## Data collected from 538 at 11:45am on October 23, 2022

The make up of the Senate in 2022 is 50 Republicans and 50 Democrats, counting the 2 independents as Democrats. At most 11 states are in play in having probabilities that are not essentially zero or one. The 11 states ranked by the 538 probabilities for the Democratic candidate are:state
| prob
| now
| |

Colorado | 88 | D | |

New Hampshire | 81 | D | |

Arizona | 74 | D | |

Pennsylvania | 58 | R | |

Georgia | 53 | D | pivot for 50 Democratic seats |

Nevada | 46 | D | |

Ohio | 25 | R | |

Wisconsin | 24 | R | |

North Carolina | 23 | R | |

Florida | 10 | R | |

Utah | 5 | R | |

55 = 538 probability of the Democrats controlling the Senate.

If the Democrats win Georgia and all the states above it, but none of the states below it, they will have 50 seats, counting the 2 independents as Democrats. The ranking assumption thus implies that the probability of the Democrats controlling the Senate is the probability that they win Georgia, which is 53 percent. The 538 probability of the Democrats controlling the Senate is 55 percent. This probability is based on 40,000 simulations using probability distributions for each state. The computed 55 percent probability is close to the ranking assumption's probability of 53 percent, which does not require any simulations.

## Data collected from Predictit at 2:15pm on October 9, 2022

The make up of the Senate in 2022 is 50 Republicans and 50 Democrats, counting the 2 independents as Democrats. Only 11 states are in play in having market probabilities on the Predictit website less than 90 percent and greater than 10 percent. The 11 states ranked by the market probabilities from Predictit for the Democratic candidate are:state
| prob
| now
| |

Colorado | 87 | D | |

New Hampshire | 82 | D | |

Georgia | 67 | D | |

Arizona | 61 | D | |

Pennsylvania | 61 | R | pivot for 50 Democratic seats |

Nevada | 38 | D | |

Ohio | 25 | R | |

Wisconsin | 24 | R | |

North Carolina | 23 | R | |

Utah | 15 | R | |

Florida | 10 | R | |

53 = Predictit market-based probability of the Democrats controlling the Senate.

If the Democrats win Pennsylvania and all the states above it, but none of the states below it, they will have 50 seats, counting the 2 independents as Democrats. The ranking assumption thus implies that the probability of the Democrats controlling the Senate is the probability that they win Pennslyvania, which is 61 percent. The Predictit market-based probability of the Democrats controlling the Senate is 53 percent, somewhat lower that 61 percent. The market is thus not using the ranking asssumption.

## Data collected from Predictit at 3:30pm on September 25, 2022

The make up of the Senate in 2022 is 50 Republicans and 50 Democrats, counting the 2 independents as Democrats. Only 11 states are in play in having market probabilities on the Predictit website less than 90 percent and greater than 10 percent. The 11 states ranked by the market probabilities from Predictit for the Democratic candidate are:state
| prob
| now
| |

Colorado | 86 | D | |

New Hampshire | 81 | D | |

Arizona | 69 | D | |

Pennsylvania | 64 | R | |

Georgia | 51 | D | pivot for 50 Democratic seats |

Nevada | 44 | D | |

Wisconsin | 31 | R | |

North Carolina | 26 | R | |

Ohio | 23 | R | |

Florida | 13 | R | |

Utah | 13 | R | |

61 = Predictit market-based probability of the Democrats controlling the Senate.

If the Democrats win Georgia and all the states above it, but none of the states below it, they will have 50 seats, counting the 2 independents as Democrats. The ranking assumption thus implies that the probability of the Democrats controlling the Senate is the probability that they win Georgia, which is 51 percent. The Predictit market-based probability of the Democrats controlling the Senate is 61 percent, considerably higher that 51 percent. The market is thus not using the ranking asssumption.