> summary(lm(attendance ~ league, data=MLBattend)) ... Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) 1716321 36259 47.33 <2e-16 *** leagueNL 127296 52093 2.44 0.015 * ...We see that the mean difference of 127,296 fans is significant with a p-value of 0.015.