Delivery service A company must decide which of two delivery services it will contract with. During a recent trial period, the company shipped numerous packages with each service and kept track of how often deliveries did not arrive on time. Here are the results: a) Compare the two services overall percentage of late deliveries. b) On the basis of the results in part a, the company has decided to hire Pack Rats. Do you agree that Pack Rats delivers on time more often? Explain. c) The results here are an instance of what phenomenon?
Important Terms Observational Study Data gathered by only witnessing individuals without guiding or stating an input on them. Designed Experiment Data gathered by an examiner on individuals then runs trials each to test one or more variables. Cofounding Variables existing variables within the student that affect the response Randomization randomly assigned themes to experiments Theoretical Method Divide the number of results in the experiment taken by total number results Empirical Method Calculating the relative frequency Relative Frequency X/n X number of successes n number of results Response and Explanatory Variables X= Response Variable = dependent Y= Explanatory Variable Independent Goal X is what causes the change in Y Probability