Computes scores based on the Vanilla method suggested by Gabel & Huber. A factor analysis identifies the dominant dimension in the data. Factor scores using the regression method are then considered as party positions on this dominant dimension.
vanilla(
data,
vars = grep("per\\d{3}$", names(data), value = TRUE),
invert = FALSE
)
A data.frame with cases to be scaled, variables named "per..."
variable names that should be used for the scaling (usually the variables per101,per102,...)
invert scores (to change the direction of the dimension to facilitate comparison with other indices) (default is FALSE)
Gabel, M. J., & Huber, J. D. (2000). Putting Parties in Their Place: Inferring Party Left-Right Ideological Positions from Party Manifestos Data. American Journal of Political Science, 44(1), 94-103.