Library: | tware |
See also: | twrandomsample twpvalue twnormalize tw1d twlinreg twclt |
Quantlet: | twpearson | |
Description: | the teachware quantlet twpearson gives a visual demonstration of the form of the Pearson correlation coefficient. In particular, it shows why the product moment gives a measure of "dependence", and why it is essential to "normalize", i.e. to subtract means, and divide by standard deviations, to preserve that property. |
Usage: | twpearson({x}) | |
Input: | ||
x | matrix (n x 2) with user defined data |
; load teachware library library("tware") ; predefine matrix x = normal(100,2) ; call twpearson teachware quantlet twpearson(x)
a two window port display with the scatterplot of the matrix x in the upper port and the values of the product moments in the lower (text) port.