# Ordinary Least Squares Regression

Examples & Code

The Ordinary Least Squares Regression (OLSR) is a regression algorithm used in supervised learning. It is a type of linear least squares method utilized for estimating the unknown parameters in a linear regression model. As a regression algorithm, OLSR is used to predict continuous numerical values. It is widely used in various fields, including finance, economics, engineering, and social sciences, to analyze the relationship between variables and to make predictions based on that relationship.

{% embed url="https://youtu.be/tdtyX_5QVjg?si=caeX97nP-K6MXTVx" %}

## Ordinary Least Squares Regression: Introduction

| Domains          | Learning Methods | Type       |
| ---------------- | ---------------- | ---------- |
| Machine Learning | Supervised       | Regression |

Ordinary Least Squares Regression (OLSR) is a widely used algorithm in the field of regression. As a type of linear least squares method, it is particularly useful for estimating unknown parameters in a linear regression model. This algorithm falls under the category of supervised learning, which means that it requires labeled data to train the model.

With OLSR, the goal is to minimize the sum of squared residuals between the observed values in the dataset and the values predicted by the linear approximation. This is achieved by adjusting the coefficients of the linear equation until the optimal values are found.

OLS regression is a popular choice for simple linear regression, as it gives reliable and interpretable results. It is also widely used in multiple linear regression, where there are multiple independent variables involved.

For machine learning engineers and data scientists, OLSR is a valuable tool for predicting numerical outcomes based on other variables in the dataset. Its simplicity and accuracy make it a reliable choice for regression problems in various fields.

## Ordinary Least Squares Regression: Use Cases & Examples

Ordinary Least Squares Regression (OLSR) is a type of linear least squares method used for estimating the unknown parameters in a linear regression model. It is a popular regression algorithm used in supervised learning.

One of the main use cases of OLSR is in predicting housing prices. By using OLSR, we can estimate the relationship between various factors such as the size of the house, the number of bedrooms, and the location with the price of the house. This information can be used by real estate agents or potential buyers to make informed decisions.

Another use case for OLSR is in financial analysis, such as predicting stock prices. By using OLSR, we can estimate the relationship between various factors such as the company's financials, industry trends, and market sentiment with the stock price. This information can be used by investors to make informed decisions about buying or selling a particular stock.

OLS Regression is also used in medical research, such as predicting the risk of heart disease. By using OLSR, we can estimate the relationship between various factors such as age, blood pressure, cholesterol level, and lifestyle with the risk of heart disease. This information can be used by doctors to make informed decisions about patient care and treatment options.

Lastly, OLSR is used in marketing research, such as predicting consumer behavior. By using OLSR, we can estimate the relationship between various factors such as demographics, purchasing history, and product preferences with consumer behavior. This information can be used by businesses to make informed decisions about marketing strategies and product development.

## Getting Started

Ordinary Least Squares Regression (OLSR) is a type of linear least squares method used for estimating the unknown parameters in a linear regression model. It is a popular regression algorithm used in supervised learning.

To get started with OLSR, you will need to have a basic understanding of linear regression and the mathematical concepts involved. Once you have a grasp of these concepts, you can start implementing OLSR using Python and various machine learning libraries.

```
import numpy as np
import torch
from sklearn.linear_model import LinearRegression

# create some sample data
X = np.array([[1, 1], [1, 2], [2, 2], [2, 3]])
y = np.dot(X, np.array([1, 2])) + 3

# fit the model using numpy
beta_numpy = np.linalg.inv(X.T.dot(X)).dot(X.T).dot(y)

# fit the model using pytorch
X_torch = torch.from_numpy(X)
y_torch = torch.from_numpy(y)
beta_torch = torch.linalg.lstsq(X_torch, y_torch).solution.numpy()

# fit the model using scikit-learn
reg = LinearRegression().fit(X, y)
beta_sklearn = np.append(reg.intercept_, reg.coef_)

print("Beta using numpy: ", beta_numpy)
print("Beta using pytorch: ", beta_torch)
print("Beta using scikit-learn: ", beta_sklearn)

```

## FAQs

### What is Ordinary Least Squares Regression (OLSR)?

Ordinary Least Squares Regression (OLSR) is a type of linear least squares method used in regression analysis for estimating the unknown parameters in a linear regression model.

### What is the abbreviation of Ordinary Least Squares Regression (OLSR)?

The abbreviation of Ordinary Least Squares Regression is OLSR.

### What is the type of model used in OLSR?

OLSR is a linear regression model that assumes a linear relationship between the dependent variable and the independent variables.

### What type of learning method is used in OLSR?

OLSR is a supervised learning method, which means it requires labeled data to train the model.

### What are the advantages of using OLSR?

* OLSR is easy to implement and interpret.
* It provides accurate and unbiased estimates of the regression coefficients if the assumptions of the model are met.
* It is computationally efficient and can handle a large number of predictors.

## Ordinary Least Squares Regression: ELI5

Imagine you are a cookie factory and you need to figure out how much of each ingredient (flour, sugar, eggs, etc.) to use to make the perfect batch of cookies. You have some data on past batches and their ingredient amounts and how good they ended up being. Ordinary Least Squares Regression (OLSR) is like a recipe calculator that takes in that past data and helps you figure out the perfect balance of ingredients to use for future batches of cookies.

In technical terms, OLSR is a type of linear least squares method used in regression analysis to estimate the unknown parameters in a linear regression model. It falls under the category of Supervised Learning, meaning it learns from labeled examples that provide both the input and the desired output.

More concretely, OLSR aims to find the line that best fits a set of data points in a way that minimizes the distance between the line and the points in the vertical direction. By finding this line of best fit, OLSR can help us predict future outcomes based on past data.

For example, if we have data on the price of a house based on its square footage, we can use OLSR to find the line that best fits that data and then predict the price of a new house given its square footage.

So, OLSR is like a recipe calculator for finding the best fit line that can help us predict future outcomes based on past data.

\*\[MCTS]: Monte Carlo Tree Search [Ordinary Least Squares Regression](https://serp.ai/ordinary-least-squares-regression/)
