Question

question determine the probability of the treatment groups mean being greater than the control groups mean by 8 points or more. then complete the statements. the significance level is set at 5%, and the probability of the result is 3.6 %, which is less than the significance level. the result is statistically significant. part b question which statement is true about the result considering a significance level of 5%? the result is statistically significant, which implies that spraying the corn plants with the new type of fertilizer does not increase the growth rate. the result is statistically significant, which implies that spraying the corn plants with the new type of fertilizer does increase the growth rate. the result is not statistically significant, which implies that spraying the corn plants with the new type of fertilizer does increase the growth rate. the result is not statistically significant, which implies that this result could be due to random chance. question 2 according to a research study, people can better manage their time when they wear watches than when they use mobile phones or other gadgets to keep track of time. to test the studys results, researchers randomized 300 college students into a treatment group and a control group. the treatment group was asked to wear a watch every day, and the control group was asked to avoid wearing a watch for 50 days. researchers noted the number of occasions when students from both groups arrived later than their scheduled time. the results of the experiment showed that the mean score of the treatment group was exactly 15 points less than the mean score of the control group. to test whether the results could be explained by random chance, the researchers created the following table, which summarizes the results of 1,000 randomizations of the data with differences of means rounded to the nearest 5 points. consider the significance level to be set at 5%, so results lower than 5% can be considered statistically significant.

Explanation:

Step1: Recall significance level concept

A result is statistically significant if the probability of the result (p - value) is less than the significance level.

Step2: Analyze given values

The significance level is 5% (0.05) and the probability of the result is 3.6% (0.036). Since 0.036 < 0.05, the result is statistically significant.

Step3: Interpret significance in context

A statistically - significant result in an experiment about a new fertilizer implies that the treatment (spraying with new fertilizer) has an effect. In this case, it implies that spraying the corn plants with the new type of fertilizer does increase the growth rate.

Answer:

The result is statistically significant, which implies that spraying the corn plants with the new type of fertilizer does increase the growth rate.