Scaling Voters, Candidates, and Groups with Feeling Thermometers

Below we use Bakker and Poole’s Bayesian multidimensional scaling method to scale voters, candidates, and groups together using respondents’ feeling thermometer ratings. Specifically, the UGA module of the 2015 Cooperative Congressional Election Study asked 1,000 respondents to rate how warmly or coldly they felt about a series of candidates and groups (e.g., investment bankers, Muslims, Evangelical Christians, etc.).

Based on these thermometer ratings, we can jointly scale voters and these candidates/groups such that greater distances correspond to “colder” ratings and smaller distances correspond to “warmer” ratings. The main advantage of the Bakker-Poole method is that it avoids pushing candidates/groups too far to the edges of the space. That is, there are some voters to the left of Sanders and the right of Trump–as a general rule, candidates shouldn’t be the most extreme points in the space. As a technical matter, this is because Bakker-Poole MDS uses the log-normal distribution to model the thermometer ratings, which reflects the intuition that smaller distances should have smaller error variances.

The results are shown below. Because we are using a Bayesian approach, we can easily extract measures of uncertainty for the point locations (Jacoby and Armstrong have also developed a bootstrapping approach to estimate uncertainty intervals for MDS solutions). Accordingly, we also plot the 95% credible intervals for Donald Trump, Marco Rubio, Jeb Bush, Bernie Sanders, Hillary Clinton, and Pope Francis.

Several things stand out. First, there is a clear liberal-conservative division not only among candidates and partisans, but also social groups. There are two distinct clusters of Democratic and Republican candidates, voters, and groups.

That being said, there are also internal divisions within each of the party clusters. Both Clintons and President Obama are highest on the second dimension, while we find Sanders and several liberal groups lower on the second dimension. Socialists are placed the furthest left of all groups. On the Republican side, Trump and Jeb Bush anchor opposite ends of the second dimension. As we would expect, more Republicans have high second dimension scores (closer to Trump) than low second dimension scores (closer to Jeb Bush).

There is more uncertainty associated with the locations of the Republican candidates than with Hillary Clinton or Bernie Sanders. Hillary Clinton is also closer to the interior of the Democratic Party than Trump is to the interior of the Republican Party.

Click image to enlarge

The Politics of Firearms Control

The first serious effort by the federal government to control firearms was The National Firearms Act of 1934 (for a detailed summary, see Anthony Madonna’s summary of the legislative history of the 1934 NFA). The bill was passed on 18 June 1934. The Act taxed the sale of machine guns, sawed off shotguns or rifles, and silencers. The NFA was a response to the notorious gangsters and bank robbers of the era — for example, John Dillinger, Bonnie and Clyde, and Pretty Boy Floyd (all were shot dead by law enforcement officers in 1934). The plague of gangsters who robbed banks and then fled across state lines led to Congress passing The Federal Bank Robbery Act of 1934 on 14 May 1934. This made it a federal crime to rob any national bank or state member bank of the Federal Reserve. This act allowed the FBI aided by local law enforcement officials to pursue bank robbers across state lines. The bill was passed by both Chambers by voice vote.

The debate over the NFA prefigures some of the debate taking place today. The decision to tax and register machine guns seemed to implicitly assume that individuals had the right to own firearms under the second amendment. Certainly firearm ownership was relatively widespread in the 19th Century in rural areas of the United States and Congress made no effort to limit their ownership. The wording of the second amendment is hotly contested in the 5-4 District of Columbia et al. v Heller (2008) decision. The five justices in the majority held that individuals had the right to own a personal firearm whereas the four justices in the minority held that this right was linked to membership in a (State) militia. Needless to say, each side constructed their arguments around different interpretations of the Founders’ intent and early history of the Republic.

The next significant Act that regulated firearms was the Gun Control Act of 1968. It was a response to the murders of President John F. Kennedy (22 November 1963), Dr. Martin Luther King (4 April 1968), and Robert F. Kennedy (6 June 1968 — he was shot by Sirhan Sirhan on 5 June 1968). President Kennedy was murdered by Lee Harvey Oswald with a bolt action rifle. Dr. King was murdered by James Earl Ray with a bolt action rifle. And Robert Kennedy was murdered by Sirhan Sirhan with a 22 caliber pistol.

The 1968 Act finally banned mail order sales of rifles and shotguns and prohibiting most felons, drug users and people found mentally incompetent from buying guns. The key votes shown below were lopsided with majorities of both political parties supporting the law.

Click image to enlarge

Click image to enlarge

President Johnson, echoing some of the debate of the 1934 NFA, when he signed the 1968 Act stated: I asked for the national registration of all guns and the licensing of those who carry those guns. Clearly he felt that national registration and licensing was Constitutional and did not violate the second Amendment.

The next significant piece of legislation on firearms control was The Brady Handgun Violence Prevention Act passed by Congress in 1993 and backed by former President Ronald Reagan. The Brady Bill required that background checks be conducted on individuals before a firearm may be purchased from a federally licensed dealer, manufacturer or importer with a five day waiting period before the purchase could be completed. The National Rifle Association opposed the law and managed to get a provision inserted that mandated the National Instant Criminal Background Check System be put into effect by 1998. This system is still in use.

The Brady Bill split both political parties internally. In the House the old (and dying) Conservative Coalition was against the Act but it still passed by a comfortable margin.

Click image to enlarge

Click image to enlarge

Almost at the same time as the Brady Act was being considered a ban on Assault Weapons was also being debated. The attention to Assault Weapons (basically, military style semi-automatic rifles and pistols) began with a 1989 school yard shooting in Stockton, California and later a 1993 shooting in San Francisco, California. Both shooters appeared to have been insane and committed suicide rather than be captured. The Stockton shooting led President George H.W. Bush to ban all imports of Assault Weapons into the United States in 1989.

The votes on the Assault Weapons ban were closer than those for the Brady Bill. Once again, the votes split both political parties internally with the vote in the House being very close. In a preview of what was to come the Senate Democrats were more united in favor of Gun Control than House Democrats. The political parties were beginning to move to a polarized position on the issue of Gun Control.

Click image to enlarge

Click image to enlarge

Next up was a push by firearms supporters for the protection of gun makers from civil lawsuits over the use of their guns in crimes. This was the Protection of Lawful Commerce in Arms Act. The basic idea was to protect manufacturers from being sued because someone criminally used a firearm. As Senator Sanders (I-VT) put it during the 2016 Democratic Presidential Primary Campaign: “If somebody has a gun and it falls into the hands of a murderer and the murderer kills somebody with a gun, do you hold the gun manufacturer responsible? Not any more than you would hold a hammer company responsible if somebody beats somebody over the head with a hammer.”

The votes are similar to the Assault Weapons Ban only now the Republican Party is now almost completely pro-firearm while the Democratic Party is split. The high PRE values indicate that the issue is become more divisive and set the stage for the battles during the Obama Administration.

Click image to enlarge

Click image to enlarge

During the Administration of President Obama a number of high profile shootings has raised the salience of gun control to a very high level. These shootings include the mass casualty shooting in a movie theater in Aurora, Colorado, on 20 July 2012 (12 dead, the shooter, James Holmes, was later ruled to be insane), the Sandy Hook Elementary School shooting in Newtown, Connecticut on 14 December 2012 (27 dead and the shooter, Adam Lanza, committed suicide [he had murdered his mother before he went to the school]), and most recently, the Pulse Nightclub shooting in Orlando, Florida on 12 June 2016 (49 dead and the shooter, Omar Mateen, was shot dead by police).

In all three shootings semi-automatic weapons were legally obtained (in the Sandy Hook case, obtained by his Mother) and used by the shooters. In the cases of James Holmes and Omar Mateen a better background check system should have prevented them from buying the weapons they used in the shootings. Holmes had been seen by a Psychiatrist at the University of Coloradoand evidently “fantasized about killing a lot of people.” Mateen was known to the FBI but this evidently was not enough to flag him during a firearms background check. Consequently, recent legislative action in Congress has focussed on beefing up the background check system.

So far action has only occurred in the Senate. On Monday, 20 June the Senate voted on the Republican version of a beefed up background check system that would encourage states to share mental health records as part of the system. The Senate also voted on the Democrat version that would require a background check for most sales or transfers of guns.

Unfortunately, from 1934 when firearms control was unanimously supported by both parties, the issue has now fallen into the vortex of partisan polarization. Almost all sensible people agree that, at the least, the background check system should be considerably expanded to include persons on the “no fly list” and include records on individuals who are clearly insane. The devil is in the details. In the past when there were a substantial number of moderates in both parties this would be an easy question to resolve. Some sort of semi-judicial system should be set up to decide if someone was unfairly denied the right to purchase a firearm. But 2016 is an election year and gun control has become a deeply partisan issue. It is possible that there may be a compromise but that seems to be a long shot as things stand at the moment.

Click image to enlarge

Click image to enlarge

Ideological Positions of Clinton and Sanders Voters

In this post, we look at the ideological positions of Clinton and Sanders supporters among non-Republican respondents to the pilot study of the 2016 American National Election Study. We look at both the raw and weighted responses (in which survey weights are applied to approximate the demographic makeup of the population).

Even with weighting applied, non-Republican respondents who support Sanders in the Democratic primary are to the left of Clinton on most issues, especially the issue priority questions (that is, Sanders voters are more likely to say that income inequality and the environment are among their top issues). These issue salience measures have been shown to be influential in voters’ evaluations of candidates.

In the last two graphs, we also use the Aldrich-McKelvey scaling procedure (detailed in an recent post) to get a handle on the ideological positions of non-Republican Clinton and Sanders supporters. This method uses respondents’ placements of themselves and parties/candidates on the liberal-conservative scale to produce ideal point estimates that adjust for biases (or differential item-functioning) in the way respondents use these scales. Again, both with and without weighting, non-Republican Sanders supporters seem to be somewhat more liberal than Clinton supporters. These differences between the two camps aren’t massive, but may nonetheless be signaling something of an ideological split in the Democratic party.

Click images to enlarge





Issue Priorities, Partisanship, and Crossover Voting in 2016

In this post, we look at the relationship between issue salience, candidate support, and partisanship vary by candidate support using data from the pilot study of the 2016 American National Election Study. This is part of a larger project that examines how different types of Democrats and Republicans vary in their issue priorities. In addition, issue salience may help to get a better handle on crossover voting (Democrats voting for Trump/Republicans voting for Clinton) in the 2016 election.

Below, we plot the percentages of each candidate’s supporters (whether they answered Clinton, Trump, or other/not vote in the general election matchup question) naming the given issue as one of their top four most personally important issues.

We show just Democrats and independents in the first plot, and isolate Republicans and independents in the second plot. We include independents in both groups because the sample sizes for Trump Democrats and (especially) Clinton Republicans is negligible (there are 24 Democrats who support Trump and 4 Republicans who support Clinton). Combining independents with both groups seems to reinforce the patterns when isolating respondents by partisanship (we provide these plots at the bottom of the post), but provides more leverage for the analysis.

The results indicate that crossover voters are indeed more likely to name issues “owned” by the opposite party as important. Issues like immigration, the national debt, and terrorism are more salient to respondents (including Democrats/independents) who support Trump. Conversely, the issues of environmental protection, health care, and income inequality are more salient to Clinton supporters (including Republicans/independents). It doesn’t appear that issue salience is of much help in explaining which respondents say they would vote for another candidate or not vote in a Clinton/Trump matchup—these respondents simply aren’t distinctive in their issue priorities. We thought that the other/not vote Republicans would be more likely to prioritize social issues (abortion and morality), but this doesn’t appear to be the case.

Certainly, some of this is a projection effect, but, especially in a year in which ideology plays such a murky role, issue salience can pick up the slack in modeling vote choice and crossover voting.

Click images to enlarge



Below are show separate plots for Democratic, independent, and Republican respondents. The general findings are consistent with the above graphs, but (especially when it comes to Republicans who support Clinton), the sample sizes are quite small.

Click images to enlarge



Ideological Perceptions of the 2016 Presidential Candidates

Below, we use Aldrich-McKelvey scaling (see here and here for background) to analyze voters’ ideological perceptions of the 2016 presidential candidates and other political figures. The 2016 pilot study of the American National Election Study asked respondents to place themselves and each of these figures on a seven-point ideological scale ranging from “extremely liberal” to “extremely conservative.” The Aldrich-McKelvey scaling procedure allows us to recover bias-corrected estimates of the respondents and candidates on the underlying ideological dimension.

The estimated scores (plotted below) show that three Democratic figures (the Democratic Party, President Obama, and Secretary Clinton) are ideologically clustered together. Clinton is a bit closer to the center than the other two, but not by much. On the other hand, there is considerable heterogeneity in ideological perceptions of the four Republican stimuli: Senator Rubio, Donald Trump, the Republican Party, Senator Cruz. It’s probably not surprising that Rubio is perceived to be the most moderate and Cruz is perceived to be the most conservative of the four.

What is noteworthy is that Trump is placed at nearly the same spot as Rubio. Trump, however, has the the greatest amount of uncertainty associated with his ideological score (as a technical note, we estimate 95% confidence intervals for the Aldrich-McKelvey scores using 1,000 bootstrap replications, as described in Chapter 3 of our book on estimating spatial models).

This is equivalent to saying that respondents differ the most in where they place Trump on the ideological scale. The width of Trump’s confidence interval is about twice that of Clinton’s, for instance. This uncertainty could be a factor in the 2016 race, as some political science research suggests that voters reward candidate ambiguity (see also here).

Click image to enlarge


We wondered if voter uncertainty about Trump’s ideological position was being driven by a divide among self-identified conservative respondents; that is, between those who embrace Trump and believe he’s a conservative, and those (e.g., #NeverTrumpers) who doubt Trump’s conservative credentials. To look into this possibility, we plotted the mean placements of Trump and Clinton by respondents’ ideological self-identifications. “1” indicates extremely liberal, “2” indicates liberal, and so on until “7” for extremely conservative. Respondents are sorted in this way on on the vertical axis of the graph below.

For each ideological category of respondents, mean placements of Clinton and Trump are shown along the same seven-point liberal-conservative scale on the horizontal axis. For example, the most conservative respondents (self-identified “7”‘s or extremely conservative) place Clinton furthest to the left. The gray bars represent variation in the corresponding group’s ideological placements of Clinton and Trump.

Interesting, across the ideological categories, respondents are pretty evenly uncertain about Trump’s position on the liberal-conservative scale. On the whole, self-identified conservatives do view Trump as somewhat more moderate than do self-identified liberals (evidence of what is known as interpersonal incomparability or differential item-functioning). But, it is self-identified moderates who place Trump closest to the center (and have the least variation in their Trump placements).

Click image to enlarge


The Whigs and The Republicans

The last time a major Political Party broke apart was in the early 1850s when the Whig Party collapsed because of the Compromise of 1850. The Compromise was an effort by Party leaders to settle the various controversies between North and South with a classic set of tradeoffs. The Compromise was made possible by the death of President Zachary Taylor on 9 July 1850.

The Compromise of 1850 was consisted of five separate bills. The first was to organize the Territory of New Mexico which was part of the Mexican Cession of 1848 that Mexico ceded to the U.S. in the Treaty of Guadalupe Hidalgo.  Texas claimed most of what is now New Mexico so the bill to organize the New Mexico Territory consisted of a payment to Texas for the land east of the Rio Grande River up to the modern border of Texas (this was approved by the Texas State Legislature).  The Federal Government also assumed Texas’ debt resulting from its War of Independence from Mexico.  In addition, slavery would be decided by the people of the Territory by Popular Sovereignty.  This was a rejection of the Wilmot Proviso that would have banned slavery in any territory acquired from Mexico in the Mexican War. It was proposed by David Wilmot (D-PA) in August of 1846. It passed in the House in 1846 and 1847 but was defeated in the Senate so it never became law. Although it was never passed by Congress it was very important to the Northern Anti-Slavery forces.

Below is the House vote on organizing the New Mexico Territory.  The roll call split Southerners with many Southern Democrats opposing the bill.  They opposed the reduction in the size of the slave state of Texas.  However, most Southerners voted for the bill because they felt the tradeoff of reducing Texas was worth being rid of the Wilmot Proviso and the chance of organizing New Mexico as a Slave state.

In Contrast to the Southerners, most Northerners voted against the bill but enough Northerners voted with the Southerners to squeeze the bill through the House.

Click image to enlarge

Second up was the admission of California as a Free state. This was an easy bill to pass simply because of the massive amount of gold flowing into the economy from California.  The opposition was mainly from Southern Democrats.

Click image to enlarge

The Utah Territory was organized on the same terms of New Mexico.

Click image to enlarge

The most controversial part of the Compromise for Northerners was the Fugitive Slave Law.  However, as shown below, it passed by a comfortable margin largely along sectional lines with significant Northern Democratic support but with substantial Northern Whig opposition.

Click image to enlarge

Finally, the Slave Trade but not Slavery itself was abolished in the District of Columbia.

Click image to enlarge

The Fugitive Slave Law roiled the Northern Whigs during 1851-52 and that marked the beginning of the unraveling of the Whig Party. The Party structure of the 32nd Congress (1851-52)  simply collapsed as documented by Joel Silbey’s
The Shrine of Party: Congressional Voting Behavior, 1841-1852 and Poole and Rosenthal (1997) chapters 3 and 5. This is shown in the roll call vote below which reaffirmed the support of the House for the Fugitive Slave Law.  Contrast this vote with those above.  The spatial structure of the parties has begun to collapse.  The absence of a “channel” between the two parties shows a lack of party line voting.  Indeed, only 75% of the voting is accounted for by two dimensions in the 32nd.

Click image to enlarge

What finally delivered the decisive blow to the Whig Party and set the course for bloody conflict until the Civil War itself broke out in April of 1861 was the Kansas-Nebraska Act of 1854. The main dimension of conflict is now South (on the left of the first dimension) vs. North (on the right of the first dimension).

Click image to enlarge

Finally, echoing the analysis in Congress: A Political-Economic History of Roll Call Voting (chapter 5) by 1858 the Whigs were gone and the Republican Party had emerged as the unquestioned second major party to oppose the Democrats. The roll call below was on a proposal by the Democratic majority to postpone President Buchanan’s message on the admission of Kansas to the Union. The infamous Lecompton Constitution which was pro-slavery had lost in a referendum on 4 January 1858. The Kansas Constitution was accepted by the Senate but voted down in the House later in the year.

In the roll call below the Republican Party is on the anti-slavery (right side) of the first dimension and the pro-slavery forces are on the left side of the first dimension. The Whig Party was gone.

Click image to enlarge

As we argued in our last post the Republican Party in the House seems very likely to split into two factions as the result of the 2016 elections. Many Republican voters (enough to make Donald Trump the nominee) are angry at the Republican “Establishment” for not stopping President Obama on a variety of issues. The various charges that Paul Ryan is some sort of secret agent of “The Establishment” echo craziness from the days of None Dare Call it Treason (1964) and A Choice Not an Echo (1964) with their conspiracy theories about Communists and New York Bankers.

Unlike in the 1850s there is no second dimension of Congressional voting. Almost all issues — including lifestyle and affective — have been drawn into the first dimension. The split in the Republican Party will occur on this strange dimension that mixes economic and the classic “social” issues. Below is a figure we used in an earlier post showing a smoothed histogram of the 114th House:

Click image to enlarge

Suppose the split occurs somewhere to the right of Gowdy. Not everyone to the right of Gowdy listens to “talk radio from Area 51”. So some sorting out will occur between the two factions — traditional Republican Conservatives vs. “Conspiracy Republicans”. Assuming that Hillary Clinton wins the 2016 Presidential election, it is difficult to see how the Republican Party could ever again win the Presidency given the alienation of Hispanics, Blacks, and Social Liberals from the Republican Party. In addition, the traditional Internationalist Conservative Republicans will be willing to make deals with President Hillary Clinton to increase Defense Spending which will mean the end of the sequester. This will further divide the Republicans.

But what might finally trigger a realignment of the New Deal Party System are the obvious divisions in the Democratic Party that to this point have been papered over by their solid opposition to the Republicans. Income inequality has rapidly increased. The bottom 40% of the income distribution has not moved since the mid 1970s.

Click image to enlarge

Where has the money gone? To the mega-rich, especially the denizens of Wall Street who looted the economy leading up the the Great Recession. The graph below shows the spectacular run-up in wages in the Financial Sector (including insurance) relative to other sectors of the economy. No wonder all of the smart mathematics graduates from the Ivy League were lured to Wall Street!

Click image to enlarge

Finally, the runup in the share of income of the top 1% continues.

Click image to enlarge

What does this rapid rise in inequality mean for a President Hillary Clinton? Well, like Willie Sutton, she will have to go where the money is if she is going to fund all of her promises. That means she will have to steeply raise taxes on her supporters on Wall Street and the socially liberal rich. Good Luck!

The Coming Split in the House Republican Party in 2017

Although it is way to early to predict doom for the Republican Party, however, just as a snowball gets bigger when it is rolled down a hill, enough is now known that the Presidential election prospects look very bleak for the Republicans. Donald Trump is a Mountebank and will lose to Hillary Clinton with near certainty. Perhaps not as much as Barry Goldwater lost to President Johnson in 1964 or Senator McGovern lost to President Nixon in 1972, but Clinton’s victory will be at least as big as then Senator Obama’s victory over Senator McCain in 2008. If the Republican Convention in July maneuvers to give the nomination to Senator Ted Cruz (clearly the most unpopular member of Congress), Cruz will lose almost as badly as Trump and Trump’s die-hard supporters will be mad as hornets.

Assuming that the Senate flips back to the Democrats (unless there is a third Party Conservative candidate to provide cover for some of the vulnerable Republicans), how would a lopsided victory by Hillary Clinton affect the House Republicans? Suppose that Clinton subtracts 7% from every Republican’s two Party percentage from 2014 (the horizontal line in the figure below — my thanks to Gary Jacobson for suggesting this number), then the Republican Caucus would come in around 220 members. This would be enough to retain “control” but the Republican Party will be badly split by either the nomination of Trump or Cruz and it is safe to say that the far, far, right will be even less likely to be cooperative in passing necessary appropriations bills. Suppose this “suicide” caucus is to the right of 0.65 using CS DW-NOMINATE Scores and above the 57% line. This will leave 41 members to gum up the works in 2017.

Click image to enlarge

To get anything done, President Hillary Clinton will have to negotiate cross-party deals in the House. This, of course, will further infuriate the “suicide” caucus and it could lead to a permanent division within the Republican Party.

The last major Party to break up were the Whigs from 1851-1854. We may be living through an equally historic period. Time will tell.