HP 12C manual Statistics, Curve Fitting, Exponential Curve Fit

Statistics

Curve Fitting

Exponential Curve Fit

Using the function of the HP-12C, a least squares exponential curve

fit may be easily calculated according to the equation y=AeBx. The exponential curve fitting technique is often used to determine the growth rate of a variable such as a stock's value over time, when it is suspected that the performance is non-linear. The value for B is the decimal value of the continuous growth rate. For instance, assume after keying in several end-of-month price quotes for a particular stock it is determined that the value of B is 0.10. This means that over the measured growth period the stock has experienced a 10% continuous growth rate.

If B>0, you will have a growth curve. If B Examples of these are given below.

The procedure is as follows:

1.Press CLEAR .

2.For each input pair of values, key in the y-value and press , key in

the corresponding x-value and press .

3.After all data pairs are input, press to obtain the correlation coefficient (between ln y and x).

4.Press 1 0 to obtain A in the equation above.

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