Final Exam Review Name

Final Exam Review Name:

On July 15, 2004, the Harris Poll released the results of a study asking whether people favored or opposed abolishing the penny. Of a national sample of 2136 adults, 59% opposed abolishing the penny.

1. Which of the following is a categorical variable in the Harris Poll?

(a) the 2004 participants

(b) whether each person favors or opposes abolishing the penny.

(d) the percent of people who oppose abolishing the penny

2. What are the observational units (individuals) in the study?

(a) the number of people who would abolish the penny in the entire population

(b) the number of people who would abolish the penny in the sample

(d) the percent of people who oppose abolishing the penny

3. Suppose that the observational units (individuals) in a study are Pennsylvania high schools. Which of the following is not a valid variable?

(a.) whether or not the school has an animal for its mascot

(b.) proportion of students scoring proficient or better on the PSSA at each school

(c.) total number of students at each school

(d.) number of high schools in Pennsylvania which have indoor pools

4. Suppose that 80% of all American students send a card to their mother on Mother's Day and that you selected a simple random sample of 400 American college students and to determine the proportion of them who send a card to their mother on Mother's Day. Suppose further that in the random sample of 400 students, 300 or 75% of them send a card to their mothers.

(a.) 80% is a parameter, 75% is a statistic.

(b.) 75% is a parameter, 80% is a statistic.

(c.) Both 75% and 80% represent statistics.

(d.) Both 75% and 80% represent parameters.

5. A sample is:

(a.) a number resulting from the manipulation of raw data according to specified rules.

(b.) a subset of a population.

(c.) a characteristic of a population which is measurable.

(d.) a complete set of individuals, objects, or measurements having some common observable characteristic.

For questions 6 and 7 use the following situation:

Suppose that 80% of all American college students send a card to their mother on Mother's Day and that you selected a simple random sample of 400 American college students and to determine the proportion of them who send a card to their mother on Mother's Day. Suppose further that in the random sample of 400 students, 300 or 75% of them send a card to their mothers.

6. Which of the following is true?

(a.) the 400 college students are the population

(b.) the sample size is 400

(c.) all college students in the world are the sample

(d.) the sample is the 300 students who send a card

7. Which of the following is the parameter of interest?

(a.) the proportion of American college students who send a card on Mother’s Day

(b.) the proportion of the 400 students in the sample who send a card

(c.) the proportion of all college students in the world who send a card

(d.) the 300 students in the sample who sent a card

Below is a list of names numbered 1 to 20. Use the random number table to randomly select 5 names from the list by starting at the beginning of the table and taking pairs of digits.

1 / Sofia / 11 / Dara
2 / Eassa / 12 / Jay
3 / Jeffrey / 13 / Nicole
4 / Shakoya / 14 / Francis
5 / John / 15 / Audrey
6 / Rebecca / 16 / Anthoula
7 / William / 17 / Hiep
8 / Johanna / 18 / Sean
9 / Allyson / 19 / Shanira
10 / Brandon / 20 / Alexis

8. What is the second name selected?

(a.) Dara

(b.) Jeffrey

(c.) Jay

(d.) Allyson

9. What is the fifth name selected?

(a.) Dara

(b.) Jeffrey

(c.) Jay

(d.) Allyson

10. Which best describes a SRS?

(a.) Gives every member of the population an equal chance of being selected.

(b.) Gives every member of the sample an equal chance of being selected.

(c.) Gives every different sample size an equal chance of being selected.

(d.) Gives every different population an equal chance of being selected.

11. You are concerned that your employees have little saved for retirement. You conduct a survey of your 100,000 employees using a simple random sample of size 47. You find that the mean of the savings of this sample of employees is $40,000 with standard deviation of $3,000.

This is an example of an…

(a) observational study since subjects are randomly assigned to groups

(b) observational study since it is based on taking a sample of a population without intervening

(d) experiment study since it is based on taking a sample of a population without intervening

12. Researchers concerned about the effects of excessive television viewing on students school performance are planning to conduct a study. Which of the following is true?

(a.) This study would be considered an observational study if they assigned one group of students to watch 4 hours of television each day and another group to not watch any television.

(b.) This study would be considered biased if they assigned one group of students to watch 4 hours of television each day and another group to not watch any TV.

(c.)This study would be considered an experiment if they assigned one group of students to watch 4 hours of television each day and another group to not watch any TV.

(d.) This study would be considered an experiment if they took a random sample of students, recorded their grades and the number of hours of television they watched.

13. A survey is to be undertaken of recent nursing graduates in order to compare the starting salaries of women and men. For each graduate, three variables are to be recorded (among others) sex, starting salary, and area of specialization.

(a) Sex and starting salary are explanatory variables; area of specialization is a response variable

(b) Sex is an explanatory variable; starting salary and area of specialization are response variables.

(c) Sex is an explanatory variable; starting salary is a response variable; area of specialization is a possible confounding variable

(d) Sex is a response variable; starting salary is an explanatory variable; area of specialization is a possible confounding variable

(e) Sex and area of specialization are response variables; starting salary is an explanatory variable.

14. A study was conducted to see if Smartfood Popcorn makes people smarter. A group of 50 participants in the study were divided into two groups. One group received Smartfood Popcorn before taking a spelling test, and the other took the test without first getting popcorn. The control group in an experiment should be designed to receive:

(a.) the opposite of the experiences afforded the experimental group.

(b.) the experiences afforded the experimental group except for the treatment under examination.

(c.) the experiences afforded the experimental group except for receiving the treatment at random.

(d.) the experiences which constitute an absence of the experiences received by the experimental group.

15. The Smartfood experiment would be said to take into account the principle of blindness if ______, and it could be said to be double-blind if ______.

(a.) the subjects are randomly assigned to either eat Smartfood or not;

those evaluating the subjects are blindfolded

(b.) the subjects are not aware of which treatment group they are in;

those evaluating the subjects are not aware of which treatment group received Smartfood

(c.) the subjects are selected at random from the population;

those evaluating the subjects are not aware of which treatment group the subjects are in

(d.) the subjects are not aware of which treatment group they are in;

the two treatment groups are never come in contact

16. An experiment is conducted to determine if the use of certain specified amounts of a drug will increase the IQ scores for students in the fifth grade.

In this experiment, IQ serves as:

(a.) a response variable

(b.) an explanatory variable

(c.) a placebo variable

(d.) a control variable

17. A new headache remedy was given to a group of 25 subjects who had headaches. Four hours after taking the new remedy, 20 of the subjects reported that their headaches had disappeared. From this information you should conclude:

(a) that the remedy is effective for the treatment of headaches.

(b) nothing, because the sample size is too small.

(d) that the new treatment is better than aspirin.

18. Which of the flowing is NOT a reason that subjects should be assigned to treatments at random?

(a) to get a random sample of the population of interest

(b) to eliminate the potential for researchers to influence the results

(d) so that the effects of variable that were not measured will likely be balanced out between the experimental groups

19. Researchers have observed that drinking red wine seems to lead to fewer men having heart attacks. More recently, others have noted that drinking red wine leads to headaches and people with headaches tend to take aspirin. Furthermore, aspirin is known to reduce the changes of having heart attacks. Given these facts, the relationship between drinking red wine and having heart attacks would be best described as being due to:

(a.) cause-and-effect.

(b.) strong correlation.

(c.) a lurking variable.

(d.) placebo effect.

20. There is a relationship between the number of drownings and ice

cream sales. This is an example of an association likely caused by:

(a) coincidence

(b) the fact that ice cream causes drownings

(d) the fact that drowning cause eating ice cream

21. An experiment was designed to investigate the effect of the amount of water and seed variety upon subsequent growth of plants. Each plant was potted in a clay plot, and a measured amount of water was given weekly. The plants that were assigned to receive more water had all been placed closer to a window that the ones that received less water. The height of the plant at the end of the experiment was measured. Which of the following is not correct?

(a) The response variable is the plant height.

(b) The explanatory variables are the amount of water and seed variety.

(c) The seeds should be randomly selected from the population of all seed varieties rather than randomly assigned to receive more or less water.

(d) The effect of the amount of water was confounded by the effect of being near the window

22. Which of the following best describes an outlier?

(a) The largest or smallest number in a distribution

(b) An observation that doesn’t fit in with the overall pattern of variability

(d) An unusually tall peak in the distribution of a variable

23. The histogram displays the percent of overweight adults in each state. Which of the following is NOT true?

(a) The distribution is symmetric

(b) In a typical state about 37% of the people are overweight

(d) 2 states have 11% overweight

The following side-by-side boxplots represent the rushing yards gained by the starting running backs in the opening game. Compare and contrast their performance.

24. Carson runs further than 5 yards about what percent of the time?

(a) 15%

(b) 25%

(d) 75%

25. _____ tends to run further. _____ is more consistent.

(a) Asika; Asika

(b) Asika; Carson

(d) Carson; Carson

26. Based on the dotplots of February temperatures for three cities, answer the following which of the following is NOT true?

(a) San Luis Obispo experienced generally higher temperatures than Sedona and Lincoln

(b) The distribution of temperatures for Sedona is skewed toward lower values

(d) The temperatures in Lincoln tend to be higher than those in Sedona

27. The measure of spread which is resistant to extreme scores on the higher or lower end of a distribution is the:

(a) median.

(b) mean.

(d) IQR

28. Making the largest number in a data set much larger will increase the ______but not change the ______.

(a) median; mean

(b) mean; standard deviation

(d) IQR; median

29. Which of the following is not a measure of center?

(a.) mean

(b.) median

(c.) mode

(d.) standard deviation

30. The dotplot to the right compares some systolic and diastolic blood pressure measurements. Which of the following is NOT true?

(a.) systolic blood pressure tends to be higher than diastolic blood pressure

(b.) systolic blood pressure reading tend to be above 100

(c.) every systolic reading is higher than every diastolic reading

(d.) diastolic blood pressure readings tend to be below 100

31. If you are told a population has a mean of 25 and a standard deviation of 0, what must you conclude?

(a.) Someone has made a mistake.

(b.) There is only one element in the population.

(c.) There are no elements in the population.

(d.) All the elements in the population are 25.