Refer to the fungus growth data of Exercise 12.2.7. For these data. SS(resid) = 16.7812.
(a) Calculate the standard error of the slope, SEbl.
(b) Consider the null hypothesis that laetisaric acid has no effect on growth of the fungus. Assuming that the linear model is applicable, state in symbols the null hypothesis about the true regression line and an alternative hypothesis that laetisaric acid inhibits growth of the fungus.
(c) How many degrees of freedom are there for the test in part (b)?
(d) The sample slope, b1, is -0.7120. Compute the value of the test statistic.
(e) The P-value for the test is 1.16 × 10-9. If a = 0.05, state your conclusion regarding the null hypothesis in the context of this setting.