INTERCEPT function

This topic describes the formula syntax and usage of the INTERCEPT function in the Data Quality Execute Formula transform.

Description

Returns the intercept of the linear regression line. The intercept point is based on a best-fit regression line plotted through the known x-values and known y-values. Use the INTERCEPT function when you want to determine the value of the dependent variable when the independent variable is 0 (zero).

Syntax

INTERCEPT(known_y's, known_x's)

The INTERCEPT function syntax has the following arguments:

  • known_y's Required. The dependent set of observations or data.
  • known_x's Required. The independent set of observations or data.

Notes

  • For a linear function expressed in slope-intercept form as f(x) = a + bx the constant term a is the y-coordinate of the y-intercept.
  • The equation for the intercept of the regression line is a = bx, where the slope b is calculated as:

    where x and y are the sample means AVERAGE(known_x's) and AVERAGE(known_y's).

Example

Formula: Y-intercept = INTERCEPT([Y1]:[Y5],[X1]:[X5])
Table 1. Data
X1 X2 X3 X4 X5 Y1 Y2 Y3 Y4 Y5 Y-intercept
0 1 2 3 4 8 7 6 5 4 8
0 1 2 3 4 2 3 4 5 6 2