STATS 107 Exam 1 Questions with Correct Answers Latest Update 2025/2026
The essential difference between an experiment and an observational study is that ... - Answers
an experiment imposes treatments on subjects, but an observational study does not
A Gallup Poll recently showed that 69% of Americans believe there is a hell. The poll contacted
1003 adults by telephone. The margin of sampling error was plus or minus three percentage
points. Assume a 95% confidence level and no bias. The sample for this poll is ... - Answers the
1003 people who answered the question
You want to know the opinions of American school teachers about establishing a national test
for high school graduation. You obtain a list of the members of the National Education
Association (The largest teacher union) and mail a questionnaire to 2500 teachers chosen at
random form this list. In all 1,347 teachers return the questionnaire.
In this situation, The population is - Answers all american school teachers
In a ____, all subjects of the population are studied - Answers census
Researchers did this study. Twenty-two students worked a paper and pencil maze six times. On
three tries, they wore a mask with floral scents. On the other three tries, they wore a mask with
no scent. The six tries were done in random order and each use a different maze. The
researchers found that the subject took less time to complete the maze when wearing the
scented mask.
This study is a(n)... - Answers experiment
We select a sample in order to - Answers get information about some population
You want a survey of college students so you select 30 students from a statistics class to rate a
new video game.
These 30 students are ... - Answers a convenience sample
You want to take an SRS of 50 of the 816 students who live in a college dormitory. You label the
students 001 to 816 in alphabetical order. In the table of random digits you read the entries
96746, 12149, 37823, 71868, 18442, 35119, 62103, 39244. The first three students in your
sample have labels... - Answers 967, 121, 378
The mayor's office wants to know how people in the city feel about the conditions of the city's
roads. They place an announcement in the newspaper asking residents to email their opinions
, to the mayor's office. Five hundred people send emails, and about 84% of the responses
indicate displeasure with the condition of the city's roads.
This is a.. - Answers This is a voluntary response sample. It will almost certainly overestimate
the level of displeasure among the city's residents.
Bias in a sampling method is .... - Answers any systematic error that tends to occur in the same
direction every time you use this sampling method
The student newspaper runs a weekly question that readers can answer online or by campus
mail. One question was "Do you think the college is doing enough to provide student parking?"
of the 82 people who responded, 79% said "No."
The number 79% is a ... - Answers statistic
The student newspaper runs a weekly question that readers can answer online or by campus
mail. One question was "Do you think the college is doing enough to provide student parking?"
of the 82 people who responded, 79% said "No."
If we applied the quick method to the poll, we would obtain this 95% confidence interval: -
Answers 79% + or - 11%
Does coaching raise SAT scores? Because many students score higher on a second try, even
without coaching, a study looked at a simple random sample of 4200 students who took the
SAT twice. Of these, 500 had taken coaching courses between their two attempts at the SAT.
The study compared the average increase in scores (out of the total possible score of 2400) for
students who were coached with the average increase of students who were not coached. The
report of the SAT study says, "With 95% confidence, we can say that students who are coached
raised their average SAT scores by between 28 and 57 points more than those who are not
coached."
By "95% confidence," we mean that.. - Answers we obtained the 28 to 57 point range by using a
method that would give the same answer in 95% of all samples
If we take many simple random samples from the same population, we expect - Answers the
values of the statistic will vary from sample to sample
If a gallup poll surveys a national sample of 3000 people rather than 1500 people, the margin of
error of the sample result would be ... - Answers less than it would be for 1500 because the
The essential difference between an experiment and an observational study is that ... - Answers
an experiment imposes treatments on subjects, but an observational study does not
A Gallup Poll recently showed that 69% of Americans believe there is a hell. The poll contacted
1003 adults by telephone. The margin of sampling error was plus or minus three percentage
points. Assume a 95% confidence level and no bias. The sample for this poll is ... - Answers the
1003 people who answered the question
You want to know the opinions of American school teachers about establishing a national test
for high school graduation. You obtain a list of the members of the National Education
Association (The largest teacher union) and mail a questionnaire to 2500 teachers chosen at
random form this list. In all 1,347 teachers return the questionnaire.
In this situation, The population is - Answers all american school teachers
In a ____, all subjects of the population are studied - Answers census
Researchers did this study. Twenty-two students worked a paper and pencil maze six times. On
three tries, they wore a mask with floral scents. On the other three tries, they wore a mask with
no scent. The six tries were done in random order and each use a different maze. The
researchers found that the subject took less time to complete the maze when wearing the
scented mask.
This study is a(n)... - Answers experiment
We select a sample in order to - Answers get information about some population
You want a survey of college students so you select 30 students from a statistics class to rate a
new video game.
These 30 students are ... - Answers a convenience sample
You want to take an SRS of 50 of the 816 students who live in a college dormitory. You label the
students 001 to 816 in alphabetical order. In the table of random digits you read the entries
96746, 12149, 37823, 71868, 18442, 35119, 62103, 39244. The first three students in your
sample have labels... - Answers 967, 121, 378
The mayor's office wants to know how people in the city feel about the conditions of the city's
roads. They place an announcement in the newspaper asking residents to email their opinions
, to the mayor's office. Five hundred people send emails, and about 84% of the responses
indicate displeasure with the condition of the city's roads.
This is a.. - Answers This is a voluntary response sample. It will almost certainly overestimate
the level of displeasure among the city's residents.
Bias in a sampling method is .... - Answers any systematic error that tends to occur in the same
direction every time you use this sampling method
The student newspaper runs a weekly question that readers can answer online or by campus
mail. One question was "Do you think the college is doing enough to provide student parking?"
of the 82 people who responded, 79% said "No."
The number 79% is a ... - Answers statistic
The student newspaper runs a weekly question that readers can answer online or by campus
mail. One question was "Do you think the college is doing enough to provide student parking?"
of the 82 people who responded, 79% said "No."
If we applied the quick method to the poll, we would obtain this 95% confidence interval: -
Answers 79% + or - 11%
Does coaching raise SAT scores? Because many students score higher on a second try, even
without coaching, a study looked at a simple random sample of 4200 students who took the
SAT twice. Of these, 500 had taken coaching courses between their two attempts at the SAT.
The study compared the average increase in scores (out of the total possible score of 2400) for
students who were coached with the average increase of students who were not coached. The
report of the SAT study says, "With 95% confidence, we can say that students who are coached
raised their average SAT scores by between 28 and 57 points more than those who are not
coached."
By "95% confidence," we mean that.. - Answers we obtained the 28 to 57 point range by using a
method that would give the same answer in 95% of all samples
If we take many simple random samples from the same population, we expect - Answers the
values of the statistic will vary from sample to sample
If a gallup poll surveys a national sample of 3000 people rather than 1500 people, the margin of
error of the sample result would be ... - Answers less than it would be for 1500 because the
