OLS is just a special case of WLS, with all the weights equal. For cross-sectional surveys I find it inexplicable that OLS is generally the default, when it is often obvious from the data that assuming equal weights is very far from true. A graphical residual analysis will show this.
Here are some ways to estimate heteroscedasticity:
The sigmas are the standard deviations of the random factors of the estimated residuals. An asterisk represents a WLS approximation, employing notation used by G.S. Maddala in econometrics texts.
Note that above papers concentrated on estimating totals from finite populations, but had to also look at individual predictions for cross-sectional surveys. I assume you are looking at individual predictions. For SAS PROC REG, regression weights are entered as "w," and the estimated standard errors of the prediction errors are output as STDI. I assume other software has similar features.
Cheers - Jim
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