Transportation to campus — transport • vasicekreg

Data from a stratified sample of 60 respondents concerning their mode of transportation to campus. The sampling design oversampled respondents who sometimes traveled to campus by bicycle.

Format

A data frame with 60 observations and 7 variables:

ntrips: Number of trips to campus during the preceding four weeks.
nbiked: Number of those trips made by bicycle.
status: Respondent's institutional status: faculty, staff, or student.
gender: Respondent's gender, recorded as "F" or "M".
parking: Duration of the parking permit, in months.
distance: Distance to campus. The source documentation does not specify the measurement unit.
propbiked: Proportion of trips to campus made by bicycle, calculated as nbiked / ntrips.

Source

Korosteleva, O. (2019). Advanced Regression Models with SAS and R. Boca Raton, FL: CRC Press.

https://github.com/AndrMenezes/uwquantreg

Details

The data originate from a consulting study reported by Korosteleva (2019). Menezes, Mazucheli, and Bourguignon (2021) analyzed them using an inflated unit-Weibull quantile regression model. The object distributed here retains the variable names and values supplied by the uwquantreg package.

References

Menezes, A. F. B., Mazucheli, J. and Bourguignon, M. (2021). A parametric quantile regression approach for modeling zero- or one-inflated double bounded data. Biometrical Journal, 63(4), 841–858. doi:10.1002/bimj.202000126

Menezes, A. F. B. (2026). uwquantreg: unit-Weibull quantile regression. R package version 0.1.0. https://github.com/AndrMenezes/uwquantreg

Examples

data("transport", package = "vasicekreg")
str(transport)
#> 'data.frame':	60 obs. of  7 variables:
#>  $ ntrips   : int  26 13 17 15 17 20 17 14 26 8 ...
#>  $ nbiked   : int  6 0 0 0 0 13 0 0 7 5 ...
#>  $ status   : chr  "student" "faculty" "faculty" "faculty" ...
#>  $ gender   : chr  "F" "M" "M" "M" ...
#>  $ parking  : int  6 9 9 9 6 6 9 9 6 12 ...
#>  $ distance : int  7 15 31 9 34 3 17 10 3 3 ...
#>  $ propbiked: num  0.231 0 0 0 0 ...
with(transport, all.equal(propbiked, nbiked / ntrips))
#> [1] TRUE