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StatsModel Library - Tutorial

Last Updated : 25 Oct, 2025
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The StatsModels library in Python is a tool for statistical modeling, hypothesis testing and data analysis. It provides built-in functions for fitting different types of statistical models, performing hypothesis tests and exploring datasets.

  • Used in data science, economics, finance, and research fields.
  • Focuses on understanding relationships between variables.
  • Helps in performing statistical analysis easily and efficiently.
  • Provides clear, reliable, and interpretable results.
  • Useful for regression, hypothesis testing, and statistical modeling

Installing and Importing StatsModels

Installing StatsModels: To install the library, use the following command:

pip install statsmodels

Importing StatsModels: Once installed, import it using:

import statsmodels.api as sm
import statsmodels.formula.api as smf

To read more about this article refer to: Installation of Statsmodels

Commonly Used Models in StatsModels

Model TypeFunctionUse Case
Linear RegressionOLS()Predict continuous variables
Logistic RegressionLogit()Classification problems
Generalized Linear ModelsGLM()Flexible modeling with link functions
Time Series ModelsARIMA(), SARIMAX()Forecasting
ANOVAanova_lm()Comparing multiple groups
Mixed Linear ModelsMixedLM()Hierarchical or grouped data

Regression and Linear Models

Regression helps in studying how one variable affects another. Statsmodels offers several linear models to analyze and predict such relationships.

  • Linear Regression (OLS): Ordinary Least Squares (OLS) is the most basic method for linear regression in Statsmodels. It is used to model the relationship between a dependent variable and one or more independent variables.
  • For example, to predict house prices based on size price is the dependent variable and size is the independent variable.

Other commonly used regression models in Statsmodels include:

Statsmodels Tools and Tests

Once a model is built, Statsmodels provides tools to analyze data more effectively.

1. Descriptive Statistics: These help summarize data using measures like mean, median, mode, variance and standard deviation. You can also compute robust statistics such as:

2. Hypothesis Testing: Used to verify assumptions about data. It starts with a null hypothesis (no effect) and checks whether the data supports an alternative hypothesis (a difference exists). Statsmodels supports tests like:

Time Series Analysis

Time series analysis is used for data that changes over time like stock prices, sales or weather data. Statsmodels includes several models to handle such patterns.

AR/MA Models:

  • AR (AutoRegressive): Uses past values to predict current ones.
  • MA (Moving Average): Uses past errors to improve predictions.

ARIMA: Used when data shows a trend. It removes the trend (differencing) and then applies AR and MA models for better forecasting.

For advanced forecasting, check out:


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