Equation 1 · Part 3 · Futures Methods and Technological Scenarios in Practice: An Advanced Technical Guide

Symbol i

B = \frac{1}{N}\sum_{i=1}^{N} (p_i - o_i)^2

i

What this part means

i appears in the bound of this sum. The bound states where the repeated operation starts, ends, or which values it includes.

Its job in the formula

i appears in the bound of this sum. The bound states where the repeated operation starts, ends, or which values it includes.

Full expressionSymbol iArticle meaning

The passage around this formula

The Brier score is the mean squared error between a stated probability and the binary outcome (1 if it happened, 0 if it did not): $B = \frac{1}{N}\sum_{i=1}^{N} (p_i - o_i)^2$ . where $p_i$ is the forecaster’s stated probability on question i and $o_i$ $\in$ \{0,1\} is the realized outcome. Lower is better; a perfectly calibrated coin-flip forecaster scores 0.25 on a 50/50 question, and a forecaster who says 100 percent and is wrong scores the maximum possible 1.0.

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Learn the underlying idea

A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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Sources cited in the article section

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