STATS - Midterm Review

How many pets do you have? What kind of data would the results from this question produce?

Quantitative Data

What is data that is collected in groups or topics, where the number of events in each group is counted numerically?

Quantitative data

A student plans to see a movie this weekend. Based on these movies, how long would a typical movie be expected to​ run? The accompanying histogram shows the running times in minutes of the 150​ top-grossing feature films released in a certain year.

about 105 minutes

The grades on the midterm at Springer are roughly symmetric with m=73 and o=3.0. Umaima scored a 72 on the exam Find the z-score on Uma's exam. Round to 2 decimal places

-0.33

On one test your class achieved an average grade of 75 with a standard deviation of 5 points. If you got a 91, what is your z-score?

-3.2

Danila breeds peregrine falcons. She recorded the breath (in mm) of each egg and the mass (in g) of the falcon chick that it hatched from. y = -47x + 2x What is the residual of a 29g falcon chick who hatches from an egg with a breadth of 44mm

-4g

The notation a ≥ b or a ⩾ b means that a is greater than or equal to b (or, equivalently, at least b, or not less than b). Below is a histogram of the heights of all of Major League Baseballs pitches at the start of the 2017 season. The mean height of the pitches is 74.5 inches and the standard deviation is about 2.1 inches. What proportion of baseball pitches should we expect to be at least 78 inches tall?

0.047

Find the shaded area of normal model

0.252

The normal model shown shows the shaded region between z= -0.5 and z=1.0 Determine the shaded area

0.52

How many rocks are in Nija's collection

10

Here's a box plot that summarizes the number of pencils in each student's desk. Find the range of the data.

12 pencils

The table shows the number of laps each person walked for a charity event. Find the median number of laps.

14.5

The lifespan of gorillas in a particular zoo is normally distributed. The average gorilla lives 16 years; the standard deviation is 1.7 years. Use the empirical rule (68-95-99.7) to estimate the probability of a gorilla living less than 14.3 years

16%

According to the 1.5xIQR rule for outliers, how many HIGH OUTLIERS are there in the data set?

2

How many more pumpkins have mass between 9 and 12kg than between 0 and 3kg

2

The lifespan of meerkats in a particular zoo are normally distributed. Use the empirical rule (68-95-99.7) to estimate the probability of a meerkat living between 16.1 and 17.6 years.

2.35%

Find the interquartile range (IQR) of the data set. The following data points represent the number of hours each of the staff members at Daniel's Department Store slept Thanksgiving night.

3

Which of the scatterplots shows a very strong association?

3

Here's a box plot that summarizes Julia's number of rebounds in the basketball games she played this season. Find the IQR of the data.

3 rebounds

Joe sells used cars y = 11,000 + 18,000x What is the residual of a car that is 2 years old and has been driven 50,000km

3000

Ricardo works in the marketing department of a design company. What is the minimum number of games they must sell in August to earn the bonus.

5882

Here's a box plot that summarizes the average monthly rainfall of several cities. Find the median of the data

6

IQ score have a bell-shaped distribution with a mean of 100 and a standard deviation of 15. What percentage of IQ scores are between 70 and 130? Remark: use Empirical Rule

95%

Which line fits the data graphed below?

A

Marine biologists are concerned that pollution from a nearby factory has affected the health of local sea urchins. Which of the following is most likely to be the population of​ interest?

All of the sea urchins near the plant

Camille is comparing different apartment complexes. Here is the data she collected. Who are the individuals in this data set?

Apartment complexes

Describe the overall shapes of these distributions. A National Vital Statistics Report provides information on deaths by​ age, sex, and race. Below is a link to the displays of the distributions of ages at death for White and Black males. Use these displays to complete parts a through c below.

Both distributions are left-skewed and unimodal.

What is your favorite band? What kind of data would the results from this question produce?

Categorical Data

The graph below shows the relationship between population density (in people per square kilometer) and average rent for 1-bedroom apartments in different cities. Which statement is the best description of the association between these variables?Choose 1 answer.

Cities with higher population densities tended to have higher rents

Irene is gathering information about students at a local college. Here is some of the data she collected. Who are the individuals in this data set?

College students

The graph below shows the relationship between life expectancy and infant mortality rate in a random sample of countries.Which statement is the best description of the association between these variables?Choose 1 answer.

Countries with higher infant mortality rates tended to have shorter life expectancies

Which of the following variables is most likely to be used as quantitative?

Flash drive capacity

Which of the following variables is most likely to be used as categorical?

Flower color

Nate wants to predict how much people use the Internet each day based on their age. The graph below shows the age (in years) and average daily internet usage (in hours) for a sample of people. Which statement is the best description of the association between these variables?

Internet use was highest for those between 20 and 35 years old

What are the values of the mean and standard deviation of the Standard Normal Model?

Mean=0 and SD=1

The graph shown below shows the relationship between the age of drivers and the number of car accidents per 100 drivers in the year 2009. What is the best description of this relationship?

Negative linear correlation

Dexter's class recorded data on the test grades and shoe sizes of students in the class. The data is shown in the scatterplot below. What is the best description of the relationship between shoe size and test scores?

No association

Which of the scatterplots shows a negative association?

None of these scatterplotts

Abigail gathered data on different schools' winning percentages and the average yearly salary of their head coaches (in millions of dollars) in the years 2000-2011. She then created the following scatterplot and regression line. The fitted line has a slope of 8.42.What is the best interpretation of this slope?

On average, each 1 million dollar increase in salary was associated with an 8.42-point increase in winning percentage

Sam measured the height and petal length (in centimeters) of all the flowers in his garden. What is the best description of the relationship between height and petal length for Sam's flowers?

Positive association

What kind of distribution does the picture show?

Skewed to the right

Explain how you could​ tell, by looking at a​ boxplot, where the tallest bars on the histogram would be located.

The areas in the boxplot where two vertical dividers are closest together will likely contain the tallest bars.

How do the distributions differ? A National Vital Statistics Report provides information on deaths by​ age, sex, and race. Below is a link to the displays of the distributions of ages at death for White and Black males.

The center for the distribution of Black males is less than the center of the distribution of White males

Describe the spread. Write a brief description of the distribution of the pizza slice prices seen in the histogram.

The cost was between $2.4 and $3.4, never getting cheaper than $2.4 and only rarely going above $3.2

Describe the center. Write a brief description of the distribution of the pizza slice prices seen in the histogram.

The distribution of pizza prices is centered around $2.8 per slice (Correct answer, Your answer)

Describe the Shape. Write a brief description of the distribution of the pizza slice prices seen in the histogram.

The distribution of pizza prices is unimodal and roughly symmetric.

Breakfast cereals Potassium = 38 + 27fiber

The potassium content is actually lower than the model predicts for a cereal with that much fiber.

A bus company wanted to know if the number of complaints they received was a function of the number of buses it ran. The company carried out a study comparing the average number of buses per hour for different days and the number of complaints that it received on those days. The results are shown in the graph below. Which statement is the best description of the association between these variables?

There tended to be fewer complaints on days with more buses.

Based on data collected over several​ sessions, a statistically minded trainer of office typists modeled the linear relationship between the number of hours of training a typist receives​ (assuming that all typists have received at least some​ training) and the​ typist's speed​ (in words per​ minute) with the equation below. Which is the best interpretation of the​ y-intercept for this​ model?

The​ y-intercept is meaningless here because none of the typists had 0 hours of training.

Interpret the residual for the bunch indicated in the scatterplot. Caden tracked the store life of a bunch of bananas in his store and the storage temperature of the area where he displayed them

This bunch's storage life was 2°C fewer days than predicted based on the storage temperature.

Chloe surveyed students in her class about the numbers of text messages they sent and received the previous day. An approximate least-squares regression line was used to predict the number of text messages received from a given number of text messages sent. Interpret the residual for the student indicated in the scatterplot.

This student received 20 more text messages than predicted based on the number of text messages sent.

Below are the summary statistics for the size in acres of some local vineyards. Are any of the vineyards outliers?

Yes, because the maximum value is far greater than the upper fence.

Find the equation of the regression line. ​(Round to the nearest integer as needed. Do not include the​ $ symbol in your​ answers.)

price = 14,263 - 955age

What is the better value of the correlation coefficient for the scatterplot below?

r = 0.73

Jacob distributed a survey to his fellow students asking them how many hours they spent on the Internet in the past day. He also asked them to rate their mood on a scale from 0 to 10, with 10 being the happiest. A line was fit to the data to model the relationship. Which of these linear equations best describes the given model?

y = -x + 7.5

Researchers, hoping to find ways to make a good estimate of a​ person's body fat percentage without immersing him or her in water, immersed 15 male subjects and recorded their weights.

y = 0.288 + 0.187x

We wish to predict calories based on the amount of fat grams in fast-food hamburgers. Use the following data to answer the questions below. Write the equation of the line of regression. Choose the correct equation below.

y= 320.240 + 12.858

Which of the following is an example of categorical data?

zip codes of shoppers at an appliance store