Documentation/How Tos/Calc: INTERCEPT function

INTERCEPT

Fits a straight line to data using linear regression and returns its intercept on the y-axis.

Syntax:

INTERCEPT(yvalues; xvalues)

yvalues and xvalues are single row or column ranges specifying points in a set of data. yvalues and xvalues must be the same size.

INTERCEPT fits a straight line through these data points, using the linear regression method (least squares). It then returns the y value where that straight line crosses the y-axis.

The equation of a straight line may be given as y = a + bx. The linear regression method calculates:

and

.

a is the y-axis intercept returned by this function.

Advanced topic:

The parameters xvalues and yvalues are always evaluated as array formulas.

Example:

INTERCEPT(B2:B6; A2:A6)

where the x values in A2:A6 are 1, 2, 3, 4, 5 and the y values in B2:B6 are 2, 4, 7, 8, 10 returns 0.2. The equation of the straight line found is very nearly y = 2x (and would be if B4 contained 6) - thus the straight line very nearly (but not quite) goes through the origin.

See also:

FORECAST, SLOPE, STEY

Array formulas

Statistical functions