Statistics; Curve Fitting; Exponential Curve Fit - HP 12c Platinum Reference Manual

Curve Fitting

Exponential Curve Fit

Using the ° function of the HP 12C Platinum, a least squares exponential curve fit may
be easily calculated according to the equation y=Ae
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<0, you will have a decay curve.
Examples of these are given below.
GROWTH CURVE
(B>0)
Time
The procedure is as follows:
1. Press f CLEAR H .
2. For each input pair of values, key in the y-value and press g° , key in the
corresponding x-value and press _ .
3. After all data pairs are input, press gR~ to obtain the correlation coefficient
(between ln y and x).

Statistics

Bx
98
. The exponential curve fitting
DECAY CURVE
(B<0)
Time