A polling agency conducted a survey of 100 doctors on the question "Are you willing to treat

women patients with the recently approved pill RU-486"? The conservative margin of error

associated with the 95% confidence interval for the percent who say 'yes' is

a. 50% b. 10% c. 5% d. 2%

11. Which one of these statistics is unaffected by outliers?

a. Mean

b. Interquartile range

c. Standard deviation

d. Range

12. A list of 5 pulse rates is: 70, 64, 80, 74, 92. What is the median for this list?

a. 74 b. 76 c. 77 d. 80

13. Which of the following would indicate that a dataset is not bell-shaped?

a. The range is equal to 5 standard deviations.

b. The range is larger than the interquartile range.

c. The mean is much smaller than the median.

d. There are no outliers.

14. A scatter plot of number of teachers and number of people with college degrees for cities in

California reveals a positive association. The most likely explanation for this positive

association is:

a. Teachers encourage people to get college degrees, so an increase in the number of

teachers is causing an increase in the number of people with college degrees.

b. Larger cities tend to have both more teachers and more people with college degrees, so

the association is explained by a third variable, the size of the city.

c. Teaching is a common profession for people with college degrees, so an increase in the

number of people with college degrees causes an increase in the number of teachers.

d. Cities with higher incomes tend to have more teachers and more people going to college,

so income is a confounding variable, making causation between number of teachers and

number of people with college degrees difficult to prove.

15. The value of a correlation is reported by a researcher to be r = ?0.5. Which of the following

statements is correct?

a. The x-variable explains 25% of the variability in the y-variable.

b. The x-variable explains ?25% of the variability in the y-variable.

c. The x-variable explains 50% of the variability in the y-variable.

d. The x-variable explains ?50% of the variability in the y-variable.

16. What is the effect of an outlier on the value of a correlation coefficient?

a. An outlier will always decrease a correlation coefficient.

b. An outlier will always increase a correlation coefficient.

c. An outlier might either decrease or increase a correlation coefficient, depending on

where it is in relation to the other points.

d. An outlier will have no effect on a correlation coefficient.

5. If a statistically significant difference in blood pressure change at the end of a year for the

two activities was found, then:

a. It cannot be concluded that the difference in activity caused a difference in the change in

blood pressure because in the course of a year there are lots of possible confounding

variables.

b. Whether or not the difference was caused by the difference in activity depends on what

else the participants did during the year.

c. It cannot be concluded that the difference in activity caused a difference in the change in

blood pressure because it might be the opposite, that people with high blood pressure

were more likely to read a book than to walk.

d. It can be concluded that the difference in activity caused a difference in the change in

blood pressure because of the way the study was done.

6. What is one of the distinctions between a population parameter and a sample statistic?

a. A population parameter is only based on conceptual measurements, but a sample statistic

is based on a combination of real and conceptual measurements.

b. A sample statistic changes each time you try to measure it, but a population parameter

remains fixed.

c. A population parameter changes each time you try to measure it, but a sample statistic

remains fixed across samples.

d. The true value of a sample statistic can never be known but the true value of a population

parameter can be known.

7. A magazine printed a survey in its monthly issue and asked readers to fill it out and send it

in. Over 1000 readers did so. This type of sample is called

a. a cluster sample.

b. a self-selected sample.

c. a stratified sample.

d. a simple random sample.

8. Which of the following would be most likely to produce selection bias in a survey?

a. Using questions with biased wording.

b. Only receiving responses from half of the people in the sample.

c. Conducting interviews by telephone instead of in person.

d. Using a random sample of students at a university to estimate the proportion of people

who think the legal drinking age should be lowered.

9. Which one of the following variables is not categorical?

a. Age of a person.

b. Gender of a person: male or female.

c. Choice on a test item: true or false.

d. Marital status of a person (single, married, divorced, other)

Question 3 1 pts For populations that grow exponentially ( ON = rN): which of the following populations will experience the fastest population growth rate? O A population of 1000 rabbits that has a yearly death rate of 0.01 and a yearly birth rate of 0.11 A population of 1000 wolves that has a yearly death rate of 0.01 and a yearly birth rate of 0.06 A population of 1000 elephants that has a yearly death rate of 0.01 and a yearly birth rate of 0.02 A population of 1000 blue whales that has a yearly death rate of 0.01 and a yearly birth rate of 0.01 1 ptsLab2. In a population, the birth rate and death rate are calculated as follows: " Birth Rate = Number of Births + Population ' Death Rate = Number of Deaths + Population For example, in a population of 100,000 that has 8,000 births and 6,000 deaths per year, ' Birth Rate = 8,000 + 100,000 = 0.08 - Death Rate = 6,000 + 100,000 = 0.06 Design a Population class that stores a current population, annual number of births, and annual number of deaths for some geographic area. The class should allow these three values to be set in either of two ways: by passing arguments to a three-parameter constructor when a new Population object is created or by calling the setPopulation, setBirths. and setDeaths class member functions. In either case, if a population gure less than 2 is passed to the class, use a default value of 2. If a birth or death gure less than 0 is passed in, use a default value of 0. The class should also have getEirthRate and getDeathRate functions that compute and return the birth and death rates. 1lllfrite a short program that uses the Population class and illustrates its capabilities. 1. Estimate I\" (per capita rate of increase) We know that there are 400 births in the population over the month, in our population of 3,000 individuals; we can express this as a rate by doing the following: Birth rate = 4008000 = 0.1333 birthsir (individual per month) Death rate = @6000 = 0.0500 deaths! (individual per month) I = birth rate death rate = 0.1333 0.0500 = 0.0833 2. Calculate what the population size would be in 6 months. (assume the same birth and death rates over time, i.e., the same r) using Nt=Noert 3. Calculate the population size after 6 months if you recorded 4000 births and 150 deaths for the initial population of 3000 and based r on those values. Nt = results are likely to be very accurate. 3-7 Exercises Finding Rates. In Exercises I-8, use the data given below (based on data from the U.S. Census Bureau) to find the indicated rates. Round results to one decimal place, and use a multiplying factor of k = 1000 unless indicated otherwise. Vital Statistics for the United States in One Year 00 infants Population: 285,318,000 Women aged 15-44: 61,811,000 Deaths: 2,416,000 Fetuses delivered without life after of 36.7 in Live births: 4,026,000 20 weeks of gestation: 39,900 Deaths of infants under 1 year of HIV infected persons: 900,000 age: 27.500 Deaths from HIV infections: 17,402 Deaths of infants under 28 days of ed on crude age: 18,000 Motor vehicle deaths: 43,900 Colorado, a ors (such as 1. Find the neonatal mortality rate. y rates (per 2. Find the fetal mortality rate. too surpris- r the age of 3. Find the perinatal mortality rate. for Florida 4. Find the crude birthrate. Florida has a 5. Find the general fertility rate. esidents. In- 6. Using a multiplier of & = 100,000, find the motor vehicle death incidence rate. justed rates. people aged 7. Find the HIV incidence rate. deaths due to 8. Find the HIV mortality rate for HIV-infected persons. e quite com- 9. Finding Probability An example in this section involved the crude mortality rate, such as age. which was found to be 8.5 persons per 1000 population. Find the probability of ran- ects mortality domly selecting someone and getting a person who died within the year. What advan- ment. Calcula- tage does the crude mortality rate have over the probability value? dized popula