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Statistics Programs

Curve Fitting

This program can be used to fit one of four models of equations to your data. These models are the straight line, the logarithmic curve, the exponential curve and the power curve. The program accepts two or more (x, y) data pairs and then calculates the correlation coefficient, r, and the two regression coefficients, m and b. The program includes a routine to calculate the estimates xˆ and yˆ . (For definitions of these values, see "Linear Regression" in chapter 11.)

Samples of the curves and the relevant equations are shown below. The internal regression functions of the HP 33s are used to compute the regression coefficients.

Statistics Programs 16–1