Casio fx-CG20 kLogarithmic Regression Graph, kExponential Regression Graph, y = a·bx, y = a·ebx

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

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)

1(aebx) or 2(abx)

6(DRAW)

The following is the exponential regression model formula.

y = a·ebx

a..............	regression coefficient
b..............	regression constant term
y = a·bx
a..............	regression constant term
b..............	regression coefficient

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