Chapters:
1: Introduction
2: Simple example
3: Invocation
4: Finer Control
5: X-Y Plots
6: Contour Plots
7: Image Plots
8: Examples
9: Gri Commands
10: Programming
11: Environment
12: Emacs Mode
13: History
14: Installation
15: Gri Bugs
16: Test Suite
17: Gri in Press
18: Acknowledgments

Indices:
Concepts
Commands
Variables

### 9.3.34: ``regress`'

 ``` `regress {y vs x [linear]}|{x vs y [linear]}' ```

Perform linear regression of ``y`' as a function of ``x`' or ``x`' as a function of ``y`'.

• ``regress y vs x`' Linear regression of y vs x. Several quantities are reported and also saved into builtin variables. The intercept is defined as ``..coeff0..`', its 95 percent confidence limit is defined as ``..coeff0_sig..`'. Thus the confidence range is ``..coeff0..-..coeff0_sig..`' to ``..coeff0..+..coeff0_sig..`'. Similarly the slope and confidence limit are stored in ``..coeff1..`' and ``..coeff1_sig..`'

The squared correlation coefficient is stored in ``..R2..`'.

Historical note prior to version 2.1.15, a different meaning was attached to ``..coeff0_sig..`' and ``..coeff1_sig..`'; they used be defined as standard errors, without having been multiplied by the appropriate student-t coefficient.

• ``regress x vs y`' Linear regression of x vs y; for notation see above.

• ``regress y vs x linear`' Linear regression of y vs x; for notation see above.

• ``regress x vs y linear`' Linear regression of x vs y; for notation see above.