« A Possibly Amusing Waste of Time | Main | Congresswoman Bachmann: "I was actually stunned at the arrogance." »

Nate Silver on the Senate Post 2010

While Nate Silver, the man behind the poll analysis site FiveThirtyEight, is quite liberal in his personal beliefs he manages to do a decent job not letting that bias influence his statistical approach to making sense of polls. This morning he has an interesting article where he tries to predict the makeup of the Senate after the 2010 elections.

The whole thing is worth a read. He breaks down each race state by state and considers the possible candidates (and where appropriate races where one opponent is still unknown). The part I want to quote, however, is from the beginning.

Right now, the program is showing that Democrats will retain an average of 54.7 seats in the 112th Congress. The distribution, however, is slightly asymmetrical, so the median number is 54, and the modal number is 53.

And things could, potentially, get a whole lot worse than that; the program recognizes that the outcome of the different races are correlated based on changes in the national environment. Between the surprise in Massachusetts, and races like California and Indiana which are potentially coming into play, there's about a 6-7 percent chance that Republicans could actually take control of the Senate, and another 6 percent chance or so that they could wind up with a 50-50 split. On the other hand, there's still a 7-8 percent chance that the Democrats could regain their 60th seat if the national environment shifts back in their direction.

Emphasis mine. I think that's pretty remarkable. While almost every pundit on either side of the aisle has predicted gains for the Republican party in the Senate, the idea of gaining control was typically considered a pipe dream. While a 12-13% chance is still a small chance, it is much higher than I would have assumed.

To reiterate, Silver tries to keep his politics out of his analysis. His Monte Carlo based approach proved to be accurate during the 2008 election cycle. Yes, he does always phrase things in terms of a seat going Republican as a "loss" and to a Democrat a "gain". But for our hyper-partisan readers, I'll suggest you try to get past that. His analyses are often a good read for poll junkies like myself.


TrackBack URL for this entry:

Comments (18)

"Sentate"?... (Below threshold)
Mr Spellcheck:


Nate better look at the pol... (Below threshold)

Nate better look at the poll that came out of Connecticut today. It's enough to make liberals slash their wrists. Is there a Scott Brown in Connecticut?

Thank you Mr. Spellcheck, c... (Below threshold)

Thank you Mr. Spellcheck, corrected. If only the title were actually spell-checked like the body of posts I would be saved a lot of embarrassment.

My prediction: Reps will b... (Below threshold)

My prediction: Reps will be at 53 Senate seats on Jan 1, 2011.

(Please save this comment for review on Nov 5, 2010.)

Obvious party switch: N.D.... (Below threshold)
Caesar Augustus:

Obvious party switch: N.D.

Highly vulnerable Democrat seats: NV, DE, PA, Ill, AR, CO.

Highly vulnerable GOP seats: N.H., MO.

Vulnerable Democrat seats: The Gilliland seat in N.Y. (if the GOP gets a real candidate), the open CT seat (if the GOP gets a real candidate), Boxer's seat in CA (if either Campbell or Fiorina is the candidate).

Vulnerable GOP seats: LA, N.C. Perhaps Fla. too (if Crist loses the primary, otherwise not vulnerable at all).

Interesting read but I hesi... (Below threshold)

Interesting read but I hesitate to but a good deal of stock in it. First an approach that doesn't consider all possibilities or give 100% chance when although it may be close to 100% it is definitely not, makes it an little suspicious.

Also a track record of once isn't impressive especially when it went the way he wanted it to. A bit like a Colt's fan coming up with a process that predicts the Colts going to the Super Bowl then it happens once. Chances are that his model will emphasize characteristics that the Colts are strong in while ignoring areas that he doesn't consider important;

That said, one has to start somewhere. It will be interesting how his predictions hold up. His criteria seems reasonable even if they are pretty limited.

Any model that does not acc... (Below threshold)

Any model that does not account for Scott Brown victory in MA should be thrown out.

The article represents a mo... (Below threshold)

The article represents a model that is based on what we know today in order to make early estimates of what might happen in November. A model has limitations, including available data and the assumptions that go into it.

I don't Nate would argue that any of the races are truly 100%. Schumer or Murkowski could be arrested for some heinous crime between now and election day. But barring some major change certain candidates are essentially guaranteed to win and any sensible model should predict them.

Keep in mind that it's January. Any model this far out is going to be somewhat uncertain and will need to be updated as time passes and more information becomes available.

Regarding the Scott Brown example that Z mentioned, no sensible model would have predicted more than a very small chance of a Brown win until his polls shot up late in the race. That's why some are calling it the Massachusetts Miracle. And as with any probabilistic model, getting any one race wrong wouldn't invalidate the model.

Caesar, I live in FL and th... (Below threshold)

Caesar, I live in FL and there is no chance the uber-leberal Dem Meeks beats Rubio. LA and NC are safe Rep too.

If Barry's speech today in ... (Below threshold)

If Barry's speech today in Ohio is any indication of the future, he'll have fallen apart by this November.

"Highly vulnerable Demo... (Below threshold)

"Highly vulnerable Democrat seats: NV, DE, PA, Ill, AR, CO."

As of a couple days ago CA is in play also, Boxer is 6 to 8 points behind all three Rep candidates running against her.

GrandFan "If Barry's speech today in Ohio is any indication of the future, he'll have fallen apart by this November."

Snoozer hardly covers that speech. Obama sounded like a bad city council candidate.

Did you notice he said he was in Michigan?

Last time I checked Lorain was in Ohio but maybe that changed when the 51st thru 57th states were allowed in.

Michael, I certainly hope y... (Below threshold)
Caesar Augustus:

Michael, I certainly hope you're correct.

My only concern about Rubio is the prospect of the 1994 Jeb Bush experience, where the Rats were slaughtered throughout the entire country but Jeb ran just a touch too far to the right and lost. Then again, Rubio would not be running against an incumbent, and Fla. has shifted a lot further to the red column since then. Plus I don't live there, so I'll defer.

In N.C. my concern is that Burr is a weak freshman and the Rats will wind up with a very strong candidate. Burr should win, yes, but as you know Republicans have a way of snatching defeat from the jaws of victory.

In LA my concern is ballot splitting among multiple Republicans, where Malancon gets to the runoff with around 40% of the vote. Vitter needs to win it outright in the open primary -- those Saturday runoff elections severely favor the Dems.

Obviously the Republicans are going to gain net seats, but I'm not yet convinced that it's going to be the total wipeout that many are predicting. We'll keep our fingers crossed.

Dan K.,My complime... (Below threshold)

Dan K.,

My compliments for venturing outside the RW Circle o' Pantloads.

The best informational blogs are on the left these days.

(Even the Center has been branded "left" by late Bushbots. See Larry Sabato's Crystal Ball. The only email-worthy site.411)

Barbara (call me senator) B... (Below threshold)
Zelsdorf Ragshaft III:

Barbara (call me senator) Boxer is polling at less than 50% in California. Carly Fiorina has more money than Boxer and is smarter than Boxer, who still wants to pass cap and trade. If a Republican and win in the Bay State, no Democrat is safe this election. Reid is toast.

"Carly Fiorina has more mon... (Below threshold)

"Carly Fiorina has more money than Boxer and..."-zr

Carly Fiorina is an incompetent jinx (re: HP).

Plus she has medical problems.

A definite 2 of clubs.

Put me down for a 46 D (48 ... (Below threshold)

Put me down for a 46 D (48 with the 2 weirdo's) and 52 R's.

Unfortunately there are only 19 Democrats running for re-election this cycle. Some of them that were in previously 'safe' states are finding their odds of re-election decreasing each week because of the policies they and their party support. Trying to jam a massively unpopular scheme to take over health care is going to be the stake in Dracula's heart.

Christ will probably withdraw in FL in the coming weeks as his campaign is falling apart in no small part because he's a RINO and he endorsed the Health Care bill & Obama when '0' campaigned in FL.

With the economy in shambles and unemployment hovering between an actual 17 to 20 % the party in control and proposing more spending and higher taxes is going to retain or pick up seats??? Suuuuuuuuuuuurrrrrrreeeee....

If anyone believes that they can win supporting that I have beach front property in the Arctic Circle I'd like to discuss with you.

KeithKAgreed for the... (Below threshold)

Agreed for the most part. To expand on the Brown example, yes most models would have given him at a small chance before the election and just because he won doesn't necessarily invalidate any of them that gave him a small chance. It does invalidate those, at least in part that predicted he had zero chance.

My prediction as of now for November is a net 6 to 7 Senate seat pickup for the Reps and control of the House. I know that goes against many conventional predictions but the whole House is up for reelection and I can see many supposedly safe Dem seats change hands as a result of disgust of what is going on.

Caeasar in this climate I d... (Below threshold)

Caeasar in this climate I don't think you need to be worrird. Charlie Cook recently he thought no Rep Senator's up for relection will lose in November. 2010 is toxic for the Dems. To repeat a uber lib like Meeks has no chance...none in Florida. You may be right about LA, but again this is a bad environment to have a D next to your name.






Follow Wizbang

Follow Wizbang on FacebookFollow Wizbang on TwitterSubscribe to Wizbang feedWizbang Mobile


Send e-mail tips to us:

[email protected]

Fresh Links


Section Editor: Maggie Whitton

Editors: Jay Tea, Lorie Byrd, Kim Priestap, DJ Drummond, Michael Laprarie, Baron Von Ottomatic, Shawn Mallow, Rick, Dan Karipides, Michael Avitablile, Charlie Quidnunc, Steve Schippert

Emeritus: Paul, Mary Katherine Ham, Jim Addison, Alexander K. McClure, Cassy Fiano, Bill Jempty, John Stansbury, Rob Port

In Memorium: HughS

All original content copyright © 2003-2010 by Wizbang®, LLC. All rights reserved. Wizbang® is a registered service mark.

Powered by Movable Type Pro 4.361

Hosting by ServInt

Ratings on this site are powered by the Ajax Ratings Pro plugin for Movable Type.

Search on this site is powered by the FastSearch plugin for Movable Type.

Blogrolls on this site are powered by the MT-Blogroll.

Temporary site design is based on Cutline and Cutline for MT. Graphics by Apothegm Designs.

Author Login

Terms Of Service

DCMA Compliance Notice

Privacy Policy