  # Least-Squares Regression

Lead Author(s): University of Colorado Boulder

Source: UC Boulder PhET

Student Price: FREE

Create a scatter plot or use real-world data and try to fit a line to it! Explore how individual data points affect the correlation coefficient and best-fit line.

# Least-Squares Regression

### Topics

• Linear Regression
• Correlation
• Residuals
• Outlier
• Data

### Description

Create your own scatter plot or use real-world data and try to fit a line to it! Explore how individual data points affect the correlation coefficient and best-fit line.

### Sample Learning Goals

• Interpret r (the correlation coefficient) as data points are added, moved, or removed.
• Interpret the sum of the squared residuals while manually fitting a line.
• Interpret the sum of the squared residuals of a best-fit line as a data point is added, moved, or removed.
• Compare the sum of the squared residuals between a manually fitted line and the best-fit line.
• Determine if a linear fit is appropriate.