df1 {sure}

Simulated Quadratic Data

Description

Data simulated from a probit model with a quadratic trend. The data are described in Example 2 of Liu and Zhang (2017).

Usage

data(df1)

Format

A data frame with 2000 rows and 2 variables.

• y The response variable; an ordered factor.

• x The predictor variable.

References

Liu, Dungang and Zhang, Heping. Residuals and Diagnostics for Ordinal Regression Models: A Surrogate Approach. Journal of the American Statistical Association (accepted).

Examples

head(df1)