MATH 225N Week 8 Correlation and Causation Assignment(Q & A)

Question: True or False: The more samples taken in a scientific study, the longer the amount of time it will take to complete the research on the samples.Although there are other factors that affect study time, such as experience and equipment, increasing the number of samples will cause an increase in research time. Question: Suppose that a large controlled experiment tests whether caffeine improves reaction times. A very large number of randomly selected participants are randomly given identical-seeming pills with varying doses of caffeine (including none) and then given tests of reaction times under the same conditions. The experiment finds a strong negative correlation between caffeine dose and reaction time. (Note that lower reaction times are better.) Question: Which of the following situations could have a regression line with a negativey-intercept? Select all that apply: Question: Which of the following data sets or plots could have a regression line with a negative slope? Select all that apply. Question: Suppose that data collected from police reports of motor vehicle crashes show a moderate positive correlation between the speed of the motor vehicle at the time of the crash and the severity of injuries to the driver. Answer the following question based only on this information. Question: An experiment finds that runners with the longest legs complete a mile run in less time.Identify the relation between leg length and time of a mile run.Leg length and time of a mile run are negatively correlated…. A longer leg length is associated with a lower time of a mile run, which implies a negative relationship. There would need to be more evidence to prove causation. Question: Which of the following situations would have data sets or plots that could have a regression line with a positive slope? Select all that apply. Question: Which of the following situations could produce data sets or plots would have a regression line with a negative slope? Select all that apply.