Data simulated from a probit model with heteroscedasticity. The data are described in Example 4 of Liu and Zhang (2017).
data(df2)
A data frame with 2000 rows and 2 variables.
x The predictor variable.
y The response variable; an ordered factor.
Liu, Dungang and Zhang, Heping. Residuals and Diagnostics for Ordinal Regression Models: A Surrogate Approach. Journal of the American Statistical Association (accepted).
head(df2)#> y x #> 1 3 4.275290 #> 2 4 4.019805 #> 3 3 3.756488 #> 4 3 5.321489 #> 5 3 4.317357 #> 6 3 2.115682