Showing posts with label leaners. Show all posts
Showing posts with label leaners. Show all posts

Tuesday, August 19, 2008

Is Rasmussen's Inclusion of "Leaners" Affecting the Electoral College Outlook Now? An Update

It has been about three weeks since FHQ last checked in on the effect the early July decision by Rasmussen to report "leaners" in their polling releases had on our electoral college projections. At the time, only Ohio switched from favoring Obama to favoring McCain based on which version (with leaners or without) was used. In the period since though, there have been 27 new Rasmussen polls in 27 states. For 18 of those, that means the second (or third in the case of Minnesota) poll since the switch. The point of the comparison between the two types of numbers initially was to account for the discrepancy in the comparison of with leaners polls to previous without leaners polls. It just wasn't an apples to apples comparison.

With multiple "leaners" polls now out in 18 states, that really isn't the concern anymore. There are still nine states that had their first "with leaners" results reported since the beginning of August (and 13 others that have yet to have had their first with leaners poll conducted), but this is now primarily an exercise in examining how the electoral college projection would change -- and not a critique of the wholesale switch over to using the "leaners" numbers that took place in the aftermath of the change. We have the data, why not look at it? The more information we have from a "with leaners"/"without leaners" perspective, the more likely we are to begin seeing differences in the electoral college projections.

What we saw initially was that the leaners were breaking for McCain nearly across the board, but that around the time of Obama's trip abroad, that began to switch. And since that point, McCain's advantage in the "with leaners" numbers has almost been cut in half (from +1.08 to just +0.64 now). [Since the table is getting so large, I've decided to just simply append it to the end of the post instead of breaking up the text with such a mammoth figure. The new data are below the re-labelling of the columns.] Regardless, McCain continues to maintain an advantage over Obama with the leaners in these polls. And in an election that looks like it could come down to who is swinging the most independents, that's an important distinction.

But let's look at that more closely, focusing on the more recent polls (the new additions this time). Of those 27 states, eight are red states, eleven are blue states and the remaining eight are toss ups. In nine of the eleven blue states, the leaners are going for Obama (Though, it should be noted that in five of those nine, the leaners margin is exactly the same as the without leaners margin.), and in five of the red states, the leaners move in McCain's direction. So McCain in red states and Obama in blue. No real surprise there.

In the toss up states though, there are some differences. McCain holds slight advantages in 5 of those eight toss up states. The leaners broke for him in 60% of those cases (Missouri and Montana being the exceptions.). The picture for Obama was different. Of the three toss ups that favored the Illinois senator, the leaners moved toward him in one (Colorado), against him in another (Michigan) and broke even in the third (Nevada). That list of states was the very same as the one I discussed yesterday in the post about the benefits McCain could gain from tapping Mitt Romney as his running mate. Those three plus all the states in various shades of red add up to 271 electoral votes. And it is a very small consolation that Obama gains leaners in Colorado yet has the overall lead in the poll go to McCain. Nor is it beneficial to break even in Nevada when the overall poll favors McCain -- a switch from the month prior. In other words, having leaners break for him in Missouri and Montana is about all Obama can hang his hat on in this instance.

But what about the electoral college projection? Well, no matter which measure you use -- with or without leaners -- the projection (as a function of our weighted average) remains the same: 298-240 in favor of Obama. In fact, it is interesting that some of these leaner gains are cancelling each other out when subsequent polls are released. That has happened in both Minnesota and Wisconsin. Also, Nevada and Oregon have shown the same margins in both versions of the polls across two releases now.

One additional pattern that we can glean from these Rasmussen polls is the line up of states that are likely to have new polling data released in the next week. If everything holds to form, there should be new data in Arkansas, California, Florida, New Hampshire, New Mexico, Ohio and Pennsylvania in the near future. The last five of those are certainly worth keeping an eye on. All are toss ups with the exception of New Mexico. Given how other western states favoring Obama (Colorado and Nevada) have fared lately, it will be interesting to see if New Mexico follows suit.

Rasmussen Polls Since w/Leaners Distinction was Added (7/9/08)*
StateDatew/o Leaners
w/Leaners
Change
Undecideds Drop
Missouri
7/7+5
+50
-10
New Jersey
7/7+5
+3+2
-4
Illinois
7/8+13
+11+2
-6**
North Dakota
7/80
+1+1
-7**
Wisconsin
7/8+13
+10+3-6
Louisiana
7/9+20
+19+1
-2
South Dakota
7/9+4
+40
-4
Washington7/9+9
+8+1-6
Iowa
7/10+10
+100
-9
Michigan
7/10+8
+80
-5
Minnesota
7/10+18
+17+1
0
Kansas
7/14+20
+23+3
-9
North Carolina
7/15+3
+30
-5
Oregon
7/15+9
+90
-5
Nevada
7/16+2
+20
-5
Virginia
7/160
+1
+1
-6
Alaska7/17+5+5
0
-7
Arkansas7/17+10
+13+3-4
Georgia7/17+9
+11+2
+1
Maine
7/17+10
+8+2
-2
Colorado
7/21+7
+3+4-13
Ohio
7/21+6
+10+4
-7
Florida
7/22+1
+2+1-7
Minnesota
7/22+12
+13+1--***
New Hampshire
7/23+6
+4+2-5
Pennsylvania
7/23+5
+6+1-8
New Mexico
7/24+5
+6+1-6
California
7/24+12
+10+2-6
StateDatew/o Leaners
w/Leaners
Change
Undecideds Drop
Mississippi
7/28+11
+12+1-2
Nebraska
7/28+18
+19+1-3
Kentucky
7/29+10
+9+1-9
Montana
7/29+1
0+1-3
Alaska
7/30+5
+6+1--***
Arizona
7/30+16
+19+3-6
Texas
7/30+9
+8+1-7
Alabama
7/31+18
+20+2-9
Connecticut
7/31+15
+13+2-6
New Jersey
8/4+8
+10+2--***
New York
8/4+20
+19+1-2
Massachusetts
8/5+15
+16+1-6
Wisconsin
8/5+4
+7+3--***
Washington
8/6+12
+120
--***
Iowa
8/7+5
+50--***
Michigan
8/7+7
+4+3--***
Missouri
8/7+7
+6+1--***
Oregon
8/7+10
+100
--***
Kansas
8/11+15
+14+1--***
Nevada
8/11
+3
+30
--***
Illinois
8/12+15
+150
--***
Maine
8/12+13
+14+1--***
Virginia
8/12+1
+1+2--***
Colorado
8/13
+2
+1+1--***
Minnesota
8/13
+4
+40
--***
North Carolina
8/13+4
+6+2--***
Georgia
8/14+7
+9+2--***
Avg. Change+0.64-5.57
*The "with leaners" distinction was added to reports that were released beginning on 7/9/08. The date on which these polls were conducted (The ones that these releases were based on) stretches back to 7/7/08.
**Rasmussen has only conducted one poll in these states. Therefore, the difference was taken from between the with and without leaner numbers within the same poll in these cases.

***Previous poll had been taken after "with leaners" change had been made.



Recent Posts:
The New Ohio Poll and McCain's VP Choice

The Electoral College Map (8/17/08)

Which States are Underpolled in the Presidential Race?

Sunday, July 27, 2008

An Update on the Rasmussen "Leaners" and a Look at How They Affect the Electoral College

We documented earlier this week that there may be a problem with Rasmussen's decision to report two different polling results with each release and have everyone use the newer and different, "with leaners" data when reporting it secondhand or using them in an electoral college analysis. Comparing a poll from Georgia in June that had no inclusion of leaners with a poll from July that did is problematic at the very least. Below is an updated look at the polls that Rasmussen has released since the "with leaners" distinction began appearing in press releases following July 4.

Rasmussen Polls Since w/Leaners Distinction was Added (7/9/08)*
StateDatew/o Leaners
w/Leaners
Change
Undecideds Drop
Missouri
7/7+5
+50
-10
New Jersey
7/7+5
+3+2
-4
Illinois
7/8+13
+11+2
-6**
North Dakota
7/80
+1+1
-7**
Wisconsin
7/8+13
+10+3-6
Louisiana
7/9+20
+19+1
-2
South Dakota
7/9+4
+40
-4
Washington7/9+9
+8+1-6
Iowa
7/10+10
+100
-9
Michigan
7/10+8
+80
-5
Minnesota
7/10+18
+17+1
0
Kansas
7/14+20
+23+3
-9
North Carolina
7/15+3
+30
-5
Oregon
7/15+9
+90
-5
Nevada
7/16+2
+20
-5
Virginia
7/160
+1
+1
-6
Alaska7/17+5+5
0
-7
Arkansas7/17+10
+13+3-4
Georgia7/17+9
+11+2
+1
Maine
7/17+10
+8+2
-2
Colorado
7/21+7
+3+4-13
Ohio
7/21+6
+10+4
-7
Florida
7/22+1
+2+1-7
Minnesota
7/22+12
+13+1--***
New Hampshire
7/23+6
+4+2-5
Pennsylvania
7/23+5
+6+1-8
New Mexico
7/24+5
+6+1-6
California
7/24+12
+10+2-6
Avg. Change+1.00-5.7
*The "with leaners" distinction was added to reports that were released beginning on 7/9/08. The date on which these polls were conducted (The ones that these releases were based on) stretches back to 7/7/08.
**Rasmussen has only conducted one poll in these states. Therefore, the difference was taken from between the with and without leaner numbers within the same poll in these cases.

***Previous poll had been taken after "with leaners" change had been made.

Overall then, there is still a bias toward McCain in cases where "with leaners" data is replacing w the data that does not include them. As I've said, this isn't going to hae major ramifications at the outset, but over time, once a series of polls have been conducted, that collective difference could have a huge impact on what FHQ and others are doing with their electoral college analyses. In the only instance where a state has been polled by Rasmussen more than once since the switch, the results cancelled each other out. The first poll gave McCain a one point edge with leaners while the poll that followed two weeks later saw Obama with the same advantage. Such a result likely won't be the norm, however. In Ohio, for example, using one version or the other shifted the Buckeye state's 20 electoral votes from Obama to McCain and back again. And though that is the only case of a change thus far, that list is likely to grow in the future when new polling data is released.
[Click Map to Enlarge]

So looking at the map, we see that using the without leaners data -- the type that was used prior to July 9 -- shifts the map in Obama's direction with the electoral vote tally reverting to the 298-240 margin that had been in place for most of July until the new Ohio poll surfaced last week. That four point change in Ohio triggered just a 0.34 point change in our weighted average, but that is all that is necessary to move 20 vital electoral votes from one candidate's column to the other's.

It could be said that all were arguing over is whether Ohio is a toss up favoring McCain or Obama when the real point is that the Buckeye state is a toss up. Period. It doesn't really favor anyone. That's a valid point. However, there are differences in other states -- obviously -- but one poll has not been enough to affect change in those cases. Further polling, though, may bring about that change.

Note: I don't know how regularly I'm going to update these figures, but I have built them into my spreadsheet and I'm tracking the differences. When and if any changes occur -- major or minor -- I will bring them to the attention to our readers.


Recent Posts:
The Electoral College Map (7/27/08)

Guam: Oh Well, So Much for Frontloading the General Election

A Game of Vice Presidential Chicken

Wednesday, July 23, 2008

The Deal with Those Rasmussen "Leaners" [Update]

Yeah, what is the deal with that switch? On its simplest level, the chart below looks at the difference in the Rasmussen poll margins based on whether leaners were included in the data. That distinction seems to have been instituted following July 4. The polls that started coming out on July 9 began to use the language "with leaners" to describe the alternate numbers to what was in the headline. "With leaners" data gives McCain about a one point bump when we look at how the margin between McCain and Obama is affected based on whether leaners are included. It has been rare that Obama has gained once "leaners" are included with those who directly answer the candidate preference question. Interestingly, the two polls today gave the Illnois senator a boost once leaners are included.

Rasmussen Polls Since w/Leaners Distinction was Added (7/9/08)*
Statew/o Leaners
w/Leaners
Change
Undecideds Drop
Alaska+5+5
0
-7
Arkansas+10
+13+3-4
Colorado
+7
+3+4-13
Florida
+1
+2+1-7
Georgia+9
+11+2
+1
Illinois
+13
+11+2
-6**
Iowa
+10
+100
-9
Kansas
+20
+23+3
-9
Louisiana
+20
+19+1
-2
Maine
+10
+8+2
-2
Michigan
+8
+80
-5
Minnesota (7/10)
+18
+17+1
0
Minnesota (7/22)
+12
+13+10
Missouri
+5
+50
-10
Nevada
+2
+20
-5
New Jersey
+5
+3+2
-4
North Carolina
+3
+30
-5
North Dakota
0
+1+1
-7**
Ohio
+6
+10+4
-7
Oregon
+9
+90
-5
South Dakota
+4
+40
-4
Virginia
0
+1
+1
-6
Washington+9
+8+1-6
Wisconsin
+13
+10+3-6
Avg. Change+1.08-5.4
*The "with leaners" distinction was added to reports that were released beginning on 7/9/08. The date on which these polls were conducted (The ones that these releases were based on) stretches back to 7/7/08.
**Rasmussen has only conducted one poll in these states. Therefore, the difference was taken from between the with and without leaner numbers within the same poll in these cases.


The problem here is not one of the changes in the margins though. It is one of comparison. You can't directly compare the new "leaner" data to past Rasmussen polls that did not include the respondents that meet that description. Obviously if leaners are pushed in any one direction, the number of undecideds decreases. So, if we look at the data concerning undecideds plus those supporting other candidates (not McCain or Obama) in the most recent polls and in the one immediately prior to the inclusion of leaners, we get a better sense of how much the undecided total has dropped. We can look at this within each poll; looking at the with and without leaners numbers, but what we are trying to capture is the problem of comparing the new, with leaners polls with the old, without leaner polls. And what we see is that on average, the percentage of undecideds drops by more than five points per poll when leaners are included in the topline numbers. Now, we expect to see the number of undecideds drop this time of year...naturally. But we don't expect that decrease to be manufactured. And the catch is that everyone (FHQ included) has been using Rasmussen's "with leaners" numbers since the switch. The result is that comparisons and subsequent analyses--whether used for electoral college projections or not--are open to a potential bias.

In our case, here at FHQ, I took the liberty of changing data to reflect the "without leaners" view across all the Rasmussen data. I altered the margins of these 24 polls then, to pull them in line with the pre-switch polling methodology. The effect that had on our state-by-state averages was negligible. The only change was that Ohio slipped back into Obama's column (Due to the new Rasmussen poll in the Buckeye state, Ohio has moved from an Obama toss up to a McCain toss up.). Again though, that isn't the real issue. One poll among many in the average is not all that consequential. However, when we continue to compile "with leaner" polls, they collectively have the potential to skew our examination of the electoral college. And that just so happens to be contrary to what we want to accomplish with this endeavor. So let's just lop off the Rasmussen data and be done with it. Well, that deprives us of a valuable source of data. Since Rasmussen made the switch (post-July 4) there have been 43 new polls. 24 of those polls have been from Rasmussen. That's approaching 60% of the data. I don't then, want to throw Rasmussen out. What we can do is continue what we've begun here: to chart how much of a difference the "with leaners" data has on our electoral college projections. And as we do with the monthly examinations of how the averages have changed from state to state, we can observe these differences periodically as well. After a month or so, we will then be able to see if there is any significant bias attendant to including the leaner data and how large that impact is.


A belated thanks to reader, SarahLawrenceScott, for getting the ball rolling on this examination.


Recent Posts:
The Electoral College Map (7/23/08)

The Electoral College Map (7/20/08) [Update]

The Electoral College Map (7/16/08)