6-3-9

Calculating and Graphing Paired-Variable Statistical Data

k Power Regression Graph

Power regression expresses y as a proportion of the power of x. The standard power regression formula is y = a ⋅ xb, so if we take the logarithm of both sides we get In y = In a + b ⋅ In x. Next, if we say X = In x, Y = In y, and A = In a, the formula corresponds to linear regression formula Y = A + bX.

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6(DRAW)

The following is the power regression model formula.

y = a • xb

a............. regression coefficient

b............. regression power

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

correlation coefficient

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

coefficient of determination

MSe ........

mean square error

k Sinusoidal Regression Graph

Sinusoidal regression is best applied for cyclical data.

The following is the sinusoidal regression model formula.

y = a·sin(bx + c) + d

While the statistical data list is on the display, perform the following key operation.

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6(DRAW)

Make sure that the angle unit setting of the calculator is Rad (radians) when drawing a sinusoidal regression graph. The sinusoidal regression calculation is performed using radians, so the graph will cannot be drawn correctly if the angle unit setting is something else.

• Certain types of data may take a long time to calculate. This does not indicate malfunction.

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