Below we use data from the Center for Responsive Politics on the estimated 2010 personal wealth of members of Congress and members’ first dimension (ideological) DW-NOMINATE Common Space scores to plot the relationship between ideology and personal wealth for present members of Congress.
More technically, we take the log of members’ estimated wealth, as is customary with variables like income or campaign spending because changes are more influential when values are small than when they are large. For example, accumulating an extra $50,000 has a far larger effect on a a political scientist than it would on Bill Gates. Logged scales adjust for this distortion.
In addition, we plot a lowess smoother to look for evidence of a systematic relationship between ideological position and level of personal wealth (for example, if conservative members are wealthier than liberal ones, or if extremists on both sides are wealthier than their moderate counterparts). We find no ideological patterns in the data: average wealth remains steady as we move along the liberal-conservative scale. Anecdotally, this conclusion is supported by a quick examination of the six wealthiest members of Congress in 2010, a list which spans ideological and partisan divides in the 112th Congress: Representatives Darrell Issa (R-CA) [0.538], Michael McCaul (R-TX) [0.456], Jane Harman (D-CA) [-0.289], and Nancy Pelosi (D-CA) [-0.544]; and Senators Kerb Kohl (D-WI) [-0.284] and John Kerry (D-MA) [-0.386].
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