Student: _____________________
Date: _____________________
1.
Instructor: Doug Ensley
Course: MAT117 01 Applied Statistics Assignment: Online 01 ­ Chapter 1
­ Ensley
Frequency Distribution
heaven
1: yes, definitely
Do you 2: yes, probably
believe in 3: no, probably not
heaven?
4: no, definitely not
hell
1: yes, definitely
Do you 2: yes, probably
believe in 3: no, probably not
hell?
4: no, definitely not
#
718
640
267
165
%
40.1
35.8
14.9
9.2
1,033
618
221
152
51.0
30.5
10.9
7.5
a. What are the percentages for the four possible outcomes in heaven?
What percentage of people said "yes, definitely?"
%
What percentage of people said "yes, probably?"
%
What percentage of people said "no, probably not?"
%
What percentage of people said "no, definitely not?"
%
b. Which percentage of "yes, definitely" responses was a. What are the percentages for the four possible higher?
outcomes in heaven? b. Is the percentage of "yes, definitely" responses higher for belief in heaven or hell?
A. Heaven
B. Both were the same
C. Hell
2. One year a survey asked a group of people from a certain country the following question, "How many good friends do you have ?" Of the 841 people who responded, 2 % reported having only 1 good friend. Identify (a) the sample, (b) the population, and (c) the statistic reported.
(a) What is the sample for this survey?
A. The sample is the 2 % who reported having only one good friend.
B. The sample is the public in the particular country.
C. The sample is the 841 people who responded.
D. The sample is the people in the particular country who did not respond.
(b) What is the population for this survey?
A. The population is the 841 people who responded.
B. The population is the 2 % who reported having only 1 good friend.
C. The population is all of the people in the world.
D. The population is the public in the particular country.
(c) What is the statistic reported for this survey?
A. The statistic reported is the number of good friends.
B. The statistic reported is the percentage of respondents who reported having more than 1 good friend.
C. The statistic reported is the number of people who responded 841. D. The statistic reported is the percentage of respondents who reported having only 1 good friend (2%). 3. A government agency uses a few new jeeps of each model every year to collect data on pollution emission and gasoline mileage performance. For the model A , identify what is meant by (a) subject, (b) sample, and (c) population.
(a) What is the subject of the study conducted by the government agency?
A. jeeps
B. the model A jeeps
C. the new model A jeeps
D. new jeeps
(b) What is the sample used by the government agency?
A. the few new model A jeeps that were chosen for the study
B. model A jeeps
C. jeeps
D. all new model A jeeps
(c) What is the population for the government?
A. all new jeeps
B. all new motor vehicles
C. all new model A jeeps
D. the few new model A jeeps that were chosen for the study
4. A medical study in one particular medical school conducted an experiment with 22,000 male physicians to investigate whether regular intake of a new drug reduces the chance of heart attack compared to taking calcium. The study concluded that for all male physicians, the new drug would be more effective than calcium. Identify (a) the sample, (b) the population, and (c) the inference.
(a) What is the sample for this study?
A. The sample is all of the male physicians who participated in the study.
B. The sample is all of the female physicians who participated in the study.
C. The sample is all of the physicians who study at this school.
D. The sample is all male and female physicians.
(b) What is the population for this study?
A. The population is all of the physicians who study at this school.
B. The population is all female physicians.
C. The population is all male and female physicians.
D. The population is all male physicians.
(c) What inference is drawn?
A. The inference is that the new drug would be more effective than calcium for all male physicians.
B. The inference is that the new drug would be more effective than calcium for all physicians from this medical school.
C. The inference is that the new drug and calcium would have the same effectiveness for all female physicians.
D. The inference is that calcium would be more effective than the new drug for all male physicians.
5. The job placement center at your school surveys 60% of all graduating seniors at the school. Their report about the survey provides numerical summaries such as the average starting salary and the percentage of students earning more than $40,000 a year.
a. Are these descriptive, or inferential, statistical analyses? Explain.
b. Are these numerical summaries better characterized as statistics or as parameters?
a. Are the statistical analyses descriptive or inferential statistics?
A. Descriptive, because they make predictions about the population.
B. Descriptive, because they summarize the data collected.
C. Inferential, because they make predictions about the population.
D. Inferential, because they summarize the data collected.
b. Are these numerical summaries better characterized as statistics or as parameters?
A. Parameters, because the analyses summarize data on a sample.
B. Statistics , because the analyses summarize data on a sample.
C. Parameters , because the analyses summarize data on a population.
D. Statistics, because the analyses summarize data on a population.
6. A historian wants to estimate the average age at marriage of men in a region in the early 19th century. Within his state's archives, he finds marriage records for the years 1800­1820, which he treats as a sample of all marriage records from the early 19th century. The average age of the men in the records is 28.3 years. Using the appropriate statistical method, he estimates that the average age of grooms in the region in the early 19th century was between 27.5 and 29.1 years.
a. Which part of this example gives a descriptive summary of the data?
b. Which part of this example draws an inference about a population?
c. To what population does the inference in part b refer?
d. The average age of the sample was 28.3 years. Is 28.3 a statistic or a parameter?
a. Which part of this example gives a descriptive summary of the data?
A. The interval of ages between 27.5 and 29.1 years
B. The number of men in the region in the early 19th century
C. The average age 28.3 years
D. The marriage records for the years 1800­1820
b. Which part of this example draws an inference about a population?
A. The marriage records for the years 1800­1820
B. The interval of ages between 27.5 and 29.1 years
C. The number of men in the region in the early 19th century
D. The average age 28.3 years
c. To what population does the inference in part b refer?
A. The men in the region at the present time
B. The men in the region in the early 19th century
C. All men
D. The men in the historian's state in the early 19th century
d. The average age, 28.3 years, is a (1) (1)
parameter.
statistic.
7. Consider the population of all students at your school. A certain proportion support gun control. Your friend randomly samples 35 students from the school, and uses the sample proportion who support gun control to predict the population proportion at the school. You take your own, separate random sample of 35 students, and find the sample proportion that supports gun control.
a. For the two studies, are the populations the same?
b. For the two studies, are the sample proportions necessarily the same?
a. For the two studies, are the populations the same?
A. No, because we know different people.
B. Yes, because each sample is randomly chosen from all students in the school.
C. No, because the people we choose are not the same.
D. Yes, because the sample sizes are the same.
b. For the two studies, are the sample proportions necessarily the same?
A. No, because the two random samples may differ by chance.
B. Yes, because the samples come from the same population.
C. Yes, because the sample sizes are the same.
D. No, because samples come from different populations.
1. 40.1
35.8
14.9
9.2
C. Hell
2. C. The sample is the 841 people who responded.
D. The population is the public in the particular country.
D. The statistic reported is the percentage of respondents who reported having only 1 good friend (2%). 3. C. the new model A jeeps
A. the few new model A jeeps that were chosen for the study
C. all new model A jeeps
4. A. The sample is all of the male physicians who participated in the study.
D. The population is all male physicians.
A. The inference is that the new drug would be more effective than calcium for all male physicians.
5. B. Descriptive, because they summarize the data collected.
B. Statistics , because the analyses summarize data on a sample.
6. C. The average age 28.3 years
B. The interval of ages between 27.5 and 29.1 years
B. The men in the region in the early 19th century
(1) statistic.
7. B. Yes, because each sample is randomly chosen from all students in the school.
A. No, because the two random samples may differ by chance.