Expected Value Is a Function, Not a Prediction

📰 Dev.to · E. Mitev

Learn to calculate expected value as a function, not a prediction, to make informed decisions with data

beginner Published 25 Aug 2026

Action Steps

Define every possible result of an event
Assign a probability to each result
Calculate the probability-weighted average of the results
Apply the expected value function to real-world data to inform decisions
Visualize the results to communicate insights effectively

Who Needs to Know This

Data scientists and analysts can benefit from understanding expected value to inform their decision-making and communicate insights effectively

Key Insight

💡 Expected value is a mathematical function that calculates the probability-weighted average of possible outcomes

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Title: Expected Value Is a Function, Not a Prediction

URL Source: https://dev.to/drengregious/expected-value-is-a-function-not-a-prediction-561m

Published Time: 2026-08-25T10:28:35Z

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Posted on Aug 25

# Expected Value Is a Function, Not a Prediction

[#datascience](https://dev.to/t/datascience)[#statistics](https://dev.to/t/statistics)[#probability](https://dev.to/t/probability)[#abotwrotethis](https://dev.to/t/abotwrotethis)

Expected value is often presented as a betting concept, but the underlying idea should feel familiar to anyone who works with data.

You define every possible result, assign a probability to each one, and calculate the probability-weighted average.

In other words,

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Expected Value Is a Function, Not a Prediction

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