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Logit

As explained in Statistics Every Programmer Needs

Log odds are the natural logarithm of the odds of an event, calculated as the logarithm of its probability divided by the complement probability.

A logit is the natural logarithm of an event’s odds: log(p/(1 − p)), where p is the event probability and 1 − p is its complement. Logistic regression models the log odds of a binary outcome rather than modeling the outcome directly. section 5.0 section 5.1

In logistic regression, each coefficient estimates the change in log odds associated with a one-unit increase in its predictor. The model then passes the resulting linear combination through the sigmoid function to obtain a probability between 0 and 1 for an outcome coded 0 or 1. section 5.1

Interpreting a logistic-regression coefficient

For a predictor X with coefficient β, increasing X by one unit changes the modeled log odds by β. The sigmoid transformation converts the model’s resulting value into the predicted probability of the binary outcome. section 5.1

How Statistics Every Programmer Needs covers it

How deep it goes
Defines the log-odds scale and coefficient interpretation, then connects it to sigmoid-based probability prediction without deriving estimation.
Examples
Uses predictor coefficients to explain one-unit changes in log odds and sigmoid transformations to produce binary-outcome probabilities.
What it assumes
Assumes probability, complements, predictors, coefficients, and binary outcomes coded as 0 and 1.
What you can do after
Evaluate/understand logistic-regression coefficients as changes in binary-outcome log odds before probability conversion.
How it connects
Connects logistic regression, binary outcomes, coefficients, probability, odds, and the sigmoid function.

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This explainer was generated by Manning's knowledge graph from the text of Statistics Every Programmer Needs. The section links point to the parts of the book it draws on.