How do you perform a white test?
How do you perform a white test?
Follow these five steps to perform a White test:
- Estimate your model using OLS:
- Obtain the predicted Y values after estimating your model.
- Estimate the model using OLS:
- Retain the R-squared value from this regression:
- Calculate the F-statistic or the chi-squared statistic:
What is the special case of the white test?
What is the White Test? White’s test is used to test for heteroscedastic (“differently dispersed”) errors in regression analysis. It is a special case of the (simpler) Breusch-Pagan test. A graph showing heteroscedasticity; the White test is used to identify heteroscedastic errors in regression analysis.
How would you estimate the model correcting for heteroskedasticity?
Correcting for Heteroscedasticity One way to correct for heteroscedasticity is to compute the weighted least squares (WLS) estimator using an hypothesized specification for the variance. Often this specification is one of the regressors or its square.
How do you perform a White test in Excel?
Open the XLSTAT menu and click on Time / Tests for heteroscedasticity. Select the Residuals(Sugar) column in the Residuals box, and the Age column in the explanatory variables box. Check the White test checkbox and launch the analysis by clicking on the OK button.
How do you deal with Heteroskedasticity?
How to Fix Heteroscedasticity
- Transform the dependent variable. One way to fix heteroscedasticity is to transform the dependent variable in some way.
- Redefine the dependent variable. Another way to fix heteroscedasticity is to redefine the dependent variable.
- Use weighted regression.
How do you deal with heteroskedasticity?
What causes heteroskedasticity?
Heteroscedasticity is mainly due to the presence of outlier in the data. Outlier in Heteroscedasticity means that the observations that are either small or large with respect to the other observations are present in the sample. Heteroscedasticity is also caused due to omission of variables from the model.
How do you remove heteroscedasticity in regression?
What is the White statistic?
In statistics, the White test is a statistical test that establishes whether the variance of the errors in a regression model is constant: that is for homoskedasticity. If cross products are introduced in the model, then it is a test of both heteroskedasticity and specification bias.