topic Re: Error term and Residuals in Statistical Procedures

Error term and Residuals

RamKumar — Wed, 18 Feb 2015 10:34:19 GMT

What is the difference between error term and residuals in modeling?

Re: Error term and Residuals

PaigeMiller — Wed, 18 Feb 2015 14:34:43 GMT

An error term exists in the model. It is a mathematical construct.

The residual is the actual value of one data point (deviation from the value predicted by the model).

Re: Error term and Residuals

RamKumar — Wed, 18 Feb 2015 14:55:31 GMT

I understood residuals now.

How does an error term exists in the model? May I request you to give an simple example please.

Re: Error term and Residuals

PaigeMiller — Wed, 18 Feb 2015 16:12:46 GMT

A simple regression model looks like this

y = b0 + b1*X + e

e is the error term, b0 is the intercept and b1 is the slope

Re: Error term and Residuals

RamKumar — Wed, 18 Feb 2015 17:52:16 GMT

Thanks.

Where that 'e' comes from?

Re: Error term and Residuals

Reeza — Wed, 18 Feb 2015 18:08:15 GMT

FYI the Stats course for SAS is free via the SAS Analytics U homepage.

From wikipedia:

http://en.wikipedia.org/wiki/Regression_analysis

Theoretical Model with e :

Fitted model:

The residual, , is the difference between the value of the dependent variable predicted by the model, , and the true value of the dependent variable, .

Re: Error term and Residuals

SteveDenham — Wed, 18 Feb 2015 18:24:24 GMT

I would recommend reading some good introductory regression and linear modeling texts. You may find this one to be helpful:

Regression Modeling Strategies: With Applications to Linear Models, Logistic Regression, and Survival Analysis, by Frank Harrell, Jr.

Steve Denham