STAT MISC - Milestone 1. Questions and Answers

STAT MISC - Milestone 1. Questions and Answers Sam counts how many people came to the local political meeting. He counts 72 people, but forgot about the 4 people sitting behind him. The percent error in his calculation is __________.  50%  -5.3%  5.6%  -2.8% RATIONALE Recall that the percent error is equivalent to the absolute difference divided by the actual value. If the actual number of people was 76, and the observed number of people was only 72, then the absolute error is: So we calculate the percentage error to be: CONCEPT Absolute Change and Relative Change 2 A sports trainer is going to do an experiment on the effect of Vitamin D supplements and his athletes. He randomly assigns all of his patients to either take Vitamin D supplements or take a placebo. What type of experimental design does this situation illustrate?  Completely Randomized  Matched-Pair  Simple Random  Randomized Block RATIONALE Since all athletes are assigned treatment or control for vitamin D randomly without considering other factors, this is called a completely randomized design. CONCEPT Completely Randomized Design 3 In a survey of small business owners, a response to which of the following questions would be qualitative?  How long have you owned a business?  How much did your business have in profits last year?  How many businesses do you own?  What type of business do you own? RATIONALE All the other options are numeric measures and can be used in arithmetic. The type of business you have is simply a descriptive measure and is therefore qualitative. CONCEPT Qualitative and Quantitative Data 4 In a bolt-manufacturing factory, it is estimated that 6% of the bolts being manufactured will be defective, with a 3% margin of error.