105^th congress

To see the fit statistics for the 105^th Congress click here.

For an explanation of the differences between the types of NOMINATE data please read this text file.

Format of W-NOMINATE scores

105th House W-NOMINATE Scores (Text File -- Updated, 23 February 2001)
105th Senate W-NOMINATE Scores (Text File -- Updated, 23 February 2001)
NOMINATE scores for other Congresses can be found on the Nominate Data download page.

Below is a histogram of the 105^th House. There is almost no overlap between the two parties. Morella of Maryland is the left-most Republican and she only has 4 Democrats -- Taylor of Mississippi, Goode of Virginia, Traficant of Ohio, and Hall of Texas -- to her right.

Below is a histogram of the roll call cutpoints for the 105^th House. Similar to the 104^th House (see below), the distribution of cutpoints is skewed to the left indicating that on many roll calls the Republicans were joined by substantial numbers of Democrats. However, unlike the 104^th House, there are now substantial numbers of cutpoints within the Republican party (although not as many as within the Democratic party) indicating that many moderate Republicans voted with the Democrats on many roll calls.

Below is a histogram of the 104^th House. Note that the distribution of cutpoints is skewed to the left reflecting the fact that the Republicans in the 104^th had the support of substantial numbers of moderate Democrats on many roll calls (including many on the Contract With America).

Below is a graph of the percent correct classifications from W-NOMINATE of the House of Representatives since World War II. Houses 103-105 are the best fitting since near the turn of the 20^th Century.

Below is a graph of the percent gain in classification due to the second dimension. The second dimension, which was improving classification by 5 percent or more in the late 1950s, is now inconsequential.

The next six figures show the first and second dimension means for the political parties in the House and Senate over the 1937 to 1998 period (75^th Congress through the 105^th Congress). These are W-NOMINATE coordinates adjusted so that the House and Senate coordinates are comparable. (See Recovering a Basic Space From a Set of Issue Scales for an explantion of how these coordinates were produced.)

The two chambers are very similar in their patterns over time. In the latter part of the New Deal voting on minimum wages (the Fair Labor Standards Act) opened up a split between the northern and southern wings of the Democratic party. During World War II, voting on issues related to the right of Blacks to vote in federal elections exacerbated the split. This split manifested itself as a second basic dimension in Congressional voting that largely captured voting on Civil Rights related issues. However, the split within the Democratic party also resulted in the Southern Democrats becoming more conservative on the first basic left-right/liberal-conservative dimension. (See Congress: A Political-Economic History of Roll Call Voting, Chapter 5 and Income Redistribution and the Realignment of American Politics (joint with Nolan McCarty, 1997, AEI Press) for an explanation).

Southern Democrats move to the right in both chambers on the first (liberal-conservative) dimension until just after the Civil Rights era of the mid to late 1960s and then begin moving back to the left during the 1970s and 1980s. Republicans shift to the left from the late 1940s and then reverse course after the Civil Rights era. Republicans in both chambers have been moving to the right since the late 1970s.

The gap between the Northern and Southern Democrats on the second dimension begins to close after the passage of the Civil Rights legislation in the 1960s. By the late 1980s, as shown by the classification graphs above, the gap had largely disappeared and was no longer of great importance.

Note that, because each member is assumed to have the same position throughout his or her career, these shifts in the various party means are due to replacement not conversion. The correlation between the chamber means on the first dimension is .89 (see fifth graph) and the second dimension .97 indicating that whatever forces are at work in American politics tend to work on both chambers equally, regardless their very different constituencies, terms, and internal rules and procedures. The corresponding correlations for Republicans, Northern Democrats, and Southern Democrats for the first dimension are .75, .82, and .74, respectively; and for the second dimension they are .86, .87, and .90 respectively.