Question 1

What is statistics?

Accepted Answer

Statistics is the science of data that involves collecting, classifying, summarizing,
organizing, analyzing, and interpreting numerical information.

Question 2

When we take data obtained from a sample and make generalizations or predictions about the
entire population, we are utilizing inferential statistics.

Accepted Answer

Inferential statistics involve using data from a sample to make estimates or predictions about a larger population, allowing us to draw conclusions beyond the immediate data observed.

Question 3

Parking at a large university has become a very big problem. University administrators are interested in determining the average parking time (e.g. the time it takes a student to find a
Parking spot)of its students. An administrator inconspicuously followed 250 students and
Carefully recorded their parking times. Identify the sample of interest to the university
Administration.

Accepted Answer

The sample of interest consists of the specific group from which data was collected, in this case, the 250 students that were followed and observed by the administrator.

Question 4

The average age of the students in a statistics class is 22 years. Does this statement describe descriptive or inferential statistics?

Accepted Answer

Descriptive statistics summarize and describe the features of a data set, including measures like average age, without making predictions or generalizations about a larger population.

Question 5

As part of an economics class project, students were asked to randomly select 500 New York Stock Exchange (NYSE)stocks from the Wall Street Journal. As part of the project, students were asked
To summarize the current prices (also referred to as the closing price of the stock for a particular
Trading date)of the collected stocks using graphical and numerical techniques. Would this be an
Application of descriptive or inferential statistics?

Accepted Answer

This is an application of descriptive statistics because the students are summarizing and presenting the current prices of the selected stocks without making predictions or generalizations about the entire stock market.

Question 6

A study attempted to estimate the proportion of Florida residents who were willing to spend more tax dollars on protecting the Florida beaches from environmental disasters. Twenty-two hundred
Florida residents were surveyed.Which of the following describes the variable of interest in the
Study?

Accepted Answer

The variable of interest in the study is the response to the specific question about willingness to spend more tax dollars on protecting the Florida beaches from environmental disasters, as this directly addresses the study's goal.

Question 7

From past figures, it is predicted that 30% of the registered voters will vote in the March primary. Does this statement describe descriptive or inferential statistics?

Accepted Answer

This statement is an example of inferential statistics because it makes a prediction about a future event based on past data, rather than merely describing a set of data.

Question 8

Parking at a large university has become a very big problem. University administrators are interested in determining the average parking time (e.g. the time it takes a student to find a
Parking spot)of its students. An administrator inconspicuously followed 250 students and
Carefully recorded their parking times. The university is interested in using the information from
The sample of 250 students collected to learn information about the entire student parking
Population. Would this be an application of descriptive or inferential statistics?

Accepted Answer

Inferential statistics is used when information from a sample is used to make inferences or draw conclusions about a larger population. In this case, the university is using the sample of 250 students to learn about the parking times of the entire student population, which is an application of inferential statistics.

Question 9

Parking at a university has become a problem. University administrators are interested in determining the average time it takes a student to find a parking spot. An administrator
Inconspicuously followed 200 students and recorded how long it took each of them to find a
Parking spot. Identify the variable of interest to the university administration.

Accepted Answer

The variable of interest is the time it takes for a student to find a parking spot, as this is what the administrator recorded for each of the 200 students.

Question 10

An assembly line is operating satisfactorily if fewer than 3% of the phones produced per day are defective. To check the quality of a dayʹs production, the company randomly samples 10 phones
From a dayʹs production to test for defects. Define the population of interest to the manufacturer.

Accepted Answer

The population of interest to the manufacturer is all the phones produced during the day in question, as the goal is to assess the quality of the entire day's production, not just the sample or a specific subset.

Question 11

A survey of high school teenagers reported that 83% of those sampled are interested in pursuing a college education. Does this statement describe descriptive or inferential statistics?

Accepted Answer

The statement is describing a characteristic (interest in pursuing a college education) of a specific group (high school teenagers surveyed), which is a hallmark of descriptive statistics. It summarizes data from that sample without making predictions or generalizations about a larger population.

Question 12

A recent report stated ʺBased on a sample of 250 truck drivers, there is evidence to indicate that, on average, independent truck drivers earn more than company-hired truck drivers.ʺ Does this
Statement describe descriptive or inferential statistics?

Accepted Answer

The statement is making an inference about the population of truck drivers based on a sample, which is the essence of inferential statistics.

Question 13

Parking at a university has become a problem. University administrators are interested in determining the average time it takes a student to find a parking spot. An administrator
Inconspicuously followed 90 students and recorded how long it took each of them to find a
Parking spot. Identify the population of interest to the university administration.

Accepted Answer

The population of interest to the university administration is the entire set of students who park at the university, as they are trying to determine the average time it takes for a student to find a parking spot, implying interest in all students who park there.

Question 14

Which of the following is not an element of descriptive statistical problems?

Accepted Answer

Descriptive statistics involve summarizing and organizing data to identify patterns, but they do not involve making predictions about a larger set of data. Predictions pertain to inferential statistics, which aim to draw conclusions and make predictions about a population based on a sample.

Question 15

Parking at a large university has become a very big problem. University administrators are interested in determining the average parking time (e.g. the time it takes a student to find a
Parking spot)of its students. An administrator inconspicuously followed 250 students and
Carefully recorded their parking times. Identify the population of interest to the university
Administration.

Accepted Answer

The population of interest refers to the entire group about which the university administrators want to draw conclusions, which in this case is all students that park at the university.

Question 16

Statistics involves two different processes, describing sets of data and drawing conclusions about
the sets of data on the basis of sampling.

Accepted Answer

Statistics involves descriptive statistics, which summarize and describe the features of a dataset, and inferential statistics, which make predictions or inferences about a population based on a sample of data.

Question 17

A study attempted to estimate the proportion of Florida residents who were willing to spend more tax dollars on protecting the Florida coastline from environmental disasters. Thirty-nine hundred
Florida residents were surveyed.Which of the following is the population used in the study?

Accepted Answer

The population in the study refers to the entire group of individuals the research aims to understand or make inferences about, which in this case is all Florida residents, as the study attempted to estimate the proportion of all Florida residents willing to spend more on coastline protection.

Question 18

In a survey of 2000 high school students, 14% of those surveyed read at least one
best-seller each month. Give an example of a descriptive statement and an inferential
statement that could be made based on this information.

Accepted Answer

The answer of In a survey of 2000 high school...

Question 19

An insurance company conducted a study to determine the percentage of cardiologists who had been sued for malpractice in the previous two years. The sample was randomly chosen from a
National directory of doctors. What is the variable of interest in this study?

Accepted Answer

The variable of interest in this study is whether the cardiologists had been sued for malpractice in the previous two years, which is a categorical variable represented by the responses: have been sued/have not been sued.

Question 20

Which of the following is not the job of a statistician?

Accepted Answer

Implementing new procedures based on the results of a study is typically not the job of a statistician. Statisticians focus on designing studies, analyzing data, and interpreting results rather than implementing new procedures, which is often the role of practitioners or policymakers in the relevant field.

Quiz 1: Statistics, Data, and Statistical Thinking

What is statistics?

When we take data obtained from a sample and make generalizations or predictions about the entire population, we are utilizing inferential statistics.

The average age of the students in a statistics class is 22 years. Does this statement describe descriptive or inferential statistics?

A study attempted to estimate the proportion of Florida residents who were willing to spend more tax dollars on protecting the Florida beaches from environmental disasters. Twenty-two hundred Florida residents were surveyed.Which of the following describes the variable of interest in the Study?

From past figures, it is predicted that 30% of the registered voters will vote in the March primary. Does this statement describe descriptive or inferential statistics?

An assembly line is operating satisfactorily if fewer than 3% of the phones produced per day are defective. To check the quality of a dayʹs production, the company randomly samples 10 phones From a dayʹs production to test for defects. Define the population of interest to the manufacturer.

A survey of high school teenagers reported that 83% of those sampled are interested in pursuing a college education. Does this statement describe descriptive or inferential statistics?

A recent report stated ʺBased on a sample of 250 truck drivers, there is evidence to indicate that, on average, independent truck drivers earn more than company-hired truck drivers.ʺ Does this Statement describe descriptive or inferential statistics?

Which of the following is not an element of descriptive statistical problems?

Statistics involves two different processes, describing sets of data and drawing conclusions about the sets of data on the basis of sampling.

A study attempted to estimate the proportion of Florida residents who were willing to spend more tax dollars on protecting the Florida coastline from environmental disasters. Thirty-nine hundred Florida residents were surveyed.Which of the following is the population used in the study?

In a survey of 2000 high school students, 14% of those surveyed read at least one best-seller each month. Give an example of a descriptive statement and an inferential statement that could be made based on this information.

An insurance company conducted a study to determine the percentage of cardiologists who had been sued for malpractice in the previous two years. The sample was randomly chosen from a National directory of doctors. What is the variable of interest in this study?

Which of the following is not the job of a statistician?