logarithmic scores for state-by-state predictions of U.S. presidential election 2020

score.py

from math import log2
from collections import namedtuple

StateResult = namedtuple(
    "StateResult",
    ["state", "economist", "fivethirtyeight", "predictit", "actual"],
)

state_results = [
    StateResult(
        "AK",
        economist=0.0385,
        fivethirtyeight=0.1496,
        predictit=0.11,
        actual=False,
    ),
    StateResult(
        "AL",
        economist=0,
        fivethirtyeight=0.015825,
        predictit=0.02,
        actual=False,
    ),
    StateResult(
        "AR",
        economist=0,
        fivethirtyeight=0.00965,
        predictit=0.02,
        actual=False,
    ),
    StateResult(
        "AZ",
        economist=0.7111875,
        fivethirtyeight=0.680375,
        predictit=0.52,
        actual=True,
    ),
    StateResult(
        "CA",
        economist=1,
        fivethirtyeight=0.9985,
        predictit=0.94,
        actual=True,
    ),
    StateResult(
        "CO",
        economist=0.9985625,
        fivethirtyeight=0.968775,
        predictit=0.90,
        actual=True,
    ),
    StateResult(
        "CT",
        economist=1,
        fivethirtyeight=0.999325,
        predictit=0.93,
        actual=True,
    ),
    StateResult(
        "DC",
        economist=1,
        fivethirtyeight=1,
        predictit=0.96,
        actual=True,
    ),
    StateResult(
        "DE",
        economist=1,
        fivethirtyeight=0.99995,
        predictit=0.94,
        actual=True,
    ),
    StateResult(
        "FL",
        economist=0.7855625,
        fivethirtyeight=0.684175,
        predictit=0.43,
        actual=False,
    ),
    StateResult(
        "GA",
        economist=0.569,
        fivethirtyeight=0.576525,
        predictit=0.40,
        actual=True,
    ),
    StateResult(
        "HI",
        economist=1,
        fivethirtyeight=0.993575,
        predictit=0.94,
        actual=True,
    ),
    StateResult(
        "IA",
        economist=0.3920625,
        fivethirtyeight=0.399975,
        predictit=0.26,
        actual=False,
    ),
    StateResult(
        "ID",
        economist=0,
        fivethirtyeight=0.00565,
        predictit=0.02,
        actual=False,
    ),
    StateResult(
        "IL",
        economist=1,
        fivethirtyeight=0.999275,
        predictit=0.94,
        actual=True,
    ),
    StateResult(
        "IN",
        economist=0.00025,
        fivethirtyeight=0.03475,
        predictit=0.05,
        actual=False,
    ),
    StateResult(
        "KS",
        economist=0.000875,
        fivethirtyeight=0.014875,
        predictit=0.04,
        actual=False,
    ),
    StateResult(
        "KY",
        economist=0,
        fivethirtyeight=0.01465,
        predictit=0.03,
        actual=False,
    ),
    StateResult(
        "LA",
        economist=0.00075,
        fivethirtyeight=0.02825,
        predictit=0.02,
        actual=False,
    ),
    StateResult(
        "MA",
        economist=1,
        fivethirtyeight=0.9996,
        predictit=0.95,
        actual=True,
    ),
    StateResult(
        "MD",
        economist=1,
        fivethirtyeight=0.999625,
        predictit=0.94,
        actual=True,
    ),
    StateResult(
        "ME",
        economist=0.999,
        fivethirtyeight=0.903975,
        predictit=0.87,
        actual=True,
    ),
    StateResult(
        "MI",
        economist=0.9785625,
        fivethirtyeight=0.94515,
        predictit=0.69,
        actual=True,
    ),
    StateResult(
        "MN",
        economist=0.9868125,
        fivethirtyeight=0.9577,
        predictit=0.74,
        actual=True,
    ),
    StateResult(
        "MO",
        economist=0.0143125,
        fivethirtyeight=0.063525,
        predictit=0.06,
        actual=False,
    ),
    StateResult(
        "MS",
        economist=0.0018125,
        fivethirtyeight=0.08425,
        predictit=0.06,
        actual=False,
    ),
    StateResult(
        "MT",
        economist=0.0109375,
        fivethirtyeight=0.177725,
        predictit=0.14,
        actual=False,
    ),
    StateResult(
        "NC",
        economist=0.670875,
        fivethirtyeight=0.6369,
        predictit=0.46,
        actual=False,
    ),
    StateResult(
        "ND",
        economist=0,
        fivethirtyeight=0.023825,
        predictit=0.03,
        actual=False,
    ),
    StateResult(
        "NE",
        economist=0.0000625,
        fivethirtyeight=0.005675,
        predictit=0.04,
        actual=False,
    ),
    StateResult(
        "NH",
        economist=0.982625,
        fivethirtyeight=0.891425,
        predictit=0.73,
        actual=True,
    ),
    StateResult(
        "NJ",
        economist=1,
        fivethirtyeight=0.99245,
        predictit=0.94,
        actual=True,
    ),
    StateResult(
        "NM",
        economist=0.99725,
        fivethirtyeight=0.977,
        predictit=0.88,
        actual=True,
    ),
    StateResult(
        "NV",
        economist=0.9473125,
        fivethirtyeight=0.8774,
        predictit=0.74,
        actual=True,
    ),
    StateResult(
        "NY",
        economist=1,
        fivethirtyeight=0.99995,
        predictit=0.93,
        actual=True,
    ),
    StateResult(
        "OH",
        economist=0.4134375,
        fivethirtyeight=0.4512,
        predictit=0.29,
        actual=False,
    ),
    StateResult(
        "OK",
        economist=0,
        fivethirtyeight=0.006025,
        predictit=0.03,
        actual=False,
    ),
    StateResult(
        "OR",
        economist=1,
        fivethirtyeight=0.9817,
        predictit=0.92,
        actual=True,
    ),
    StateResult(
        "PA",
        economist=0.9428125,
        fivethirtyeight=0.840575,
        predictit=0.61,
        actual=True,
    ),
    StateResult(
        "RI",
        economist=1,
        fivethirtyeight=0.9992,
        predictit=0.95,
        actual=True,
    ),
    StateResult(
        "SC",
        economist=0.01625,
        fivethirtyeight=0.09955,
        predictit=0.25,
        actual=False,
    ),
    StateResult(
        "SD",
        economist=0,
        fivethirtyeight=0.05045,
        predictit=0.05,
        actual=False,
    ),
    StateResult(
        "TN",
        economist=0,
        fivethirtyeight=0.031775,
        predictit=0.04,
        actual=False,
    ),
    StateResult(
        "TX",
        economist=0.283,
        fivethirtyeight=0.38235,
        predictit=0.30,
        actual=False,
    ),
    StateResult(
        "UT",
        economist=0.0000625,
        fivethirtyeight=0.0462,
        predictit=0.06,
        actual=False,
    ),
    StateResult(
        "VA",
        economist=0.9975,
        fivethirtyeight=0.99015,
        predictit=0.89,
        actual=True,
    ),
    StateResult(
        "VT",
        economist=1,
        fivethirtyeight=0.996075,
        predictit=0.95,
        actual=True,
    ),
    StateResult(
        "WA",
        economist=1,
        fivethirtyeight=0.99185,
        predictit=0.94,
        actual=True,
    ),
    StateResult(
        "WI",
        economist=0.97425,
        fivethirtyeight=0.942225,
        predictit=0.70,
        actual=True,
    ),
    StateResult(
        "WV",
        economist=0,
        fivethirtyeight=0.0076,
        predictit=0.03,
        actual=False,
    ),
    StateResult(
        "WY",
        economist=0,
        fivethirtyeight=0.00165,
        predictit=0.02,
        actual=False,
    ),
]


def is_swinglike(state_result):
    swing_calls = [
        0.1 < getattr(state_result, predictor) < 0.9
        for predictor in ["fivethirtyeight", "economist", "predictit"]
    ]
    return sum(swing_calls) >= 2


def score():
    scores = {"fivethirtyeight": 0, "economist": 0, "predictit": 0}
    swinglike_only_scores = {
        "fivethirtyeight": 0,
        "economist": 0,
        "predictit": 0,
    }
    losses = {}

    print(
        "{} states are swinglike".format(
            sum([is_swinglike(sr) for sr in state_results])
        )
    )

    for state_result in state_results:
        if state_result.actual is None:
            continue

        for predictor in scores.keys():

            if state_result.actual:  # Biden win
                probability = getattr(state_result, predictor)
            else:
                probability = 1 - getattr(state_result, predictor)

            subscore = log2(probability)

            scores[predictor] += subscore

            if is_swinglike(state_result):
                swinglike_only_scores[predictor] += subscore

            losses[(predictor, state_result.state)] = subscore

    return scores, swinglike_only_scores, losses


if __name__ == "__main__":
    scores, swinglike_only_scores, losses = score()
    print(sorted(scores.items(), key=lambda e: e[1]))
    print(sorted(swinglike_only_scores.items(), key=lambda e: e[1]))
    print(sorted(losses.items(), key=lambda e: e[1])[:10])