Minitab work - Assignment Example

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In an experiment to investigate the effect of fertiliser on mean yield of an arable crop, 20 different plots were used. Fertiliser A was applied to 10 randomly plot and B was applied to the remaining plots .After a specified time, the yield (in coded units) for each plot was measured giving the following data
i)Perform an F test to see whether assumption of equal variances in the two fertiliser yield group is reasonable .To three decimal places, what is the p value from this F test? is it reasonable to assume that the two fertiliser yields have equal variance
ii)Assuming that the F test suggest that we can pool the variances ,perform a hypothesis test to test whether there is significant difference in fertiliser mean yields (using a two sample t test with pooled variance). What is the value of the t-statistic? What is the value of the pooled variance used in this test ?To three decimal places, what is the p value from the test? Is there evidence to reject the null hypothesis of no difference in means at 5% significance level?
iii)Suppose that instead of the data arising from 20 different plots, there were in fact only 10 plots ,each of which was divided into 2 subplots. For each plot, Fertliser A was applied to randomly selected subplot and fertiliser B was applied to other subplot.
Perform an appropriate hypothesis test to see whether there is evidence that the average difference between the yield from Fertiliser A and B is not zero .To three decimal places, what is the p value from the test? Is there evidence to reject the null hypothesis that the average of the differences is zero, t the 5%signifcance level?
Condition ‘x’ is a medical condition from which 70% of people recover within 7 days if left untreated. The health service would like to increase this proportion by treating sufferers .An experiment was, therefore, conducted to test a new drug ...Download file to see next pagesRead More