House 2018 Model Talk: Regression versus Simulation

"All models are wrong, but some are useful."

G. Elliott Morris

9 minute read

Up until now, my forecast of the 2018 House midterms has been pretty grim for Democrats. It has noted a 7-8 percentage point Democratic advantage in the generic ballot and calculated a 32% chance of Democrats winning control of the House majority. It has come to that conclusion via a mix of national polls, district-level predictions, and simulations designed to parameterize the error in our measurement. Today, I made an adjustment to that model, and when I ran the computer code it spit out the following:

Four Questions about Democrats Taking Back The House

The House map provides a huge upside for Democrats --- if they can get there. There are several paths to a Democratic House, and my model can help us find them.

G. Elliott Morris

24 minute read

Admittedly, my forecast for the 2018 House elections looks pretty pessimistic for the Democrats. The media has been quick to pick up on this fact, but they’re glossing over something important: Despite a grim forecast seat share, Democrats have an outside chance of winning the majority — and a landslide election. I talked through this “skew” of expectations in a twitter thread the other day: Let’s talk more about what happens if we’re wrong about the House generic ballot, according to my 2018 model.

What to Expect in the Alabama Senate GOP Primary Runoff

Roy Moore is ahead in polling of the Alabama Senate GOP primary runoff, but can we really expect this Bannon-backed ex-judge to pull off a win?

G. Elliott Morris

6 minute read

“Trump’s Big Gamble,” the New York Times headline reads, “Can He Pull Alabama Senator to Victory?” It’s certainly possible, but is it likely? According to public opinion polls, don’t count on it. Trump’s pick is trailing the opposition Roy Moore in the Alabama Senate GOP primary runoff. According to the final week of polling, incumbent appointed Senator “Big Luther” Luther Strange, is falling short of the former Alabama Supreme Court Chief Justice by nearly 10 percentage points.

G. Elliott Morris

1 minute read

From my post for The Upshot: Young Americans have been moving left and leaving the G.O.P. in recent years, but a successful Democratic coalition built on the backs of liberal youth is far from a sure thing, especially in the short term. The party’s problem is straightforward: getting them to actually go to the polls. Politicians know which part of the electorate still butters their bread — and there’s no avocado on it.

House Coverage at Decision Desk HQ

I will be writing House election coverage for the Decision Desk HQ throughout the next year, up to the 2018 midterms. I hope you'll join me!

G. Elliott Morris

1 minute read

If you follow me on Twitter, then you already know the news: I’ll be using my House election model throughout the 2018 election to cover the ebbs and flows of the 2018 midterm campaign for the Decision Desk HQ! The coverage won’t differ much from what you’ll find here on my blog, except that I’ll be publishing brief 200-300 word articles each day recapping House news from around the country. We will answer questions like “which challenger stands a chance?

G. Elliott Morris

5 minute read

Note: This article was written in conjunction with Alexander Agadjanian, a fellow political science undergraduate student at Dartmouth College. Follow him on Twitter @a_agadjanian.

Voters are often overanalyzed. They’re put into buckets based on their party or ideology. They are often assumed to have consistent policy preferences — either liberal or conservative — across various issue domains. But this is hardly the case. One of the more longstanding and well-established findings from political science research on political beliefs has been that Americans aren’t particularly ideologically coherent.

How am I Forecasting the 2018 House Midterm Election?

Combining National and Local Electoral Preferences to Forecast the 2018 US House Midterms

G. Elliott Morris

17 minute read

It has been roughly two weeks since I launched my forecasting model for the 2018 midterm elections to the House of Representatives. Current generic ballot polling gives Democrats a 7.2 percentage point edge in the national popular vote, roughly where it has been since a month after Donald Trump became president. The forecasting model estimates, contrary to what a 7.2% lead would imply, that Democrats have just a 22% chance of winning the House majority on November 6, 2018.

A Fresh Look

Some notes on web programming and a fresh new look.

G. Elliott Morris

2 minute read

To those who visit my blog frequently, the new look of this website may confuse at first. Post images are gone, colors are a little more gray, and — first and foremost — the blog looks more like a personal blog. Rest assured, you’re still at the same-old The Crosstab. Same author, same data, same outlook. But why the change? A few reasons: The old setup was getting cumbersome — creating new posts and pages required editing multiple text files each time I wanted to make something new.

Have Democrats Really Lunged Left? Maybe Not.

More Democrats identify as liberal than ever before, but key policy positions have changed little.

G. Elliott Morris

6 minute read

It is no secret that lawmakers in congress have become polarized in an asymmetric fashion, with Republican House members moving to the right far more than Democrats have moved left. However, it is entirely plausible that Democratic voters are more liberal than they used to be, even if lawmakers are not. To answer this riddle I consult the data. Is there a shift left among the party base itself, even if lawmakers have not moved?

Republican House Members Have Polarized More Than Their Democratic Counterparts

Using some cool new graphics software to look at how Congress has changed over time.

G. Elliott Morris

3 minute read

Image from: https://web.stanford.edu/~neilm/ When last we chatted, I talked of how congressional elections have shifted to reflect national politics more than local influences. Importantly, I noted that this may be less the result of ideological “polarization” — the process by which the beliefs of partisans move left/right — and more the result of partisan “sorting.” But polarization does exist, and it is real. This is especially true of elites in government: congresspeople in particular.