Documentation/How Tos/Calc: STEYX function
From Apache OpenOffice Wiki
STEYX
Fits a straight line to data using linear regression and returns the standard error of y values.
Syntax:
STEYX(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.
- STEYX in effect fits a straight line through these data points, using the linear regression method (least squares). It then returns the standard error of actual y values compared to y values on the straight line found.
- The equation of a straight line may be given as y = a + bx. The linear regression method calculates:
- and
- where y_{i} are the actual values and y_{i}' are the computed values on the line.
- Advanced topic:
- The parameters xvalues and yvalues are always evaluated as array formulas.
Example:
STEYX(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 approximately 0.51. The equation of the straight line found is very nearly y = 2x, and would be if B4 contained 6. The standard error is therefore quite small.