Which methods are used for analysis of Residuals? (Raja, location unknown)

Another great question Raja! There are several ways that one might analyze residuals and the one that an analyst chooses is depended on their purpose/goal for analyzing the them. For example, if someone is testing whether the variance of their residuals are equal across levels of the predicted value of their model's DV ( an assumption of regression), one would use a scatterplot, placing the predicted value of their DV on the x-axis and the residual scores from the regression model on the y-axis.

NOTE: most statistical software packages will allow you to save both the predicted scores and residual scores of a regression model (in SPSS, simply place a checkmark in the desired boxes in the "save" dialogue of the "regression" analysis).

Conversely, if the residuals are being analyzed in an effort to control for confounds, the residuals of one regression model (a model with the variable/variables that are to be controlled as predictors) might be used as the DV in another model (a model that would feature your target variable of interest as the predictor).

In yet another analysis (of multivariate normality; also an assumption of regression), residual scores may be examined with a histogram to determine if their distribution is "normal."

I hope that is helpful!