Question

1. Consider a study of the growth rates of teo different species of pathogenic skin bacteria. We have a growth medium and an incubator that minics the growth conditions provided by skin. We culture 15 playes of species A and 15 of species B and mearure the amount of bacteria on each plate 24 hours later. To determine whether mean grow rate differs, we did a two-group t-test to compare the means growth of these two species, with a two-sided alternative hypothesis. The 2-sided p-value for the t-ratio was 0.0047. alpha = 0.05.

a) State your conclusion in context and say why you reached that conclusion.

b) Would the confidense intervals for the difference include zero? why/why not.

Answer 1