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rsurvey

Create dummy variable with survey package

I want to transform a variable into a dummy using the survey package.

I have a complex sample design defined by:

library(survey)

prestratified_design <- svydesign(
  id = ~ PSU ,
  strata = ~ STRAT,
  data = data,
  weights = ~ weight ,
  nest = TRUE)

The dataset has a variable for education with 8 different categories:

# A tibble: 8 x 3
education     n  prop
  <int> <int> <dbl>
1     1  2919 20.8 
2     2  5551 39.5 
3     3   447  3.18
4     4   484  3.45
5     5  3719 26.5 
6     6    91  0.65
7     9   790  5.63
8    10    39  0.28

I want to create a dummy variable for categories 5 & 10 == 1 and others == 0.

I know that I have to use the update function, but I don't know how to use if in the survey package. I have tried:

prestratified_design <- update( 
  prestratified_design, 
    dummy_educ = as.numeric (education == 5 & education == 10)

but it obviously didn't work.

thank you!

Solution

  • You can create dummy variables in R via ifelse() if the number of categories is two. 

    df$dummy_educ = with(df, ifelse(education == 5 | education == 10, 1, 0))

    If the categories are more, you can use dplyr::case_when(), and if you are creating dummies from factor variable model.matrix() is fast and the best.