Editing R (programming language) (section)

=== Modeling and plotting ===
[[File:Plots from lm example.svg|right|thumb|200px|Diagnostic plots from plotting "model" (q.v. "plot.lm()" function). Notice the mathematical notation allowed in labels (lower left plot).]]
The R language has built-in support for [[data modeling]] and graphics. The following example shows how R can generate and plot a [[linear model]] with residuals.
<syntaxhighlight lang="r">
# Create x and y values
x <- 1:6
y <- x^2

# Linear regression model y = A + B * x
model <- lm(y ~ x)

# Display an in-depth summary of the model
summary(model)

# Create a 2 by 2 layout for figures
par(mfrow = c(2, 2))

# Output diagnostic plots of the model
plot(model)
</syntaxhighlight>

Output:
<syntaxhighlight lang="rout">
Residuals:
      1       2       3       4       5       6       7       8      9      10
 3.3333 -0.6667 -2.6667 -2.6667 -0.6667  3.3333

Coefficients:
            Estimate Std. Error t value Pr(>|t|)   
(Intercept)  -9.3333     2.8441  -3.282 0.030453 * 
x             7.0000     0.7303   9.585 0.000662 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

Residual standard error: 3.055 on 4 degrees of freedom
Multiple R-squared:  0.9583, Adjusted R-squared:  0.9478
F-statistic: 91.88 on 1 and 4 DF,  p-value: 0.000662
</syntaxhighlight>