Question

My friend Jamie is an avid gardener. She is also a biostatistician and so she tends to notice some strange things about her garden. She has kept records of how many tomatoes her plants produce every year. She knows that, on average, her plants produce 11.5 tomatoes per day but she lost the records that would help her determine how much variability naturally exists in the number of tomatoes produced per day. Jamie suspects that hornworms (a real-life pest that devours tomato plants!) might be limiting the number of tomatoes her plants produce. This year, Jamie has determined to prevent the dreaded hornworms from getting to her crops. She and her husband take time every day to investigate for and remove the borers that they find. She hopes that this measure will yield a larger crop of tomatoes. This year her tomato plants produced a mean of 9.7 tomatoes per day (over N = 30 days) with a standard deviation of 5.3 tomatoes. Using an alpha level of .05, test whether Jamie’s efforts to prevent hornworms INCREASED her crop of tomatoes.

What is the critical statistic for this test?

Answer 1

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