2008 Presidential Election Predictions
Intrade.com is an online options market. People can buy and sell contracts on the results of the presidential election state by state.
Projections:
| Tue Nov 4 17:20:49 PST | Democratic | Republican | field |
| Expected | 353.7 | 182.7 | 1.5 |
| Winner-Take-All | 375 | 163 | 0 |
Expected:
For each state, Intrade has a contract for Democratic, Republican, and Field (Other). For instance Ohio today has a Democratic win at 86.5%, a Republican win at 13% and Field at 0.1%. Multiply these percentages by Ohio's 20 electoral votes to get 17.3, 2.6, and 0.02 electoral votes. Similar calculations for the other states and D.C. gives the probabilistic projection of total electoral votes.
Winner-Take-All:
For each state, allocate all the electoral votes to a party with a Intrade price >50%.
Sometimes either of the calculations can give a total above or below 538 because the last trade for one party can be more recent than for the other. Also, sometimes both or neither are above 50%.
Similar websites
2008 Electoral Map Prediction
Simulating the 2008 Presidential Election
Princeton Election Consortium
electoral-vote.com
FiveThirtyEight