Answers to questions about our graphs of left-right ideology of voters, congressmembers, and senators

July 23rd, 2008, by Andrew

After we posted our graphs from chapter 8 (see below entry), we got a few questions and comments that seem worth responding to:

1. What evidence did we use to estimate ideology of voters and congressmembers?

House members and senators’ positions are estimated based on their votes in Congress. Voters’ positions are estimated based on some survey questions where people were asked their views on a number of issues that had also been voted on in Congress.

2. Political ideology is not just left-right; it’s multidimensional.

True. Studies have found that legislators’ positions can be captured pretty well on a single left-right dimension, but voters are much more diverse in their views. Basically, what Joe and Michael are doing is placing voters on the left-right scale that is determined by legislative votes.

3. Commenter Ctate writes, “The graphs suggest that there are members of Congress — perhaps several of them — who are noticeably more liberal than any voters. Living as I do in Berkeley, I [Ctate] find it pretty unlikely that there are multiple legislators in office who are MORE liberal than my local community.”

The distributions are scaled to be the same size. So the question is whether in a random sample of 435 Americans, you’d expect to see anyone further to the left than the leftmost congressmember. The answer to that appears to be no.

4. But, still, are congressmembers really more extreme than voters?

Maybe, maybe not. The ideologies estimated by Joe and Michael (and graphed in our book) are scaled based on actual votes. So if your far-left or far-right friends have extreme views on issues that don’t come up in Congress, they won’t show up in this analysis.

Summary

The measurement issues here are real. How “left” or “right” you are depends on what questions you are asked. I think Joe and Michael did a good job (which is why we got graphs from them to use in our book), and there’s room for more to be done.

Similar Posts:

• Left-right ideology of voters, congressmembers, and senators
• Does America remain a center-right nation?
• Confusion about the changing positions of political parties in the U.S.
• Evidence that the state of the economy is crucial to voters
• The increasing importance of moral issues in American politics

Entry Filed under: Ideology