An investigation was carried out to compare cycling behaviour in…
Question Answered step-by-step An investigation was carried out to compare cycling behaviour in… An investigation was carried out to compare cycling behaviour in secondary students traversing an obstacle course on their bicycle with and without a schoolbag. Ten children from a single year 9 class volunteered to participate. Each child cycled as fast as they could around a 148m long obstacle course. Each child negotiated the course one at a time in turn. An hour later, they repeated the trial this time carrying a 6kg backpack. The same backpack was used by all participants.Times (in seconds) to complete the course are shown in the table below.Image transcription textSubject Time without Time withDifference backpack backpack 1 53 68-15 2 47 73 -26 33 74 -41 … Show more… Show moreQuestion 1.1 A hypothesis test was carried out to see if there is statistically significant evidence of a difference in time to complete the course with and without the backpack.Why is a t-test of differences the appropriate test for this situation?Select the best reason. A. There are two groups.B. We have paired data.C. There are two independent groups.D. We are interested in the relationship between wearing a backpack and time to complete the course. Question 1.2 Select the correct alternative hypothesis for this test. A. There is a difference in the mean time to complete the course between having a backpack and not.B. Wearing a backpack is associated with slower cycling.C. There is no relationship between time to complete the course and wearing of a backpack.D. The true mean time to complete the course is the same with and without a backpack. Question 1.3 The formula for the t-test statistic is (mean difference – hypothesised value) ÷ standard error.What is the value of the standard error to 3dp? Answer Question 1.4 Below is output from RStudioImage transcription text> t. test (cycle_times$Difference,mu=0) One Sample t-test data:cycle_times$Difference t … Show more… Show moreUse the drop-down boxes to correctly state the decision for this test with reason. As the p-value is Answersmallerlarger than 0.05, we find in favour of the Answernullalternative. Question 1.5 What is the correct conclusion for this hypothesis test? A. The true mean time to complete the course is the same with and without a backpack.B. There is evidence of difference in the mean time to complete the course between having a backpack and not.C. Wearing a backpack is associated with slower cycling.D. Wearing a backpack is associated with faster cycling. Question 1.6 What information does the confidence interval add to the conclusion?Select the best answer. A. On average, the cycling time is quicker with a backpack than without.B. The confidence interval reinforces the conclusion but adds no further information.C. On average, the cycling time is slower with a backpack than without.D. The time to complete the course is faster when students do it a second time. Question 1.7 A statistician raised a number of concerns about the design of this experiment. Which of the following is not a problem? A. Only year 9 students were included.B. The students were volunteers.C. The students might have gotten faster because they had already done the course.D. They used the same backpack. Question 1.8 Another researcher says a better experimental design is to randomise the order in which students completed the course with some students doing it with the backpack before they do it without.a) Which hypothesis test would be appropriate for this situation? A. t-test of differences.B. two-sample t-test.C. Chi-squared testD. We need the data before we can decide on the test. b) This is a better experimental design than the first study because A. it is an experiment not an observational study.B. the students are randomly selected.C. it addresses lurking variables by pairing students.D. it addresses the lurking variable of experience. Math Statistics and Probability STATS 161111 Share QuestionEmailCopy link Comments (0)
