400 adults are to be surveyed, what frequencies would you expect to occur for each unwanted item listed on the snapshot?
Q. 2If you want to be 80 sure you did not get your valentine something unwanted, what should you avoid buying? How does the Pareto diagram show this?
Q. 3Circle graphs (pie diagrams) show the amount of data that belong to each category as a proportional part of a circle.
Indicate whether the statement is true or false
Q. 4Circle graphs and bar graphs are graphs that are used to summarize qualitative, or attribute, or categorical data.
Indicate whether the statement is true or false
Q. 5Which of the following describes a detrended' time series?
a. It has a decreasing long-term trend in it.
b. It randomly fluctuates, sometimes with an increasing trend and sometimes with a decreasing trend.
c. It has a long-term trend that was removed in order to look for other interesting features.
d. All of the above.
Q. 6What type of statistical error is being made in the following statement? If this uphill linear trend continues, 50 years from now, one out of every three of us will be an Elvis impersonator..
a. Extrapolation
b. Exaggeration
c. Overprediction
d. Expectation
Q. 7Suppose an algebra professor found that the correlation between study time (in hours) and exam score (out of 100) is +.80, and the regression line was found to be y = 20 + 4x. He arrived at this equation through years of collecting data on his students, most of whom reported studying anywhere from 0 to 20 hours for his exams. Suppose the professor later found out that his correlation was not +.80, but rather it was +.08 . How does this change the predictions he can make about exam scores based on study time?
a. You have to take the results and divide them by 10, because .80/10 = .08.
b. It won't change the predictions because the regression line stays the same.
c. The predictions should no longer be used because they won't be very accurate.
d. Not enough information to tell.
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