Computes the relative measure of party size as suggested by Giebler/Lacewell/Regel/Werner 2015.
mp_rmps(data, adapt_zeros = TRUE, ignore_na = TRUE, threshold_sum = 75)a numerical vector with vote shares
a boolean to switch on the conversion of zero values to 0.01 to avoid issues concerning division by zero
a boolean to switch on ignoring NA entries, otherwise having NA entries will lead to only NA values in the result
the threshold of the sum of all vote shares for allowing the calculation
a vector of rmps values
Hint: In a dataset with multiple elections the usage of the function might require to calculate the measure per election (eg. using group_by)
Giebler, Heiko, Onawa Promise Lacewell, Sven Regel and Annika Werner. 2015. Niedergang oder Wandel? Parteitypen und die Krise der repraesentativen Demokratie. In Steckt die Demokratie in der Krise?, ed. Wolfgang Merkel, 181-219. Wiesbaden: Springer VS.