Adjusted R^2 = 1 - ((1 - R^2) * (n - 1) / (n - k - 1))
Where:
- `R^2` is the regular R-squared.
- `n` is the total number of observations (data points).
- `k` is the number of predictors (independent variables) in the model.
### Explanation:
- **R-squared (`R^2`)** measures how much of the variation in the dependent variable is explained by the independent variables in the model. However, it can increase simply by adding more variables, even if they do not improve the model's accuracy.
- **Adjusted R-squared** corrects this by considering the number of predictors. It adjusts the R-squared value downwards when unnecessary variables are added to the model.
### In Simple Terms:
- **When more variables are added to the model**, adjusted R-squared shows whether those variables actually contribute to a better fit or just add unnecessary complexity.
- **If adjusted R-squared is significantly lower than R-squared**, it indicates that the additional variables are not improving the model.
Thus, adjusted R-squared gives a more reliable measure of how well the model explains the data, especially when dealing with multiple predictors.
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