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Who should be nominated to run in the 2012 U.S. presidential election? Long-term forecasts based on candidates’ biographies Andreas Graefe, Sky Deutschland J. Scott Armstrong, Wharton School, University of Pennsylvania This talk is an extension of : tinyurl.com/bioindex International Symposium on Forecasting Prague, June 27, 2011
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Who should be nominated to run in the 2012 U.S. presidential election?

Jan 12, 2015

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Page 1: Who should be nominated to run in the 2012 U.S. presidential election?

Who should be nominated to run in the 2012 U.S. presidential election?

Long-term forecasts based on candidates’ biographies

Andreas Graefe, Sky Deutschland

J. Scott Armstrong, Wharton School, University of Pennsylvania

This talk is an extension of : tinyurl.com/bioindex

International Symposium on ForecastingPrague, June 27, 2011

Scott Armstrong
Page 2: Who should be nominated to run in the 2012 U.S. presidential election?

Outline

1. Status-quo in election forecasting

2. Index models for forecasting elections

3. Bio-index model

4. 2012 forecasts of the bio-index model

Page 3: Who should be nominated to run in the 2012 U.S. presidential election?

U.S. Presidential Election forecasting:Evolution

1978: Economist Ray Fair publishes regression model that focuses on economic growth and inflation as predictor variables.

[Fair, 1978]

Over the next three decades, others would follow with models that use slightly different variables.

Page 4: Who should be nominated to run in the 2012 U.S. presidential election?

U.S. Presidential Election forecasting:Status quo (I)

In a brief review of 14 quantitative models by economists and political scientists

All were regression models12 used a measure of the state of the economy 7 used a measure of the incumbent’s popularity5 used both

[Jones & Cuzan, 2008]

Page 5: Who should be nominated to run in the 2012 U.S. presidential election?

Most models are economic vote models.

On average, these models perform well.

Widely-held view that a presidential election is a referendum on the incumbent president’s ability to handle the economy

Presidential campaigns, individual differences among candidates, and parties are assumed to have little impact on election outcomes.

U.S. Presidential Election forecasting:Status quo (II)

Page 6: Who should be nominated to run in the 2012 U.S. presidential election?

But what about the candidates?

Candidates play a vital role in election campaigns and are extensively discussed in the media, e.g. their

- Biography (experience)- Personality- Stands on the issues- Endorsed policies

Yet, no existing model uses such information.

Most existing models provide little help for decision-making in campaigns (e.g., Cuzan & Bundrick (1984), being an exception of fiscal policy)

Page 7: Who should be nominated to run in the 2012 U.S. presidential election?

Research with decision-making implications

Develop models that can help to advise…

A candidate’s decision on whether to run for office?

A party’s decision about who to nominate?

Decisions as to what issues a candidate should emphasize in a campaign?

Decisions as to which policies to endorse?

Page 8: Who should be nominated to run in the 2012 U.S. presidential election?

Improving the PollyVote forecast

Combining forecasts is most beneficial if one uses forecasts from different methods that use different information.

[Armstrong, 2001]

Index model forecasts should contribute to the accuracy of the combined forecast.

Page 9: Who should be nominated to run in the 2012 U.S. presidential election?

Outline

1. Status-quo in election forecasting

2. Index models for forecasting elections

3. Bio-index model

4. 2012 forecasts of the bio-index model

Page 10: Who should be nominated to run in the 2012 U.S. presidential election?

The first index model for forecasting electionsLichtman’s 13 Keys to the White House, has been published for

years. He made forecasts of the past 38 presidential elections (7 prospectively).

[Lichtman, 2008]

In all cases, the model’s predictions of the popular vote winner have been correct. No other approach has come close to this record.

From 1984 to 2004, Lichtman’s “Keys” yielded forecast errors of the popular vote shares almost as low as three established econometric models.

[Armstrong & Cuzán, 2006]

Current forecast for 2012: Obama 55.0%.

Page 11: Who should be nominated to run in the 2012 U.S. presidential election?

The issue-index model(tinyurl.com/issueindexmodel)

Predicts U.S. presidential election winners based on how voters expect the candidates to handle the issues

Examples: economy, budget deficit, Afghanistan, health care

Correctly predicted the winner in 9 of the 10 elections from 1972 to 2008 and thereby outperformed polls, prediction markets, and many econometric models.

[Armstrong & Graefe, 2011]

Current forecast for 2012: Obama 54.1%(check out pollyvote.com for continuous coverage)

Page 12: Who should be nominated to run in the 2012 U.S. presidential election?

Outline

1. Status-quo in election forecasting

2. Index models for forecasting elections

3. Bio-index model

4. 2012 forecasts of the bio-index model

Page 13: Who should be nominated to run in the 2012 U.S. presidential election?

Prediction problem

Forecast U.S. presidential election outcome from information about candidates’ biographies

Page 14: Who should be nominated to run in the 2012 U.S. presidential election?

Condition 1: Few observations

Biographical data were collected for the candidates of the two major parties for the 29 U.S. Presidential Elections from 1896 to 2008.

Page 15: Who should be nominated to run in the 2012 U.S. presidential election?

Condition 2: Large number of variables

The bio-index uses 59 variables.

Examples: - Single child - Prestigious college- Intelligence - Political positions held- Weight - Military experience- Age - Race- Education - Gender

Page 16: Who should be nominated to run in the 2012 U.S. presidential election?

Condition 3: Much domain knowledge

Large body of literature in psychology on the effect of biographical traits on leadership

[Antonakis, 2011: Predictors of leadership]

- Traits that objectively matter (e.g., intelligence, height)- Traits that seemingly matter (e.g., facial competence,

physical attractiveness)

We expected that voters are influenced by both types of traits when making their voting decisions.

Page 17: Who should be nominated to run in the 2012 U.S. presidential election?

Example of a biographical factor: Facial competence

Prior research found that facial competence led to

- 68% correct predictions in U.S. Congressional elections

[Todorov et al., 2005]

- 72% correct predictions in French parliamentary elections, even by children

[Antonakis & Dalgas, 2009]

- May and August 2007: Most competent looking candidates were Clinton & Obama for the 11 Democrats, and McCain, for the 13 Republicans

[Armstrong et al., 2011]

Page 18: Who should be nominated to run in the 2012 U.S. presidential election?

Bio-index

For each variables, the directional impact on election outcome was determined based on

- prior research (e.g. intelligence, height, beauty, facial competence)

- common sense (e.g. married, not divorced, has children)

Page 19: Who should be nominated to run in the 2012 U.S. presidential election?

CodingFour coders searched candidate’s biographies, fact books,

encyclopaedias and used data from prior studies or polls.

Yes / no variablesEach candidate was assigned a score of 1 if he possessed a

certain trait (at the time of the election campaign) and 0 otherwise

Examples: Orphan, Single child, Not divorced, Governor,…

Comparative variablesEach candidate was assigned a score of 1 if he scored higher

than his opponent on a particular cue and 0 otherwiseExamples: Height, IQ, beauty

Page 20: Who should be nominated to run in the 2012 U.S. presidential election?

Procedure for predicting the winner

Calculate the overall index score for each candidate.

Decision rule (Bio-index heuristic)

Predict the candidate with the higher index score to win the popular two-party vote.

Page 21: Who should be nominated to run in the 2012 U.S. presidential election?

Performance of the Bio-index heuristic

- Correctly predicted 27 out of 29 elections winners; - Hit rate: 93% correct predictions- Missed Carter in 1976 and Clinton in 1992

- Higher hit rate than - Election Eve Gallup polls (15 of 19), - Election Eve prediction market forecasts (22 of 26), and the - average of three established regression models (12.5 of 15.5)

- Relying only on information from the respective election year- Providing long-term forecasts

Page 22: Who should be nominated to run in the 2012 U.S. presidential election?

Bio-index model for predicting vote-shares

The simple heuristic performs well in predicting the winner.

But it does not allow for predicting the popular vote share.

Bio-index modelSimple linear regression to relate the relative index score (I) of

the incumbent to the popular vote (V)

Vote equation: V = 18.0 + 0.65 * I

Page 23: Who should be nominated to run in the 2012 U.S. presidential election?

Bio-index vs. 7 regression models (1996-2008)

Model Date of forecast 1996 2000 2004 2008 MAE

Bio-index January 4.4 2.3 0.4 0.2 1.8

Norpoth January 2.4 4.7 3.5 3.6 3.5

Abramowitz Late July 2.1 2.9 2.5 0.6 2.0

Fair Late July 3.5 0.5 6.3 2.2 3.1

Wlezien and Erikson Late August 0.2 4.9 0.5 1.5 1.8

Lewis-Beck and Tien Late August 0.1 5.1 1.3* 3.6 2.5

Holbrook Late August 2.5 10.0 3.3 2.0 4.4

Campbell Early September 3.4 2.5 2.6 6.4* 3.7

* Predicted wrong election winner

Absolute error of out-of-sample forecasts for the past four elections Bio-index MAE as low as MAE of most accurate modelBio-index forecast calculated long before the forecast of most other model

Page 24: Who should be nominated to run in the 2012 U.S. presidential election?

Limitations of the bio-index

CostsMust summarize prior knowledge about the field.Must have various coders

Acceptability Easy to understand and thus easy to criticize.

People wrongly believe that complex methods are necessary to solve complex problems. They exhibit a general resistance to simple solutions.

[Hogarth, in press]

Page 25: Who should be nominated to run in the 2012 U.S. presidential election?

Benefits of bio-indexSimple to use and easy to understand.

Contributes to accuracy of the PollyVote by using a different method and drawing upon different information

Can aid political decision-making

1. Can help political parties in nominating candidates for office.

2. Can help political candidates to decide whether to run for office.

Page 26: Who should be nominated to run in the 2012 U.S. presidential election?

Outline

1. Status-quo in election forecasting

2. Index models for forecasting elections

3. Bio-index model

4. 2012 forecasts of the bio-index model

Page 27: Who should be nominated to run in the 2012 U.S. presidential election?

Candidate

Chance to win GOP nomination Chance to win

election (Intrade**)

Index score difference

Index model forecast

RCP polls**Intrade**

5.3 17.1 6.6 +1 50.3

David Petraeus 0 0.1 0 0 49.5

Newt Gingrich* 7.1 1.3 1.0 -2 47.9

Donald Trump 0 0.2 0.6 -2 47.9

Michele Bachmann* 6.3 9 2.8 -2 47.7

Rudy Giuliani 11.0 1.8 0 -3 47.0

Mitt Romney* 24.4 35.6 16.5 -4 46.3

Tim Pawlenty* 4.9 9.8 4.0 -4 46.1

Rick Santorum* 3.7 0.6 0.2 -4 46.1

Jon Huntsman* 1.3 9.6 5.4 -5 45.3

Sarah Palin 16.0 5.1 3.2 -5 44.6

Ron Paul* 6.9 2.4 1.7 -6 44.4

Mike Huckabee 0 0.2 0.2 -6 43.8 Herman Cain* 9.3 2.0 1.3 -7 43.0

* Announced to run; **RCP and Intrade forecasts as of June 25, 2011

Page 28: Who should be nominated to run in the 2012 U.S. presidential election?

Candidate

Chance to win GOP nomination Chance to win

election (Intrade**)

Index score difference

Index model forecast

RCP polls**Intrade**

Rick Perry 5.3 17.1 6.6 +1 50.3

David Petraeus 0 0.1 0 0 49.5

Newt Gingrich* 7.1 1.3 1.0 -2 47.9

Donald Trump 0 0.2 0.6 -2 47.9

Michele Bachmann* 6.3 9 2.8 -2 47.7

Rudy Giuliani 11.0 1.8 0 -3 47.0

Mitt Romney* 24.4 35.6 16.5 -4 46.3

Tim Pawlenty* 4.9 9.8 4.0 -4 46.1

Rick Santorum* 3.7 0.6 0.2 -4 46.1

Jon Huntsman* 1.3 9.6 5.4 -5 45.3

Sarah Palin 16.0 5.1 3.2 -5 44.6

Ron Paul* 6.9 2.4 1.7 -6 44.4

Mike Huckabee 0 0.2 0.2 -6 43.8 Herman Cain* 9.3 2.0 1.3 -7 43.0

* Announced to run; **RCP and Intrade forecasts as of June 25, 2011

Page 29: Who should be nominated to run in the 2012 U.S. presidential election?

Summary

The bio-index predicts a tough time for Republicans to gain back the White House.

Of 14 potential nominees, currently only Texas Governor Rick Perry achieves an index score higher than Obama.

Limitations:- - Some variables have not yet been estimated

(e.g., facial competence, intelligence, weight).

- The bio-index model ignores much information such as performance and ability to handle issues.

The primary concern is with finding candidates that are within the index score range of Obama.

Page 30: Who should be nominated to run in the 2012 U.S. presidential election?

Are you fit to be president?

You think you know a candidate who could win against Obama in 2012?

Or, you want to test your own chances to win?

Check out the Are you fit to be president? test at

www.pollyvote.com

Page 31: Who should be nominated to run in the 2012 U.S. presidential election?

Conclusions

We used the index method to develop the bio-index, which is based on 59 cues about candidates’ biographies.

The bio-index correctly predicted the winner in 27 of the last 29 U.S. Presidential Elections.

Out of 14 potential Republican nominees, only Rick Perry is predicted to defeat Obama in a potential 2012 showdown

PollyBio contributes to the accuracy of long-term election forecasting and can help parties to select candidates running for office

Further improvements in accuracy are expected based on the index method – which itself can be used in many other applications.

Page 32: Who should be nominated to run in the 2012 U.S. presidential election?

Conditions for forecasting U.S. Presidential Elections

Conditions for forecasting U.S. Presidential Elections

Condition favoring

Multiple regression Index method

Few observations

(data on about 25 elections)

Many variables

Much domain knowledge

(e.g., expertise, prior studies, polls)

Conditions favoring the index method. In particular, if one wants to incorporate individual differences between candidates.

Page 33: Who should be nominated to run in the 2012 U.S. presidential election?

Outline

1. Status-quo in election forecasting

2. Index models for forecasting elections

3. Bio-index model

4. 2012 forecasts of the bio-index model

5. Future applications of the index method

6. Conclusions

Page 34: Who should be nominated to run in the 2012 U.S. presidential election?

Future work on index models (1)

Predict the election outcome based on how voters perceive the candidates’ personalities.

E.g., which of the candidates is more likable, honest, etc.

Implications for decision-making:- Helps candidates to decide whether to run- Helps parties to decide who to nominate

Page 35: Who should be nominated to run in the 2012 U.S. presidential election?

Future work on index models (2)

Predict the election outcome based on how voters agree with candidates’ positions on policies.

Implications for decision-making:- Helps candidates to decide which policies to pursue.

Examine policies related to issues such as gun control, income taxes, free trade, abortion, government spending to see which candidate is closest to the opinions of the voters on more policies.

Page 36: Who should be nominated to run in the 2012 U.S. presidential election?

The Index Model Challenge

Index method will be more accurate than econometric models in situations with

- many variables- much prior knowledge (especially experiments)

and- lack of data, measurement errors, and

collinearity.

Examples: Selecting CEOs, drafting athletes, marriages, economic growth rates of nations, value of real estate, medical treatments, effectiveness of ads.

Page 37: Who should be nominated to run in the 2012 U.S. presidential election?

Background: PollyVote.com project

The PollyVote project was begun in 2003 to demonstrate the value of forecasting principles by applying them to election forecasting.

The initial focus was on combining forecasts.