Test 1 Stats

21.Experimental Study

21. Determine whether an observational or experimental study is appropriate to answer the question: A general manager of a restaurant wants to identify if closing the store early on weeknights will hurt profits.

34. Weights (pounds) Frequency Relative Frequency 80-109 5 16,7% 110-139 6 20% 140-169 4 13.3% 170-199 5 16.7% 200-229 4 13.3% 230-259 4 13.3% 260-289 2 6.7%

34. Construct a grouped frequency distribution. Use 7 classes with a class width of 30 and beginning with a lower class limit of 80. Weights (pounds) Frequency Relative Frequency 80-109 110-139 140-169 170-199 200-229 230-259 260-289

39. Weight Classifications Frequency Relative Frequency Obese (over 225 lbs) 8 26.7% Overweight (166 -225 lbs) 7 23.3% Normal Weight (110 -165 lbs) 10 33.3% Underweight (under 110 lbs) 5 16.7%

39. Convert the data into the following categories (qualitative data). Weight Classifications Frequency Relative Frequency Underweight (under 110 lbs) Normal Weight (110-165 lbs) Overweight (166-225 lbs) Obese (over 225 lbs)

Population parameter

6. Determine if the numerical value describes a population parameter or a sample statistic. 75% of all freshmen at your school reside on campus.

Sample Statistics

7. Determine if the numerical value describes a parameter or a statistic. A survey of 2189 people revealed that 76% of the U.S. population eats while they drive

Descriptive Statistic

8. Determine whether the statement describes a descriptive or inferential statistic. The average number of hours students in your statistics class study per week is 5.1.

17. Quantitative 18.Discrete 19.Interval

: The IQ scores of students at the local college. 17. Classify as either qualitative or quantitative 18. Determine if the data is discrete or continuous. 19. Determine the level of measurement.

13. Qualitative 14. Ordinal

A new feature on a CD player did not work properly. The manufacturer wanted to know if this caused users any problems. The users were asked to select one of the categories given below: 1) Not a problem 2) Not very serious 3) Somewhat serious 4) Very serious 13. Classify as either qualitative or quantitative 14. Determine the level of measurement.

20.Observational Study

Determine whether an observational or experimental study is appropriate to answer the question: A deli cart entrepreneur wants to know if commuters frequent her establishment often.

Inferential Statistic

Determine whether the statement describes a descriptive or inferential statistic. A survey of 1788 people revealed that 74% have a college degree; therefore it can be assumed that 74% of the U.S. population has a college degree.

Sample

Determine whether the statement describes a population or a sample. The ages of a sample of 21 employees at a textbook company.

Population

Determine whether the statement describes a population or a sample. The price of homes of all the parents of your classmates.

Population: All students in your math class Sample: 13 out of the 23 students in your math class

Identify the population being studied and the sample chosen. The final exam scores of 13 out of the 23 students in your math class.

All tomato plants at Mr. Lonardo's greenhouse

Identify the population being studied. The heights of 10 out of the 25 tomato plants at Mr. Lonardo's greenhouse

10. Quantitative 11. Discrete 12. Ratio

The number of customers visiting a restaurant in a day. 10. Classify as either qualitative or quantitative 11. Determine if the data is discrete or continuous. 12. Determine the level of measurement .

27.Weight, in pounds 28.Quantitative 29.Continuous 30.Ratio 31.All American high school students aged 14-18 years 32.The 30 American high school students aged 14-18 years that were surveyed 33.Yes (American, high school students, aged 14-18) CHAPTER 2

What is the average weight, in pounds, of high school students aged 14-18 years? 27. What is the variable? 28. Is the variable (data) qualitative or quantitative? 29.. If quantitative, is the variable (data), discrete or continuous? 30. Is the variable (data) nominal, ordinal, interval, or ratio? 31. What is the population for the posed question above? 32. What is the sample for the posed question above? 33. Is the sample representative?

15.Qualitative 16.Nominal

When you dial another country you must first dial the country code. For example, the country code for the United States is 001 and the country code for India is 011. 15. Classify as either qualitative or quantitative 16. Determine the level of measurement .

22.Systematic 23.. Convenience 24.. Cluster 25. Stratified 26.Random

identify which type of sampling is used: random, systematic, convenience, stratified, or cluster. 22. A complete list of all Coca-Cola stockholders is compiled and every 500th name is selected. 23. At the annual Microsoft stockholders meeting, a survey is conducted of all who attend. 24. All of the Pepsi stockholder zip codes are collected and all stockholders are randomly selected from 5 different zip code. 25. A researcher divided subjects into two groups according to gender and then selected members from each group for her sample. 26. Nursing supervisors are selected using random numbers in order to determine annual salaries.