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2008 ELECTION MODELA Monte Carlo Electoral Vote SimulationUpdated: September 22
Press REFRESH after linking to a graph to view the latest update
Chart State Poll Aggregate + Projection Trend Chart National 5-Poll Moving Average Projection Chart State vs. National: Vote Share Projection Trends Chart Battleground-State Polls Chart Battleground-State Win Probability Chart Obama Electoral Vote Simulation Frequency Chart Electoral Vote + Win Probability Trend Chart Electoral Vote + Projected Vote Share Trend Chart Undecided Voter Allocation + Win Probability Chart Monte Carlo Electoral Vote Simulation Trials 2008 Election Model Fraud Analyzer Uncounted & Switched Votes Chart Effect on Obama Projected Vote Share Chart Effect on Obama Projected Electoral Vote This State National State National Monte Carlo Simulation Update Poll 5-Poll 2-party 2-party Expected 9/22/2008 Aggregate Average Projection Projection Electoral Vote Obama McCain 47.01 (50.77) 45.58 (49.23) 48.67 (52.05) 44.83 (47.95) 51.46 48.54 52.57 47.43 330 208
15-Poll
End
Sample
Poll
NATIONAL MODEL Pre Undecided Voter Allocation 5-Poll Mov Avg 2-Party Projection (60% UVA) 5-Poll Mov Avg Trend Gallup Rasmussen Hotline/FD CNN Quinnipiac
CBS/NYT Zogby Ipsos Pew Resrch Newsweek
AP/gFk FOX News NBC/WSJ CBS/NYT CNN
Registered V vs Likely V Poll Averages
Date 9/21 9/21 9/21 9/21 9/16
9/16 9/15 9/15 9/14 9/11
9/10 9/09 9/08 9/07 9/07
Size 2796 RV 3000 LV 915 RV 697 LV 987 LV
800 LV 1008 LV 1046 RV 2307 LV 1038 RV
812 RV 900 RV 1000 RV 655 RV 942 RV RV avg LV avg Total
MoE 1.85% 1.79% 3.24% 3.71% 3.12%
3.46% 3.09% 3.03% 2.04% 3.04%
3.44% 3.27% 3.10% 3.83% 3.19%
Obama 48 48 47 51 49
49 47 45 46 46
44 42 46 44 48
45.6 48.3 46.7
McCain 44 47 42 47 45
44 45 45 46 46
48 45 45 46 48
45.4 45.7 45.5
Other 8 5 11 2 6
7 8 10 8 8
8 13 9 10 4
9.0 6.0 7.8
Spread 4 1 5 4 4
5 2 0 0 0
(4) (3) 1 (2) 0
0.1 2.7 1.1
Obama 48.7 48.5 48.0 48.2 47.2
46.6 45.6 44.6 44.8 44.4
44.8 45.4 45.0 44.6 45.0
McCain 44.8 45.0 44.7 45.2 45.0
45.2 46.0 46.0 46.0 46.0
46.4 46.6 46.6 48.4 47.2
Spread 3.8 3.5 3.3 3.0 2.2
1.4 (0.4) (1.4) (1.2) (1.6)
(1.6) (1.2) (1.6) (3.8) (2.2) Win Prob 98.5 98.0 86.2 80.2 77.3
66.7 44.5 30.9 26.3 28.4
30.9 34.8 29.0 14.8 23.2
Obama 52.57 52.4 52.4 52.2 51.9
51.5 50.6 50.2 50.3 50.2
50.1 50.2 50.0 48.8 49.7
McCain 47.43 47.6 47.6 47.8 48.1
48.5 49.4 49.8 49.7 49.8
49.9 49.8 50.0 51.2 50.3
Spread 5.1 4.8 4.8 4.3 3.8
3.0 1.3 0.5 0.6 0.3
0.2 0.4 0.1 (2.4) (0.6)
Win Prob 99.7 99.6 92.7 87.3 88.1
80.5 65.8 56.2 62.1 54.1
51.8 54.8 51.0 27.0 42.2
Obama’s EV and Popular Vote Win Probability is on the RiseAssuming that the election is held today (and is fraud-free), the Election Model projects that there is a better than 99% probability that Obama would win the election. His expected electoral vote margin is 330– 208 with a 51.46% two-party vote share. He also leads the National model (based on the latest 5 national polls) with 52.57% of the vote — giving him a 99.7% popular vote win probability. The EV win probability is a simple calculation: Obama won 4926 of 5000 simulated election trials. His win probability is therefore 98.5% (4926/5000). View the Election Model Electoral Vote Simulation Frequency chart. The model is a snapshot in time. Ideally, the weighted average vote shares would be identical in both the national and state models. But if they are, it’s just a coincidence; state polls lag the national polls. View the State vs. National Vote Share Projection Trend. The base case scenario assumes that Obama will win 60% of the undecided vote. And this is conservative; he is presumed to be the challenger, since McSame is running for the third Bush term). Note that the national polls lead the state polls, so that we can expect a rise in Obama’s expected EV and win probability. The national model also assumes that he will win 60% of the undecided vote. The probability that he will win the popular vote is over 99% — again assuming zero fraud, fairly accurate polls with the election held today. If Obama captures just 50% of the undecided vote, he is expected to win by 311–227 EV with a 50.6% vote share and a 96% win probability. The probability of winning the electoral vote is very close to the probability of winning the popular vote. In other words, if the projected vote share is nearly tied, the probability of winning the electoral vote will also be close to 50%. Democrats are strongest in high EV urban states, and Republicans are strong in low EV rural states. That’s why Obama can win the Electoral vote with slightly less than 50% of the total popular vote. The sensitivity analysis (see below) shows that if Obama wins 40% of the undecided vote, he will have 50.0% of the 2-party vote, 290 electoral votes and an 80% win probability. The fivethirtyeight.com site projects Obama with a 311.5–226.5 EV lead and a 74.4% win probability. Obama would surely win more than 74% of the trials in a Monte Carlo simulation with that expected EV split, unless they are factoring in a fraud component without saying so. As of Sept. 22, electoral-vote.com has Obama leading by 273– 265; realclearpolitics has Obama by 219– 189 (130 tossup). But the 2008 Election Model ( EM) has Obama leading by 330– 208. Why the difference? THE 2008 ELECTION MODEL
Last Aggregate 5-poll 2-party 2-party Monte Carlo Simulation Update State National State National Expected 9/22/2008 Average Average Projection Projection Electoral Vote 60% UVA Obama McCain 47.01 45.58 48.67 44.83 51.46 48.54 52.57 47.43 330 208 Nov 1, 2004 Final Election Model 75% UVA Kerry Bush 47.88 46.89 47.80 46.60 51.80 48.20 51.77 48.23 337 201 Sensitivity Analysis — Impact of Uncounted and Switched Votes on Obama Uncounted 1% 2% 3% Switched 2% 4% 6% Vote% 50.4 49.4 48.4 EV 303 272 240 Vote% 50.2 49.2 48.1 EV 289 257 227 Vote% 49.9 48.9 47.9 EV 274 244 213 Sensitivity Analysis — Impact of Aggregate State Projected Vote Share Undecided Voter Allocation Scenario Base Case Obama 40% 50% 60% 75% 80% Projected 2-Party Vote Share Obama McCain 50.0 50.0 50.7 49.3 51.46 48.54 52.6 47.4 52.9 47.1 MoE Obama Popular Vote Win Probability (Normdist) 1.0 % 2.0 % 3.0 % 47.9 49.0 49.3 91.9 75.8 68.0 99.78 92.3 82.9 100.0 99.4 95.3 100.0 99.8 97.3 Obama Electoral Vote (Monte Carlo - 5000 election trials) Mean Median 289.9 289.0 311.2 311.0 330.4 332.0 355.2 358.0 362.2 364.0 Maximum Minimum 385 210 382 224 400 244 417 268 420 283 Obama Electoral Vote Win Probability (Monte Carlo) Trial Wins Probability 4009 80.2 4808 96.2 4978 99.56 4999 99.98 5000 100.0 95% EV Confidence Interval Upper Lower 337 243 358 265 375 286 392 319 396 329 States Won Obama 25 25 29 29 29
2008 POLLING ANALYSIS AND PROJECTIONS National Model — see atopState Model(2-party vote shares) L A T E S T S T A T E P O L L OBAMA vs KERRY MONTE CARLO EV SIMULATION Pre-Undecided Voter Allocation 60% UVA Projection 75% UVA Projection WPE (IM) Exit Poll Actual Recorded Obama
Obama
Sprd*wt
Battlegrnd
EVote
State
AL AK AZ AR CA
CO CT DC DE FL
GA HI ID IL IN
IA KS KY LA ME
MD MA MI MN MS
MO MT NE NV NH
NJ NM NY NC ND
OH OK OR PA RI
SC SD TN TX UT
VT VA WA WV WI WY Poll Date 9/17 9/17 9/14 7/14 9/14
9/17 9/16 9/13 9/15 9/17
9/17 9/12 9/9 9/17 9/17
9/18 9/10 9/12 9/12 9/10
9/5 8/5 9/17 9/18 9/16
9/15 9/8 9/17 9/21 9/15
9/16 9/16 9/15 9/18 9/8
9/17 9/11 9/15 9/18 9/13
9/17 9/9 8/20 9/16 9/13
9/13 9/21 9/10 9/16 9/17 9/10 EV 538 9 3 10 6 55 9 7 3 3 27 15 4 4 21 11 7 6 8 9 4 10 12 17 10 6 11 3 5 5 4 15 5 31 15 3 20 7 7 21 4 8 3 11 34 5 3 13 11 5 10 3 Obama 47.0 % 306 34 38 39 37 52
48 55 90 53 45
42 63 27 56 46
54 31 37 38 50
52 49 53 52 37
45 42 34 45 51
51 50 52 46 41
47 32 48 47 59
45 37 32 44 28
58 49 48 45 50 34 McCain 45.6 % 232 60 55 56 47 36
42 37 9 42 46
54 32 68 38 47
41 63 55 54 40
38 37 42 44 55
49 53 60 46 45
42 43 40 47 55
45 64 43 45 36
51 54 56 54 64
36 46 43 49 47 62 Diff 1.43 74 (26) (17) (17) (10) 16
6 18 81 11 (1)
(12) 31 (41) 18 (1)
13 (32) (18) (16) 10
14 12 11 8 (18)
(4) (11) (26) (1) 6
9 7 12 (1) (14)
2 (32) 5 2 23
(6) (17) (24) (10) (36)
22 3 5 (4) 3 (28) Obama 51.46 364 37.6 42.2 42.0 46.6 59.2
54.0 59.8 90.6 56.0 50.4
44.4 66.0 30.0 59.6 50.2
57.0 34.6 41.8 42.8 56.0
58.0 57.4 56.0 54.4 41.8
48.6 45.0 37.6 50.4 53.4
55.2 54.2 56.8 50.2 43.4
51.8 34.4 53.4 51.8 62.0
47.4 42.4 39.2 45.2 32.8
61.6 52.0 53.4 48.6 51.8 36.4 Final Kerry 51.80 337 42.0 39.8 48.8 50.5 55.8
50.8 56.5 86.3 57.8 52.3
46.5 52.5 38.3 57.0 41.3
54.5 39.3 42.8 49.0 58.3
56.3 70.8 54.3 55.0 47.3
49.3 41.3 37.3 50.5 51.5
56.0 50.5 60.0 49.3 42.5
52.3 36.3 54.5 53.8 62.0
44.3 46.5 49.3 40.0 29.3
58.3 48.5 55.0 49.5 54.8 33.5 JK Unadj 52.49 353
42.3 40.6 45.0 45.7 60.7
50.6 62.9 91.5 61.9 51.5
42.4 58.7 32.6 57.1 40.8
51.2 37.5 40.3 44.0 56.1
60.2 66.4 55.0 56.3 49.5
49.5 37.6 37.4 53.4 57.8
58.1 53.6 65.1 50.0 35.0
54.6 34.2 51.9 55.7 62.7
46.2 36.3 43.6 42.4 28.4
67.2 50.3 57.4 40.7 52.6 32.9 JK Vote 48.76 252
37.2 35.9 44.8 45.0 54.9
47.5 54.9 90.1 53.9 47.6
41.8 54.6 30.6 55.4 39.7
49.7 37.0 40.1 42.6 54.1
56.5 62.6 51.7 51.6 40.2
46.6 39.0 33.0 48.4 50.7
53.5 49.5 59.0 44.0 35.9
49.2 34.8 51.9 51.4 60.0
41.3 38.8 43.0 38.6 26.3
59.5 45.9 53.4 43.6 50.2 29.4 Final Proj (0.34) 27
(4.4) 2.5 (6.8) (3.9) 3.5
3.3 3.3 4.3 (1.7) (1.9)
(2.1) 13.5 (8.3) 2.6 9.0
2.5 (4.7) (1.0) (6.2) (2.2)
1.7 (13.4) 1.8 (0.6) (5.5)
(0.6) 3.8 0.4 (0.1) 1.9
(0.8) 3.7 (3.2) 1.0 0.9
(0.4) (1.9) (1.1) (2.0) 0.0
3.2 (4.1) (10.1) 5.2 3.6
3.4 3.5 (1.6) (0.9) (3.0) 2.9 Unadj EP (1.03) 11 (4.7) 1.6 (3.0) 0.9 (1.5)
3.4 (3.1) (0.9) (5.9) (1.1)
2.0 7.3 (2.6) 2.5 9.4
5.8 (2.9) 1.5 (1.2) (0.1)
(2.2) (9.0) 1.0 (1.9) (7.7)
(0.9) 7.4 0.2 (3.0) (4.4)
(2.9) 0.6 (8.3) 0.2 8.4
(2.8) 0.2 0.6 (3.9) (0.7)
1.2 6.1 (4.4) 2.8 4.4
(5.6) 1.7 (4.0) 7.9 (0.8) 3.5 Exp EV 330.5 33.5
0.0 0.0 0.0 0.3 55.0
8.8 7.0 3.0 3.0 15.6
0.0 4.0 0.0 21.0 5.9
7.0 0.0 0.0 0.0 4.0
10.0 12.0 17.0 9.8 0.0
2.7 0.0 0.0 2.9 3.8
14.9 4.9 31.0 8.1 0.0
16.2 0.0 6.7 17.0 4.0
0.8 0.0 0.0 0.3 0.0
3.0 10.9 10.5 1.2 8.1 0.0 Win Prob 99.8 99.6
0.0 0.0 0.0 4.8 100.0
97.5 100.0 100.0 99.8 57.8
0.3 100.0 0.0 100.0 53.9
100.0 0.0 0.0 0.0 99.8
100.0 100.0 99.8 98.4 0.0
24.6 0.7 0.0 57.8 95.2
99.5 98.0 100.0 53.9 0.1
81.1 0.0 95.2 81.1 100.0
10.1 0.0 0.0 0.9 0.0
100.0 83.6 95.2 24.6 81.1 0.0 Rank 100%
2.4
19.2
7.8
0.9
4.9
3.6 1.1
0.9
10.7
12.5
2.5 13.1
2.1
6.9 3.9 2.2 5.3
Evote 17 192
9
27
11
10
11
5 4
5
15
20
7 21
8
13 11 5 10
Flip (*) 9 112
AL AK AZ AR CA
CO* CT DC DE FL*
GA HI ID IL IN*
IA* KS KY LA ME
MD MA MI MN MS
MO MT NE NV* NH
NJ NM* NY NC* ND
OH* OK OR PA RI
SC SD TN TX UT
VT VA* WA WV WI WY
Why Election Model projections differ from the Media, Academia and the BloggersThere are a variety of election forecasting models used in academia, the media and internet election sites. The corporate MSM (CNN, MSNBC, FOX, CBS, etc.) sponsors national polls to track the “horserace” and state polls to calculate the electoral vote. If just 2% of votes cast are uncounted (2.74% were in 2004) and 4% of Obama’s votes are switched electronically to McCain, McCain will win by 293–245 EV with 51.2% of the two-party vote.• The EM uses Monte Carlo (MC) simulation method to calculate the probability of winning the electoral vote. Monte Carlo is widely used to analyze diverse risk-based models when an analytical solution is impractical or impossible. The EM is updated weekly based on the latest state and national polls. The model projects the popular and electoral vote, assuming both clean and fraudulent election scenarios. The EM allocates the electoral vote based on the state win probability in calculating a more realistic total Expected EV. • Corporate MSM pollsters and media pundits use state and national polling data. Electoral vote projections are misleading, since they are calculated based on the latest state polls regardless of the spread; the state poll leader gets all of its electoral votes. This is statistically incorrect; they do not consider state win probabilities. And there is no adjustment for the allocation of undecided voters. For example, assume that McCain leads by 51–49% in each of five states with a total of 100 electoral votes. Most models would simply assign the 100 EV to McCain. But that is an oversimplification: Obama could easily win one or more of the states, since his win probability is 31% :
- The state projected vote share V(i) is the state poll share PS(i) plus the undecided voter allocation UVA(i):
V(i) = PS(i)+UVA(i), for i=1,51 states
For this example, a final Obama projected vote share V(i) = .49 for all states is assumed (with distinct state poll shares PS(i) and respective undecided voter allocations UVA(i) implied). Five states total 100 EV.
- The probability P(i) of winning each state assuming a 4% polling MoE (95% confidence):
P(i) = NORMDIST ( V(i), 0.5, .04/1.96, true )
.31 = NORMDIST( .49, 0.5, .04/1.96, true) for each of the 5 states (the NORMDIST function is available in Excel) The 2008 Election Model would allocate 31% of 100 EV to Obama and 69% of 100 EV to McCain. • Bloggers also track state and national polls and do not adjust for undecided voters. A few use Monte Carlo simulation, but the EV win probabilities and frequency distributions are NOT consistent with the polling data. Either the state win probabilities and/or the simulation algorithm is incorrect. • Academic regression models predict the popular vote but are run months prior to the election. They are typically based on economic and political factors rather than state or national polling data. They do not project the electoral vote. In 2004, virtually all of them forecast Bush to win by 5-10%. But since the election was stolen, the models had to be wrong — they didn’t factor election fraud as an independent variable in the regression. In fact, they never even mentioned the F-word in describing their methodologies. Fixing the polls: Party ID, Voted in 2000, RV vs. LVThere has been much discussion regarding the recent McCain “surge” in the national polls. Most national and state polls are sponsored by the corporate MSM. Gallup, Rasmussen and other national polls recently increased the Republican Party ID percentage weighting. This had the immediate effect of boosting McCain’s poll numbers. But there are 11 million more registered Democrats than registered Republicans. USA Today/Gallup changed the poll method from RV to LV right after the Republican convention. Party-ID weights were manipulated to favor McCain as well. There is a consistent discrepancy between Registered Voter (RV) and Likely Voter (LV) Polls. The Democrats always do better in RV polls. No wonder: Since 1988, Democratic presidential candidates have won new voters by an average 14% margin. The manipulation of polling weights is nothing new. Recall that the 2004 and 2006 Final National Exit Polls weightings were adjusted to match the recorded vote miscount. But all category cross-tabs had to be changed, not just Party ID. Of course, the Final Exit Poll (state and national) is always matched to the Recorded vote, even though it may be fraudulent — as it was in 2000, 2002, 2004 and 2006. This cannot be emphasized enough. Say it loud, again and again. In 2004, the 12:22am National Exit Poll (NEP) had a 38– 35 Democrat/Republican 'Party ID' mix. Kerry won the 12:22am Preliminary NEP by 51– 48%. ( 13,047 random sample, 1% MoE ) The mix was changed to 37– 37 in the Final NEP to 'force' a match to the Recorded vote;Bush won the 1:25pm 'forced' Final NEP by 51–48%. Likewise, the Gore/Bush 'Voted 2000' weights were changed from 39– 41 to 37– 43 in the Final ('13047' & '13660' here). Bush was the official winner by 50.7–48.3% with 286 EV. The final 2004 Election Model projection indicated that Kerry would win 337–201 EV with 51.8% of the 2-party vote. In their Jan. 2005 report, exit pollsters Edison-Mitofsky provided the average exit poll discrepancy for each state based on 1250 total precincts. Kerry won the unadjusted aggregate state exit poll vote share by 52.0–47.0% (2-party 52.5%) with 337 electoral votes — exactly matching the Election Model!
In the 2006 midterms, the 7pm Preliminary NEP had a 39–35 Democratic/Republican weighting mix. The Democrats won that NEP by 55–43%. But the weights were changed to 38–36 in the Final NEP in order to match the 52–46% recorded vote; the Dem 12% margin was cut in half. Once again, the 'Voted 2004' weights were transformed: from Bush/Kerry 47–45 at 7pm to 49–43 in the Final. The landslide was denied; 10-20 Dem seats were stolen.
The “dead heat” claimed by pollsters, bloggers and the media is a canard — unless they are factoring fraud into their models and not telling us. The media desperately wants a horserace, and so they fail to adjust the polls for undecided and newly registered voters. They avoid McCain’s gaffes, flip-flops and plagiarisms, while he supports the most unpopular president in history.
Polling data source: Electoral-vote.com RealClearPolitics.com
The Election Calculator Model The 2004 Election Calculator was developed as a response to the Final 2004 National Exit Poll. The Final was forced to match the recorded vote using impossible weightings. Read more about the 1988-2004 Election Calculator here.
The 2008 Election Calculator projects Obama will win the True Vote by 71 – 59m. Read more about the 2008 Election Calculator here.
The Great Election Fraud Lockdown: Uncounted, Stuffed and Switched Votes
Professional statistical organizations, media pundits and election forecasters who projected a Bush victory never discuss Election Fraud. On the contrary, a complicit media has been in a permanent election fraud lockdown, as it relentlessly promotes the fictional propaganda that Bush won BOTH elections. They want you to believe that Democrats always do better in the exit polls, because Republican voters are reluctant responders. But they never consider other, more plausible explanations — such as uncounted votes and stuffed ballots. Read more here.
Apparently, the MSM and election fraud naysayers are unaware that millions of ballots are either uncounted or stuffed. And that these anomalies have always favored a Bush: in 1988, 1992, 2000 and 2004. That is one reason why the Democratic True vote (and exit poll share) is always greater than the Recorded vote.
The MSM does not want you to know the facts and assumes that you won’t analyze pre-election and post-election exit poll anomalies or review the discrepancies between the census and recorded vote totals. And if you do, expect to be labeled as a spreadsheet wielding conspiracy freak.
These are the facts:
a) In most states, total votes cast exceeded votes recorded (uncounted ballots exceeded stuffed). In Florida, Ohio and about 10 other states, total votes recorded exceeded votes cast (ballot stuffing exceeded uncounted ballots).
b) The majority (70-80%) of uncounted ballots are in Democratic minority precincts. In 2000, according to the 2004 Census, a net 5.4 million of 110.8m total votes cast (4.9%) were uncounted, of which approximately 4.0m were Gore votes.
c) In 2004, Bush won the recorded vote by 62–59m with 286 EV. But 3.4m of 125.7 million total votes cast were uncounted (2.7%) and 2.5m were for Kerry. Adding back the uncounted votes, the recorded Bush 3.0m margin is cut in half, 62.9 - 61.5m.
Repeat a lie often enough, and it becomes conventional wisdom. Although the media commissioned exit polls which indicated that Kerry won by 5%, they never explained why mathematically impossible weights were used in the Final Exit Poll to 'force' a match to the recorded vote count.
In the Three-Card Monte con, the mark is tricked into betting that he can find the money card among three face-down cards. A rigged election is the Vote Scam equivalent of the Three-card Monte. What you see in the exit polls is not what you get in the recorded count; the recorded vote is never equal to the True vote. In this con game, the voter is the mark. Any model which correctly calculates the True vote is doomed to fail in a rigged election.
Allocating Undecided Voters: Sensitivity Analysis
In the 2008 Election Model, Obama is considered to be the challenger, since McCain is running for Bush’s third term. Typically, challengers win 60–90% of the undecided vote (UVA), if the incumbent is unpopular.
The State Model includes a sensitivity (risk) analysis of five Obama undecided voter (UVA) scenario assumptions ranging from 40–80%, with 60% as the base case. This enables one to view the effects of various projection assumptions on the expected electoral vote and win probability. Electoral vote forecasting models which do not provide a risk factor sensitivity analysis are incomplete.
The National Model calculates a 5-poll moving average projection assuming the 60% UVA scenario.
In 2004, final state and national Pre-Election Polls had the race nearly tied at 47%. Bush had a 48% approval rating. That’s one reason why the Gallup poll projected that Kerry would win 88% of the late undecided vote.
The 2004 Election Model allocated 75% of the undecided vote to Kerry as the base case of a five UVA sensitivity analysis. It projected that Kerry would have an expected 337 electoral votes with 51.8% of the two-party vote and a 99% electoral vote win probability.
Calculating the Expected Electoral Vote: A Simple Summation
It’s hard to understand why election forecasting blogs and academics and the media, who employ the latest state polls as input to their models, don’t use basic probability, statistics and simulation concepts in forecasting the electoral vote and corresponding win probability.
A meta-analysis or simulation is not required to calculate the expected electoral vote. Of course, the individual state vote projections depend on the particular forecasting method used.
This is the procedure in the 2008 Election Model for calculating the expected electoral vote:
- The state projected vote share V(i) is the state poll PS(i) plus the undecided voter allocation UVA(i):
V(i) = PS(i)+UVA(i), for i=1,51 states
- The probability P(i) of winning each state assuming a 4% polling MoE (95% confidence):
P(i) = NORMDIST ( V(i), 0.5, .04/1.96, true )
- The expected electoral vote EVS(i) for each state (win probability times electoral vote):
EVS(i) = P(i)* EV(i)
- The total expected electoral vote EV as the sum of the state electoral votes:
EV = Σ EVS(i), for i = 1,51 states
Calculating the Probability of Winning the Electoral Vote: Monte Carlo Simulation
The Excel-based Election Model is very straightforward as shown above. After updating the database for the latest state polling data, the vote shares are projected. The normal distribution function calculates the corresponding state win probability. The expected state EV is the product of the win probability and electoral vote. The sum of the 51 state expected EVs is the total expected EV.
The final step is to calculate the EV Win Probability. The Election Model uses a Monte Carlo (MC) simulation. MC is widely used for analyzing complex systems, when an analytical solution is prohibitive due to the virtually infinite number of possible combinations of risk-based variables (i.e. state win probabilities). A random number generator (RND) is used in the simulated election trials. The EV win probability is just a simple division: the number of winning election trials divided by 5000 (total trials).
The Monte Carlo mean and median EV of the election trials match are always within one of the EV summation formula. This proves that 5000 election trials are sufficient to derive a theoretically accurate win probability. The simulation illustrates the Law of Large Numbers (LLN).
With all due respect to Professor Sam Wang, his Meta-Analysis program is an unnecessarily complex combinatorial algorithm when compared to Excel and Monte Carlo simulation for calculating the expected Electoral Vote and Win Probability.
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