6-3-8

Calculating and Graphing Paired-Variable Statistical Data

kLogarithmic Regression Graph

Logarithmic regression expresses y as a logarithmic function of x. The standard logarithmic regression formula is y = a + b × In x, so if we say that X = In x, the formula corresponds to linear regression formula y = a + bX.

1(CALC)6(g)2(Log)

6(DRAW)

The following is the logarithmic regression model formula.

y = a + b·ln x

a...............

regression constant term

b...............

regression coefficient

r...............

correlation coefficient

r2 .............

coefficient of determination

MSe ........

mean square error

kExponential Regression Graph

Exponential regression expresses y as a proportion of the exponential function of x. The standard exponential regression formula is y = a × ebx, so if we take the logarithms of both sides we get In y = In a + bx. Next, if we say Y = In y, and A = In a, the formula corresponds to linear regression formula Y = A + bx.

1(CALC)6(g)3(Exp)

6(DRAW)

The following is the exponential regression model formula.

y = a·ebx

a...............

regression coefficient

b...............

regression constant term

r...............

correlation coefficient

r2 .............

coefficient of determination

MSe ........

mean square error

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