Bowens Model:

Preference of a voter for the public good is represented by MRS (Marginal rate of substitution of Public Goods for Money Income). It is negatively sloped and convex to the origin in the Figure.  Corresponding to the peak point of a Normal Curve

where Mean=Median = Mode,  [ (n+1)/2] preference curve passes through the point E which represents the Median Voter Preference and also coincides with the modal curve (the preference curve of most voters, Majority).