Linear regression involves fitting a straight line through the set of two or more data points accumulated in the statistical registers. Linear estimation uses this line to calculate an estimate of either x or y, based on the other.

estimates x for a given y value. The correlation coefficient (r) is returned in the y register.

estimates y for a given x value. The slope (m) of the line is returned in the y register. The y intercept of the line can be calculated by estimating y for x = 0.

Continuing the previous example,

Press to estimate the x value (50.36) for the given y value.

Press to display the correlation coefficient (0.97).

Press to estimate and display the y value (-5.34) for the given x value. This is the y-intercept of the fitted line.

Press to display the slope (0.34) of the fitted line.