You can use the following syntax to extract the R-squared and adjusted R-squared values from the lm() function in R:
#extract R-squared
summary(model)$adj.r.squared
#extract adjusted R-squared
summary(model)$adj.r.squared
The following example shows how to use this syntax in practice.
Example: Extract R-Squared from lm() in R
Suppose we fit the following multiple linear regression model in R:
#create data frame df frame(rating=c(67, 75, 79, 85, 90, 96, 97), points=c(8, 12, 16, 15, 22, 28, 24), assists=c(4, 6, 6, 5, 3, 8, 7), rebounds=c(1, 4, 3, 3, 2, 6, 7)) #fit multiple linear regression model model
We can use the summary() function to view the entire summary of the regression model:
#view model summary
summary(model)
Call:
lm(formula = rating ~ points + assists + rebounds, data = df)
Residuals:
1 2 3 4 5 6 7
-1.5902 -1.7181 0.2413 4.8597 -1.0201 -0.6082 -0.1644
Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) 66.4355 6.6932 9.926 0.00218 **
points 1.2152 0.2788 4.359 0.02232 *
assists -2.5968 1.6263 -1.597 0.20860
rebounds 2.8202 1.6118 1.750 0.17847
---
Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
Residual standard error: 3.193 on 3 degrees of freedom
Multiple R-squared: 0.9589, Adjusted R-squared: 0.9179
F-statistic: 23.35 on 3 and 3 DF, p-value: 0.01396
Note the values for the R-squared and adjusted R-squared of the model near the bottom of the output:
- R-squared: 0.9589
- Adjusted R-squared: 0.9179
To only extract the R-squared value for the model, we can use the following syntax:
#extract R-squared value of regression model
summary(model)$r.squared
[1] 0.9589274
And to only extract the adjusted R-squared value for the model, we can use the following syntax:
#extract adjusted R-squared value of regression model
summary(model)$adj.r.squared
[1] 0.9178548
Notice that these values for R-squared and adjusted R-squared match the values that we saw earlier in the entire regression output summary.
Additional Resources
The following tutorials explain how to perform other common tasks in R:
How to Perform Simple Linear Regression in R
How to Perform Multiple Linear Regression in R
How to Create a Residual Plot in R