### Validating a regression model

Passing checks 1 and 2 will ensure that the independent and dependent variable are related. If the model fit to the data were correct, the residuals would approximate the random errors that make the relationship between the explanatory variables and the response variable a statistical relationship. There are also a variety of statistical estimators based on correction to the degrees of freedom, standard errors, etc. If, for example, the out-of-sample mean squared error , also known as the mean squared prediction error , is substantially higher than the in-sample mean square error, this is a sign of deficiency in the model. Journals that are no longer published or that have been combined with another title. The resulting correlation between the predicted scores and the observed scores is an estimate of how well a regression equation calculated on all n subjects will work in the population. For example, if the current year is and a journal has a 5 year moving wall, articles from the year are available. Mutual information will very simply tell you if variable X is related to variable Y, and how much uncertainty is reduced in predicting Y if the uncertainty in knowing X is quantified. Terms Related to the Moving Wall Fixed walls: The use of mutual information for testing if two variables are related is highly effective in such cases. I correlated raw and predictd scores in another sample different from that with which the equation was built. I would see it if I correlated raw and predicted scores in the same sample, isn't it? The problem of heteroskedasticity can be checked for in any of several ways. Since each of the equations developed in the n-1 subjects is not independent of each other, there is going to be a slight bias tn the final estimate of how well the regression equation will work in the population from which you sample is drawn. I hope that reviewers and editors see it the same way: Therefore, if the residuals appear to behave randomly, it suggests that the model fits the data well. Papers also reflect shifts in attitudes about data analysis e. On the other hand, if non-random structure is evident in the residuals, it is a clear sign that the model fits the data poorly. Cross Validation with Small Samples: This includes an emphasis on new statistical approaches to screening, modeling, pattern characterization, and change detection that take advantage of massive computing capabilities. Highly non-linear relationships will result in simple regression models failing checks 1 through 3. This of course requires the assumption of normal distribution of all sample slopes that make up the population. In rare instances, a publisher has elected to have a "zero" moving wall, so their current issues are available in JSTOR shortly after publication. Thank you all for your help and suggestions. The issue for many business analytics problems is frequently knowing which technique best answers the questions posed. However this does not imply that the independent variable is the cause and the dependent is the effect. In such cases it may become necessary to resort to somewhat more advanced bivariate analysis methods.