2022 Fall Semester Exam Review Statistics

Last updated almost 2 years ago

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Library

2022 Fall Semester Exam Review Statistics

Last updated almost 2 years ago

43 questions

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The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

What percent of the dots show scores <18?

Then enter as a fraction, decimal proportion (Round to three places past the decimal) or as a percent.

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The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has a higher standard deviation?
ie. Which graph has greater variability?

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The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has a shape that is closest to being roughly symmetric?

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The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has the lowest mean?

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Find the interquartile range of the data in #10.

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(1.9) The following dotplot gives the sale prices for 40 houses in Ames, Iowa, sold during a recent month. The mean sale price was $203,388 with a standard deviation of $87,609.

Find the percentile of the house that is indicated on the dotplot. Remember percentile means the percent to the LEFT of a value.

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(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table to calculate P(popular)
If you enter your answer as a decimal or percent, round to three places first.

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(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table to calculate P(popular|4th grade)
If you enter your answer as a decimal or percent, round to three places first.

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(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table to calculate P(popular|5th grade)
If you enter your answer as a decimal or percent, round to three places first.

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(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table to calculate P(popular|6th grade)
If you enter your answer as a decimal or percent, round to three places first.

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(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table above to calculate P(5th grade or athletic)
If you enter your answer as a decimal or percent, round to three places first.

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(2.3) The principal of a high school read a study that reported a positive correlation between the number of calculators owned by high school students and their math achievement. Based on this study, he decides to buy each student at his school 2 calculators, hoping to improve their math achievement.
Explain the flaw in the principal’s reasoning.

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(2.5) The scatterplot shows the relationship between latitude and mean July temperature (in degrees Fahrenheit) for 12 cities in the United States.
The equation of the regression line relating these variables is y -hat = 106.5 − 0.782x.

Predict the mean July temperature in Fairbanks, Alaska, at latitude 65º.
How confident are you in this prediction?

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Use the information from #25:
The equation of the regression line relating these variables is
July temperature -hat = 106.5 − 0.782(degrees latitude)

Los Angeles, California, is at latitude 34º and actually has a mean July temperature of 74º.
Calculate the predicted temperature value for July.
Keep all places past the decimal point, no units.

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Use the information from #25:
The equation of the regression line relating these variables is
July temperature -hat = 106.5 − 0.782(degrees latitude)

Los Angeles, California, is at latitude 34º and actually has a mean July temperature of 74º.

Calculate the residual for the July prediction. Keep all decimal points, no units.

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(3.3) Is flipping a flying disk as fair as flipping a coin? Hailey flips a disk 40 times and it lands right side up only 16 times. She suspects that the disk is more likely to land upside down. To determine if these data provide convincing evidence in support of Hailey’s conclusion, 100 trials of a simulation were conducted.
Each dot in the graph shows the number of right-side-up flips in a random sample of 40 flips, assuming that each flip has a 50% chance of landing right-side up.

Explain how the graph illustrates the concept of sampling variability.
Based on the results of the simulation, is there convincing evidence that flying disks are more likely to land upside down? Explain.

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Here is some information about the first 10 U.S. presidents. Identify the individuals and variables in this data set. Classify each variable as categorical or quantitative.

State of Birth
Political Party
Name
Age at Inauguration
Age at Death

Categorical Variable
Quantitative Variable

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

What does one dot represent?

The class average score out of 21 students.

The answer to one of the questions on the 20 point quiz.

One person's score out of 20 points.

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

What percent of the dots show scores <18?

Then enter as a fraction, decimal proportion (Round to three places past the decimal) or as a percent.

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

a) Describe the shape of the distribution.
b) How does the mean compare to the median?

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

a) Using the dot plot above, what is the appropriate measure of center and spread?
b) Why would you choose these?

mean & standard deviation

the mean & Std Dev are resistant to the skew & outliers, they don't get pulled to the left.

mean & IQR

median & IQR

the skew pulls the mean to the right

the median & IQR are resistant to the skew & outliers, they don't get pulled to the left.

the skew pulls the mean to the left

median & standard deviation

Do you “binge-watch” television series by viewing multiple episodes of a series at one sitting? A survey of 800 people who “binge-watch” were asked how many episodes is too many to watch in one viewing session.
The results are displayed in the bar chart.

Explain how this graph is misleading.

The scale on the y axis causes the reader to think '5 to 6' is about 10x more frequent than '3 to 4'.

The 'there is no too many' should be listed first since it doesn't include a number.

All the colors make it confusing to read.

The scale on the y axis causes the reader to think that the 'there is no too many' is half as frequent as the '5 to 6' column.

The graph is not misleading at all.

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has a higher standard deviation?
ie. Which graph has greater variability?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has a shape that is closest to being roughly symmetric?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has the lowest mean?

For a project in their statistics class, Alex and Tempe studied the impact of different types of background music on students’ ability to remember words from a list they were allowed to study for 5 min. Here is a list of how many words one group of students who listened to Beethoven’s Fifth Symphony were able to remember.
11   12   23   15   14   15   14   15
10   14   15   9   11   13   25   11
13   13   12   20   17   23   11   12
12   11   20   20   12   12   19   13
15   10   14   11   7   17   13   18

Use statsmedic.com/applets, 1 quantitative variable. Make a histogram that effectively displays the distribution of words recalled.
Describe the histogram using D.O.F.S.

We used technology to compute the mean and median of this distribution.
One is 13 and the other is 14.3.
Based on the histogram, explain how you know which is which without doing any calculations.

The median is 13 and the mean is 14.3 because the outliers pull the mean higher.

The median is 13 and the mean is 14.3 because the outliers pull the mean lower.

The mean is 13 and the median is 14.3 because the outliers pull the mean lower.

The mean is 13 and the median is 14.3 because the outliers pull the mean higher.

Using the same histogram from #10, what effect would removing the outliers have on the mean & standard deviation?

The mean would decrease and the standard deviation would decrease.

The mean would increase and the standard deviation would decrease.

The mean would decrease and the standard deviation would increase.

The mean would increase and the standard deviation would increase.

Find the interquartile range of the data in #10.

The standard deviation is 4.05. Interpret this value in context.

The data values are 4.05 above the minimum.

The data values are typically 4.05 apart from each other.

The data values are 4.05 from the maximum.

The data values are typically 4.05 from the mean.

Catherine and Ana suspect that athletes (i.e., students who have been on at least one varsity team) typically have a faster reaction time than other students. To test this theory, they gave an online reflex test to 33 varsity athletes at their school and 30 other students. The following parallel boxplots display the reaction times (in milliseconds) for the two groups of students.

What do the data suggest about Catherine and Ana’s suspicion? Explain.

Roughly the fastest 50% of the Varsity athletes are faster than the slowest 75% of the other students.

The median reaction time for the Varsity athletes is faster than for the other students.

The Q3 for the other students is faster than the Varsity athletes.

There are two other students that have slower reaction times than all the Varsity athletes.

The Varsity athlete data has more variability than for the other students.

(1.9) The following dotplot gives the sale prices for 40 houses in Ames, Iowa, sold during a recent month. The mean sale price was $203,388 with a standard deviation of $87,609.

Find the percentile of the house that is indicated on the dotplot. Remember percentile means the percent to the LEFT of a value.

(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table to calculate P(popular)
If you enter your answer as a decimal or percent, round to three places first.

(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table to calculate P(popular|4th grade)
If you enter your answer as a decimal or percent, round to three places first.

(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table to calculate P(popular|5th grade)
If you enter your answer as a decimal or percent, round to three places first.

(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table to calculate P(popular|6th grade)
If you enter your answer as a decimal or percent, round to three places first.

Based on your previous four answers, are being popular and grade level independent?
What relationship exists if there is one?

5th graders tend to have a higher percent that want to be popular.

6th graders tend to have a higher percent that want to be popular.

Grade level does not impact or influence the percentage that want to be popular.

Being popular and grade level are independent,

Being popular and grade level are not independent,

because the percents are not similar.

4th graders tend to have a higher percent that want to be popular.

because the percents are similar.

(2.1) Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked if good grades, athletic ability, or being popular was most important to them. The two-way table summarizes the survey data.

Use the table above to calculate P(5th grade or athletic)
If you enter your answer as a decimal or percent, round to three places first.

(2.2, 2.3) At what age do babies learn to crawl? Does it take longer to learn in the winter, when babies are often bundled in clothes that restrict movement? There might even be an association between babies’ crawling age and the average temperature during the month when they first try to crawl (around 6 months after birth).
Data were collected from parents who reported the birth month and the age at which their child was first able to creep or crawl a distance of 4 feet within 1 minute. Information was obtained on 414 infants, 208 boys and 206 girls.
Average crawling age is given in weeks, and the average temperature (in degrees Fahrenheit) is for the month that is 6 months after the birth month.

Work with a partner, use statsmedic.com to make a scatterplot to display the relationship between average 6-month temperature and average crawling age. Use 2 quantitative variables.

Describe the relationship shown in the scatterplot.
Select all that apply.
If you're not sure of the strength, calculate the correlation.

What does a correlation coefficient tell us?

The direction only of a relationship.

The strength and direction of a linear relationship.

The strength only of a relationship.

The strength, direction and form of  relationship.

How would the correlation value change if the age of crawling was entered in days?

It is difficult to determine what the affect would be.

The correlation (r) value would not change.

The correlation (r) would get weaker.

The correlation (r) would get stronger.

Using your scatterplot from #25:

a) Describe what is unusual about the point representing May.

b) How does the point representing May affect the equation of the least-squares regression line? Explain.

the y-intercept to be lower.

The point representing May causes the slope to be more negative and

The point representing May is not an outlier, it's not too far out of the pattern of the data.

The point representing May causes the slope to be less negative and

The point representing May is an outlier, it is outside the pattern of the data.

the y-intercept to be higher.

Using your scatterplot from #25, if the point representing May was removed, how would that affect the equation of the least-squares regression line? Explain.

If the point representing May was removed the slope of the regression equation would become less negative and

If the point representing May was removed the slope of the regression equation would become more negative and

the y-intercept would become larger.

the y-intercept would become smaller.

If the point representing May was removed the slope of the regression equation would not change and

(2.3) The principal of a high school read a study that reported a positive correlation between the number of calculators owned by high school students and their math achievement. Based on this study, he decides to buy each student at his school 2 calculators, hoping to improve their math achievement.
Explain the flaw in the principal’s reasoning.

(2.5) The scatterplot shows the relationship between latitude and mean July temperature (in degrees Fahrenheit) for 12 cities in the United States.
The equation of the regression line relating these variables is y -hat = 106.5 − 0.782x.

Predict the mean July temperature in Fairbanks, Alaska, at latitude 65º.
How confident are you in this prediction?

Use the information from #25:
The equation of the regression line relating these variables is
July temperature -hat = 106.5 − 0.782(degrees latitude)

Los Angeles, California, is at latitude 34º and actually has a mean July temperature of 74º.
Calculate the predicted temperature value for July.
Keep all places past the decimal point, no units.

Use the information from #25:
The equation of the regression line relating these variables is
July temperature -hat = 106.5 − 0.782(degrees latitude)

Los Angeles, California, is at latitude 34º and actually has a mean July temperature of 74º.

Calculate the residual for the July prediction. Keep all decimal points, no units.

Use the information from #33:
Interpret the slope of the regression line.

For every degree increase in latitude the temperature goes up 0.782 degrees

For every degree increase in latitude the temperature goes down 0.782 degrees

For every temperature decrease in degree the latitude goes down 0.782 degrees

For every temperature increase in degree the latitude goes up 0.782 degrees

Use the information from #33:
Does the value of the y intercept have meaning in this context?
If so, interpret the y intercept. If not, explain why.

it is the temperature when the latitude is zero, at the equator.

The y intercept does not have meaning in this context

it is the latitude when the temperature is zero, at the north pole.

The y intercept has meaning in this context

We used a least-squares regression line to model the relationship between x = latitude
and y = mean July temperature (in degrees Fahrenheit) for a sample of 12 cities in the United States. Here is the residual plot for this model.

Explain what the residual plot suggests about the appropriateness of the linear model.

this indicates that the linear model is appropriate.

this indicates that the linear model is not appropriate.

The residual plot shows a strong pattern,

The residual plot shows random scatter,

(3.1) Indicate the following is a valid statistical question. Explain your reasoning.

'How many people visited Acadia National Park last Tuesday?'

the answer does not give varied answers.

Valid statistical question

Not a valid statistical question

the answer gives varied answers.

(3.1) Indicate if the following is a valid statistical question. Explain your reasoning.

'How many people visit Acadia National Park on a typical weekday in August?'

Not a valid statistical question

it gives answers that are varied.

it does not give answers that are varied.

Valid statistical question

(3.1) Indicate if the following is a valid statistical question. Explain your reasoning.

What proportion of soda bottles produced by a particular manufacturer on different days contain less soda than the label on the bottle indicates?'

it does not give answers that vary.

it gives answers that vary.

Valid statistical question

Not a valid statistical question

(3.1, 3.3, 3.4) A recent random sample of n = 805 adult U.S. residents found that the proportion who rated the honesty and ethical standards of nurses as very high or high is 0.85. This is 0.15 higher than the proportion recorded for doctors, the next highest-ranked profession.

Identify the sample and the population in this setting.

the sample is 0.85 U.S. residents.

the sample is 805 adult U.S. residents.

The population is 805 U.S. residents and

The population is all U.S. residents and

the sample is U.S. residents.

Use #40:
Do you think that the proportion of all U.S. residents who rate the honesty and ethical standards of nurses as very high or high is exactly 0.85? Explain.

No, the proportion of all U.S. residents who rate the honesty and ethical standards of nurses as very high or high is not exactly 0.85 but it is close.

This cannot be determined without doing a very large randomized study.

Yes, the proportion of all U.S. residents who rate the honesty and ethical standards of nurses as very high or high is exactly 0.85.

Use #40:
If the size of a sample in the poll was increased to 1600 residents, what effect would this have on the variability? Explain.

The variability would not change because

the sample size increased.

the sample size decreased.

the sample size did not change.

The variability would increase because

The variability would decrease because

(3.2, 3.3) The administration at a high school with 1800 students wants to gather student opinion about parking for students on campus. It isn’t practical to contact all students.

Number all students in the school, use a random number generator to draw 50 numbers, survey those corresponding students.
Stand at the doors to the courtyard and by the bus drop off and survey students as they enter the school.
Send an email to all the students and ask them to fill out the survey online.

Voluntary Response Sample
Convenience Sample
Simple Random Sample (SRS)

(3.3) Is flipping a flying disk as fair as flipping a coin? Hailey flips a disk 40 times and it lands right side up only 16 times. She suspects that the disk is more likely to land upside down. To determine if these data provide convincing evidence in support of Hailey’s conclusion, 100 trials of a simulation were conducted.
Each dot in the graph shows the number of right-side-up flips in a random sample of 40 flips, assuming that each flip has a 50% chance of landing right-side up.

Explain how the graph illustrates the concept of sampling variability.
Based on the results of the simulation, is there convincing evidence that flying disks are more likely to land upside down? Explain.

(3.5) An opinion poll calls 2000 randomly chosen residential telephone numbers, then asks to speak with an adult member of the household.
The interviewer asks, “Box-office revenues are at an all-time high. How many movies have you watched in a movie theater in the past 12 months?”
In all, 1131 people responded. The researchers used the responses to estimate the mean number of movies adults have watched in a movie theater in the past 12 months.

Categorize the types of bias with the descriptions.

Wording of the question could cause people to be more likely to respond favorable
Using only residential phone numbers to contact the sample to be surveyed
2000 Randomly chosen phone numbers were called, response from 1131 people were received.

Response Bias
Undercoverage Bias
Nonresponse Bias

Here is some information about the first 10 U.S. presidents. Identify the individuals and variables in this data set. Classify each variable as categorical or quantitative.

State of Birth

Political Party

Name

Age at Inauguration

Age at Death

Categorical Variable

Quantitative Variable

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

What does one dot represent?

The class average score out of 21 students.

The answer to one of the questions on the 20 point quiz.

One person's score out of 20 points.

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

a) Describe the shape of the distribution.
b) How does the mean compare to the median?

Skewed left

Skewed right

mean > median

mean < median

mean = median

Roughly symmetric

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

a) Using the dot plot above, what is the appropriate measure of center and spread?
b) Why would you choose these?

mean & standard deviation

the mean & Std Dev are resistant to the skew & outliers, they don't get pulled to the left.

mean & IQR

median & IQR

the skew pulls the mean to the right

the median & IQR are resistant to the skew & outliers, they don't get pulled to the left.

the skew pulls the mean to the left

median & standard deviation

Do you “binge-watch” television series by viewing multiple episodes of a series at one sitting? A survey of 800 people who “binge-watch” were asked how many episodes is too many to watch in one viewing session. 
The results are displayed in the bar chart. 


Explain how this graph is misleading.

The scale on the y axis causes the reader to think '5 to 6' is about 10x more frequent than '3 to 4'.

The 'there is no too many' should be listed first since it doesn't include a number.

All the colors make it confusing to read.

The scale on the y axis causes the reader to think that the 'there is no too many' is half as frequent as the '5 to 6' column.

The graph is not misleading at all.

For a project in their statistics class, Alex and Tempe studied the impact of different types of background music on students’ ability to remember words from a list they were allowed to study for 5 min. Here is a list of how many words one group of students who listened to Beethoven’s Fifth Symphony were able to remember.
11   12   23   15   14   15   14   15
10   14   15   9   11   13   25   11
13   13   12   20   17   23   11   12
12   11   20   20   12   12   19   13
15   10   14   11   7   17   13   18

Use statsmedic.com/applets, 1 quantitative variable. Make a histogram that effectively displays the distribution of words recalled.
Describe the histogram using D.O.F.S.

Center about 11 or 12

Right skewed

Roughly symmetric

There are outliers to the right

There are outliers to the left

There are no outliers

Left skewed

Range of about 16

Center about 15

Range of about 18

We used technology to compute the mean and median of this distribution. 
One is 13 and the other is 14.3. 
Based on the histogram, explain how you know which is which without doing any calculations.

The median is 13 and the mean is 14.3 because the outliers pull the mean higher.

The median is 13 and the mean is 14.3 because the outliers pull the mean lower.

The mean is 13 and the median is 14.3 because the outliers pull the mean lower.

The mean is 13 and the median is 14.3 because the outliers pull the mean higher.

Using the same histogram from #10, what effect would removing the outliers have on the mean & standard deviation?

The mean would decrease and the standard deviation would decrease.

The mean would increase and the standard deviation would decrease.

The mean would decrease and the standard deviation would increase.

The mean would increase and the standard deviation would increase.

The standard deviation is 4.05. Interpret this value in context.

The data values are 4.05 above the minimum.

The data values are typically 4.05 apart from each other.

The data values are 4.05 from the maximum.

The data values are typically 4.05 from the mean.

Catherine and Ana suspect that athletes (i.e., students who have been on at least one varsity team) typically have a faster reaction time than other students. To test this theory, they gave an online reflex test to 33 varsity athletes at their school and 30 other students. The following parallel boxplots display the reaction times (in milliseconds) for the two groups of students. 

What do the data suggest about Catherine and Ana’s suspicion? Explain.

Roughly the fastest 50% of the Varsity athletes are faster than the slowest 75% of the other students.

The median reaction time for the Varsity athletes is faster than for the other students.

The Q3 for the other students is faster than the Varsity athletes.

There are two other students that have slower reaction times than all the Varsity athletes.

The Varsity athlete data has more variability than for the other students.

Based on your previous four answers, are being popular and grade level independent?
What relationship exists if there is one?

5th graders tend to have a higher percent that want to be popular.

6th graders tend to have a higher percent that want to be popular.

Grade level does not impact or influence the percentage that want to be popular.

Being popular and grade level are independent,

Being popular and grade level are not independent,

because the percents are not similar.

4th graders tend to have a higher percent that want to be popular.

because the percents are similar.

(2.2, 2.3) At what age do babies learn to crawl? Does it take longer to learn in the winter, when babies are often bundled in clothes that restrict movement? There might even be an association between babies’ crawling age and the average temperature during the month when they first try to crawl (around 6 months after birth). 
Data were collected from parents who reported the birth month and the age at which their child was first able to creep or crawl a distance of 4 feet within 1 minute. Information was obtained on 414 infants, 208 boys and 206 girls. 
Average crawling age is given in weeks, and the average temperature (in degrees Fahrenheit) is for the month that is 6 months after the birth month.


Work with a partner, use statsmedic.com to make a scatterplot to display the relationship between average 6-month temperature and average crawling age. Use 2 quantitative variables.

Describe the relationship shown in the scatterplot.
Select all that apply.
If you're not sure of the strength, calculate the correlation.

Negative

Positive

No direction

linear

nonlinear

moderate relationship

strong relationship

weak relationship

What does a correlation coefficient tell us?

The direction only of a relationship.

The strength and direction of a linear relationship.

The strength only of a relationship.

The strength, direction and form of  relationship.

How would the correlation value change if the age of crawling was entered in days?

It is difficult to determine what the affect would be.

The correlation (r) value would not change.

The correlation (r) would get weaker.

The correlation (r) would get stronger.

Using your scatterplot from #25:

a)  Describe what is unusual about the point representing May.

b) How does the point representing May affect the equation of the least-squares regression line? Explain.

the y-intercept to be lower.

The point representing May causes the slope to be more negative and

The point representing May is not an outlier, it's not too far out of the pattern of the data.

The point representing May causes the slope to be less negative and

The point representing May is an outlier, it is outside the pattern of the data.

the y-intercept to be higher.

Using your scatterplot from #25, if the point representing May was removed, how would that affect the equation of the least-squares regression line? Explain.

If the point representing May was removed the slope of the regression equation would become less negative and

If the point representing May was removed the slope of the regression equation would become more negative and

the y-intercept would become larger.

the y-intercept would become smaller.

If the point representing May was removed the slope of the regression equation would not change and

Use the information from #33:
Interpret the slope of the regression line.

For every degree increase in latitude the temperature goes up 0.782 degrees

For every degree increase in latitude the temperature goes down 0.782 degrees

For every temperature decrease in degree the latitude goes down 0.782 degrees

For every temperature increase in degree the latitude goes up 0.782 degrees

Use the information from #33:
Does the value of the y intercept have meaning in this context? 
If so, interpret the y intercept. If not, explain why.

it is the temperature when the latitude is zero, at the equator.

The y intercept does not have meaning in this context

it is the latitude when the temperature is zero, at the north pole.

The y intercept has meaning in this context

We used a least-squares regression line to model the relationship between x = latitude 
and y = mean July temperature (in degrees Fahrenheit) for a sample of 12 cities in the United States. Here is the residual plot for this model.


Explain what the residual plot suggests about the appropriateness of the linear model.

this indicates that the linear model is appropriate.

this indicates that the linear model is not appropriate.

The residual plot shows a strong pattern,

The residual plot shows random scatter,

(3.1) Indicate the following is a valid statistical question. Explain your reasoning.

'How many people visited Acadia National Park last Tuesday?'

the answer does not give varied answers.

Valid statistical question

Not a valid statistical question

the answer gives varied answers.

(3.1) Indicate if the following is a valid statistical question. Explain your reasoning.

'How many people visit Acadia National Park on a typical weekday in August?'

Not a valid statistical question

it gives answers that are varied.

it does not give answers that are varied.

Valid statistical question

(3.1) Indicate if the following is a valid statistical question. Explain your reasoning.

What proportion of soda bottles produced by a particular manufacturer on different days contain less soda than the label on the bottle indicates?'

it does not give answers that vary.

it gives answers that vary.

Valid statistical question

Not a valid statistical question

(3.1, 3.3, 3.4) A recent random sample of n = 805 adult U.S. residents found that the proportion who rated the honesty and ethical standards of nurses as very high or high is 0.85. This is 0.15 higher than the proportion recorded for doctors, the next highest-ranked profession.

Identify the sample and the population in this setting.

the sample is 0.85 U.S. residents.

the sample is 805 adult U.S. residents.

The population is 805 U.S. residents and

The population is all U.S. residents and

the sample is U.S. residents.

Use #40:
Do you think that the proportion of all U.S. residents who rate the honesty and ethical standards of nurses as very high or high is exactly 0.85? Explain.

No, the proportion of all U.S. residents who rate the honesty and ethical standards of nurses as very high or high is not exactly 0.85 but it is close.

This cannot be determined without doing a very large randomized study.

Yes, the proportion of all U.S. residents who rate the honesty and ethical standards of nurses as very high or high is exactly 0.85.

Use #40:
If the size of a sample in the poll was increased to 1600 residents, what effect would this have on the variability? Explain.

The variability would not change because

the sample size increased.

the sample size decreased.

the sample size did not change.

The variability would increase because

The variability would decrease because

(3.2, 3.3) The administration at a high school with 1800 students wants to gather student opinion about parking for students on campus. It isn’t practical to contact all students.

Number all students in the school, use a random number generator to draw 50 numbers, survey those corresponding students.

Stand at the doors to the courtyard and by the bus drop off and survey students as they enter the school.

Send an email to all the students and ask them to fill out the survey online.

Voluntary Response Sample

Convenience Sample

Simple Random Sample (SRS)

(3.5) An opinion poll calls 2000 randomly chosen residential telephone numbers, then asks to speak with an adult member of the household. 
The interviewer asks, “Box-office revenues are at an all-time high. How many movies have you watched in a movie theater in the past 12 months?” 
In all, 1131 people responded. The researchers used the responses to estimate the mean number of movies adults have watched in a movie theater in the past 12 months.

Categorize the types of bias with the descriptions.

Wording of the question could cause people to be more likely to respond favorable

Using only residential phone numbers to contact the sample to be surveyed

2000 Randomly chosen phone numbers were called, response from 1131 people were received.

Response Bias

Undercoverage Bias

Nonresponse Bias

2022 Fall Semester Exam Review Statistics

2022 Fall Semester Exam Review Statistics

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.What percent of the dots show scores <18?Then enter as a fraction, decimal proportion (Round to three places past the decimal) or as a percent.

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data. Which graph has a higher standard deviation?ie. Which graph has greater variability?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data. Which graph has a shape that is closest to being roughly symmetric?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data. Which graph has the lowest mean?

Find the interquartile range of the data in #10.

Here is some information about the first 10 U.S. presidents. Identify the individuals and variables in this data set. Classify each variable as categorical or quantitative.

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.What does one dot represent?

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.What percent of the dots show scores <18?Then enter as a fraction, decimal proportion (Round to three places past the decimal) or as a percent.

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.a) Describe the shape of the distribution.b) How does the mean compare to the median?

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.a) Using the dot plot above, what is the appropriate measure of center and spread?b) Why would you choose these?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data. Which graph has a higher standard deviation?ie. Which graph has greater variability?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data. Which graph has a shape that is closest to being roughly symmetric?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data. Which graph has the lowest mean?

We used technology to compute the mean and median of this distribution. One is 13 and the other is 14.3. Based on the histogram, explain how you know which is which without doing any calculations.

Using the same histogram from #10, what effect would removing the outliers have on the mean & standard deviation?

Find the interquartile range of the data in #10.

The standard deviation is 4.05. Interpret this value in context.

Based on your previous four answers, are being popular and grade level independent?What relationship exists if there is one?

What does a correlation coefficient tell us?

How would the correlation value change if the age of crawling was entered in days?

Using your scatterplot from #25:a) Describe what is unusual about the point representing May.b) How does the point representing May affect the equation of the least-squares regression line? Explain.

Using your scatterplot from #25, if the point representing May was removed, how would that affect the equation of the least-squares regression line? Explain.

Use the information from #33:Interpret the slope of the regression line.

Use the information from #33:Does the value of the y intercept have meaning in this context? If so, interpret the y intercept. If not, explain why.

(3.1) Indicate the following is a valid statistical question. Explain your reasoning.'How many people visited Acadia National Park last Tuesday?'

(3.1) Indicate if the following is a valid statistical question. Explain your reasoning.'How many people visit Acadia National Park on a typical weekday in August?'

(3.1) Indicate if the following is a valid statistical question. Explain your reasoning.What proportion of soda bottles produced by a particular manufacturer on different days contain less soda than the label on the bottle indicates?'

Use #40:Do you think that the proportion of all U.S. residents who rate the honesty and ethical standards of nurses as very high or high is exactly 0.85? Explain.

Use #40:If the size of a sample in the poll was increased to 1600 residents, what effect would this have on the variability? Explain.

(3.2, 3.3) The administration at a high school with 1800 students wants to gather student opinion about parking for students on campus. It isn’t practical to contact all students.

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

What percent of the dots show scores <18?

Then enter as a fraction, decimal proportion (Round to three places past the decimal) or as a percent.

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has a higher standard deviation?
ie. Which graph has greater variability?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has a shape that is closest to being roughly symmetric?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has the lowest mean?

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

What does one dot represent?

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

What percent of the dots show scores <18?

Then enter as a fraction, decimal proportion (Round to three places past the decimal) or as a percent.

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

a) Describe the shape of the distribution.
b) How does the mean compare to the median?

The dotplot below displays shows the scores of 21 Statistics students on a 20-point quiz.

a) Using the dot plot above, what is the appropriate measure of center and spread?
b) Why would you choose these?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has a higher standard deviation?
ie. Which graph has greater variability?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has a shape that is closest to being roughly symmetric?

The dotplots show the total family income of 40 randomly chosen individuals each from Connecticut, Indiana, and Maine, based on U.S. Census data.

Which graph has the lowest mean?

We used technology to compute the mean and median of this distribution.
One is 13 and the other is 14.3.
Based on the histogram, explain how you know which is which without doing any calculations.

Based on your previous four answers, are being popular and grade level independent?
What relationship exists if there is one?

Using your scatterplot from #25:

a) Describe what is unusual about the point representing May.

b) How does the point representing May affect the equation of the least-squares regression line? Explain.

Use the information from #33:
Interpret the slope of the regression line.

Use the information from #33:
Does the value of the y intercept have meaning in this context?
If so, interpret the y intercept. If not, explain why.

(3.1) Indicate the following is a valid statistical question. Explain your reasoning.

'How many people visited Acadia National Park last Tuesday?'

(3.1) Indicate if the following is a valid statistical question. Explain your reasoning.

'How many people visit Acadia National Park on a typical weekday in August?'

(3.1) Indicate if the following is a valid statistical question. Explain your reasoning.

What proportion of soda bottles produced by a particular manufacturer on different days contain less soda than the label on the bottle indicates?'

Use #40:
Do you think that the proportion of all U.S. residents who rate the honesty and ethical standards of nurses as very high or high is exactly 0.85? Explain.

Use #40:
If the size of a sample in the poll was increased to 1600 residents, what effect would this have on the variability? Explain.