\begin{Schunk}
\begin{Sinput}
 reg.mod.3 <- lm(posAffect ~ ethnicity, data = dat)
 summary(reg.mod.3)
\end{Sinput}
\begin{Soutput}
Call:
lm(formula = posAffect ~ ethnicity, data = dat)

Residuals:
     Min       1Q   Median       3Q      Max 
-2.00610 -0.40094 -0.01907  0.49390  1.06360 

Coefficients:
                  Estimate Std. Error t value Pr(>|t|)    
(Intercept)         2.9364     0.1026  28.628   <2e-16 ***
ethnicityBlack      0.0697     0.1777   0.392    0.695    
ethnicityHispanic   0.1237     0.1284   0.964    0.336    
ethnicityWhite      0.1536     0.1099   1.398    0.163    
---
Signif. codes:  
0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Residual standard error: 0.6323 on 376 degrees of freedom
Multiple R-squared:  0.005664,	Adjusted R-squared:  -0.00227 
F-statistic: 0.7139 on 3 and 376 DF,  p-value: 0.5442
\end{Soutput}
\end{Schunk}
