Data parameters can now be created with bivariate data.

$b=data((11,12)(15,19)(21,28)(13.2,19.4),(8,16))

Bivariate data is entered as separate data points, wrapped in parentheses, which are then (optionally) separated with your normal separator.

New RandBivariate Parameter

Often, the best way to create random bivariate is to use a randbivariate parameter.

$p=RandBivariate(lowx, highx, slope, intercept, targetr, number)

Generates number random bivariate data points with the x values ranging from lowx to highx. The data will approximately fit a linear regression line with the given slope and intercept with a correlation coefficient of approximately targetr.

If you want data with a negative correlation, you MUST enter a negative slope, NOT a negative targetr.

Statistical Commands

There are a number of new statistical commands that can operate on bivariate data parameters.

regslope($p) will return the slope of the line of best fit for the bivariate data.
regintercept($p) will return the intercept of the line of best fit for the bivariate data
regr($p) will return the correlation coefficient for the bivariate data

Other Commands

$b=data((11,12)(15,19)(21,28)(13.2,19.4),(8,16)) creates 5 data points, each with an x value and a y value.

$b[3] will return (21,28)
xvalue($b[3]) will return 21
yvalue($b[3]) will return 28