JULY 2010 
  Click here for the Web version of the current issue  

MiC Quality


Past Issues
April 2010
January 2010
July 2009
April 2009

December 2008

October 2008
June 2008
April 2008
February 2008
December 2007
October 2007
August 2007
June 2007
April 2007
February 2007



In Focus: Response Surface Methods

In this issue:

To unsubscribe please use the contact form and select "Unsubscribe from Updates".

:: Specials

We hope you are enjoying your holidays and to help you gently get back to work we are offering 4 weeks extra of access time if you enroll before or on August 23, 2010

:: Holiday Special: +4 WEEKS

For ALL Enrollments
QUOTE Promotional Code HS4

Holiday Special expires August 23, 2010
:: Response Surface Methods

Response surface methods are types of Experimental Design that investigate the curvature of the response surface. They achieve this by using a quadratic regression equation rather than the linear form of the regression equation used in factorial designs.

When the response surface is approximated by a linear equation the maximum and minimum values always occur at a corner point. Thus it is not possible to use the regression equation to optimize the process if the true maximum or minimum lies within the interior of the response surface.

There are various types of response surface design including the Central Composite (CCD) and Box Behnken designs. CCD is a type of response surface design that has points at:

  • the center
  • the corner points
  • axial points at 'a ' from the center

The design is usually rotatable, if the correct value of 'a' is selected.

A Box Behnken design is a type of response surface design that has points at:

  • the center
  • the midpoint of each side

There are no corner points. The design is spherical, all the points (except the center point) lie on a sphere of radius SQRT2.

For more information follow the link for Response Surface Methods in MiC Quality Six Sigma Glossary.

:: Six Sigma Primer
:: Statistical Process Control (SPC), Advanced Statistical Process Control
:: Design of Experiments (DOE), Advanced Design Of Experiments
:: Primer in Statistics, Advanced Statistics
:: Measurement Systems Analysis (MSA)/ Gage R&R
:: FREE Excel Primer
:: FREE Sample Module "Introduction to Statistics"
FREE Statistics Reference Booklet
FREE Six Sigma Summary Booklet
DOWNLOAD Brochure for All Courses


500+ terms Six Sigma Glossary
(includes all terms in the ASQ SSBB Six Sigma Black Belt Body of Knowledge)


Sigma Calculator


Book Reviews

:: Reference Tables
:: Next Update

The next update will be in October 2010.