WorksheetFunction.Forecast(Double, Object, Object) Method
Definition
Important
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Calculates, or predicts, a future value by using existing values. The predicted value is a y-value for a given x-value. The known values are existing x-values and y-values, and the new value is predicted by using linear regression. You can use this function to predict future sales, inventory requirements, or consumer trends.
public:
double Forecast(double Arg1, System::Object ^ Arg2, System::Object ^ Arg3);public double Forecast (double Arg1, object Arg2, object Arg3);Public Function Forecast (Arg1 As Double, Arg2 As Object, Arg3 As Object) As DoubleParameters
- Arg1
- Double
X - the data point for which you want to predict a value.
- Arg2
- Object
Known_y's - the dependent array or range of data.
- Arg3
- Object
Known_x's - the independent array or range of data.
Returns
Remarks
If x is nonnumeric, Forecast returns the #VALUE! error value.
If known_y's and known_x's are empty or contain a different number of data points, Forecast returns the #N/A error value.
If the variance of known_x's equals zero, then Forecast returns the #DIV/0! error value.
The equation for Forecast is a+bx, where:
Figure 1: Equation for the Forecast method
And:
Figure 2: Equation for the Forecast method
and where x and y are the sample means AVERAGE(known_x's) and AVERAGE(known y's).