step is turning on the diagnostic. To do it use the CATALOG button. Find DiagnosticOn and select it.
Then you can find the regression line (line of best fit). Use:
STATAfter pressing the ENTER button the calculator will display the results. Results include the parameters a and b which determine the regression line y = ax + b.
Besides, you'll see the correlation coefficient r (called also Pearson product-moment correlation coefficient). If you don't see the value of r you must have forgotten to select DiagnosticOn.
(*) StoreRegEQ means storing the regression line equation. If you select StoreRegEQ: Y1 then the equation will be stored as function Y1 and you can draw its graph. In order to get symbol Y1 here, press:
VARSAfter that you can draw the regression line – press GRAPH. However, probably you will not see the graph because it's not on the screen. Adjust the window settings (they must include all the values of your data).
For drawing the scatter graph you'll have to activate the statistical plots:
2ND STAT PLOTNow the scatter graph should appear on the screen. If you don't see it you must adjust the window settings (press WINDOW and select correct values for Xmin, Xmax, Ymin, Ymax, then press GRAPH again).
If you selected StoreRegEQ: Y1 (see above (*)) you'll see the regression line, too.