
 Term          Contrast Estimate Std. Error     z Pr(>|z|)    2.5 %   97.5 %
   hp       mean(dY/dX)   -0.024     0.0154 -1.56 0.118721  -0.0542  0.00616
  cyl mean(6) - mean(4)   -5.968     1.6393 -3.64 0.000272  -9.1806 -2.75473
  cyl mean(8) - mean(4)   -8.521     2.3261 -3.66 0.000249 -13.0799 -3.96183

Prediction type:  response 
Columns: type, term, contrast, estimate, std.error, statistic, p.value, conf.low, conf.high 

