Casio fx-CG20 kLinear Regression Graph, kGraphing Statistical Calculation Results, kDisplaying Regression Calculation Results, MSe, y = ax + b, y = a + bx

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kDisplaying Regression Calculation Results

Whenever you perform a regression calculation, the regression formula parameter (such as a and b in the linear regression y = ax + b) calculation results appear on the display. The regression formula parameter calculation results also appear as soon as you press 1(CALC) and then a function key to select a regression type, while a graph is on the display.

The following parameters will also appear on the regression calculation result screen.

r ..............	correlation coefficient (linear regression, logarithmic regression, exponential
	regression, and power regression only)
r2 .............	coefficient of determination (except for Med-Med, sinusoidal regression, and
	logistic regression)
MSe.........	mean square error (except for Med-Med)

kGraphing Statistical Calculation Results

While the parameter calculation result is on the display, you can graph the displayed regression formula by pressing 6(DRAW).

kLinear Regression Graph

Linear regression uses the method of least squares to plot a straight line that passes close to as many data points as possible, and returns values for the slope and y-intercept (y-coordinate when x = 0) of the line.

The graphic representation of this relationship is a linear regression graph.

1(CALC)2(X)

1(ax+b) or 2(a+bx)

6(DRAW)

The following is the linear regression model formula.

y = ax + b

a............. regression coefficient (slope)

b............. regression constant term (y-intercept)

y = a + bx

a............. regression constant term (y-intercept)

b............. regression coefficient (slope)