Abstract

http://ssrn.com/abstract=1902850
 
 

Citations (6)



 


 



Combining Forecasts: An Application to Elections


Andreas Graefe


Ludwig Maximilians University of Munich - Department of Communication Science and Media Research

J. Scott Armstrong


University of Pennsylvania - Marketing Department

Randall J. Jones


University of Central Oklahoma

Alfred G. Cuzan


University of West Florida

January 28, 2013

International Journal of Forecasting, 30(1), 43-54
Revised and extended version of a paper presented at the American Political Science Association (APSA) 2011 Annual Meeting

Abstract:     
We summarize the literature on the effectiveness of combining forecasts by assessing the conditions under which combining is most valuable. Using data on the six U.S. Presidential elections from 1992 through 2012, we then report the reduction in error obtained by averaging forecasts within and across four election forecasting methods: poll projections, expert judgment, quantitative models, and the Iowa Electronic Markets. Across the six elections, the resulting combined forecasts were on average more accurate than each of the component methods. The gains in accuracy from combining increased with the number of forecasts used, especially when these forecasts were based on different methods and different data, and in situations involving high uncertainty. Combining yielded error reductions ranging from 16% to 59%, compared to the average errors of the individual forecasts. This improvement is substantially greater than the 12% reduction in error that had been previously reported for combining forecasts.

Number of Pages in PDF File: 27

Keywords: election forecasting, combining, prediction markets, polls, econometric models, expert judgment

JEL Classification: C53, E17, C40

Accepted Paper Series





Download This Paper

Date posted: August 1, 2011 ; Last revised: August 30, 2014

Suggested Citation

Graefe, Andreas and Armstrong, J. Scott and Jones, Randall J. and Cuzan, Alfred G., Combining Forecasts: An Application to Elections (January 28, 2013). International Journal of Forecasting, 30(1), 43-54; Revised and extended version of a paper presented at the American Political Science Association (APSA) 2011 Annual Meeting. Available at SSRN: http://ssrn.com/abstract=1902850

Contact Information

Andreas Graefe (Contact Author)
Ludwig Maximilians University of Munich - Department of Communication Science and Media Research ( email )
Geschwister-Scholl-Platz 1
Munich, 80539
Germany
HOME PAGE: http://www.andreas-graefe.org
J. Scott Armstrong
University of Pennsylvania - Marketing Department ( email )
700 Jon M. Huntsman Hall
3730 Walnut Street
Philadelphia, PA 19104-6340
United States
215-898-5087 (Phone)
215-898-2534 (Fax)
HOME PAGE: http://marketing.wharton.upenn.edu/people/faculty/armstrong.cfm

Randall J. Jones
University of Central Oklahoma ( email )
100 North University Drive
Edmond, OK 73034
United States
Alfred G. Cuzan
University of West Florida ( email )
11000 University Parkway
Pensacola, FL 32514-5750
United States
Feedback to SSRN


Paper statistics
Abstract Views: 2,150
Downloads: 426
Download Rank: 38,834
Citations:  6

© 2014 Social Science Electronic Publishing, Inc. All Rights Reserved.  FAQ   Terms of Use   Privacy Policy   Copyright   Contact Us
This page was processed by apollo2 in 0.406 seconds