Question 1

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

Accepted Answer

Descriptive statistics involves summarizing and visualizing data, not making predictions about a larger set of data, which is an aspect of inferential statistics.

Question 2

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. Forty-six 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 researchers are interested in, which in this case is all Florida residents.

Question 3

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 270 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 to find a parking spot" as the administrators want to determine the average time it takes for students to find parking.

Question 4

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 experimental unit of interest to the university administration.

Accepted Answer

The experimental unit is the single student that parks at the university, as the study focuses on individual students' parking times.

Question 5

An insurance company conducted a study to determine the percentage of cardiologists who had been sued for malpractice in the previous four 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 is whether the cardiologists have been sued for malpractice in the last four years, as this is what the study aims to measure.

Question 6

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 characteristics of a specific dataset, such as the average age of students in a statistics class. Inferential statistics involve making predictions or drawing conclusions about a population based on a sample of data.

Question 7

A survey of high school teenagers reported that 92% of those sampled are interested in pursuing a college education. Does this statement describe descriptive or inferential statistics?

Accepted Answer

Descriptive statistics describe the characteristics of a population, while inferential statistics make inferences about a population based on a sample. The given statement describes the characteristics of a population (high school teenagers), so it is descriptive statistics.

Question 8

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

Accepted Answer

Implementing new procedures based on study results is typically the role of a decision-maker or manager, not a statistician. Statisticians focus on data analysis, determining relevance, and assessing the reliability of conclusions.

Question 9

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

The university is using the sample data to make generalizations or inferences about the entire student parking population, which is the essence of inferential statistics.

Question 10

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 it involves summarizing and describing the current prices of the selected stocks using graphical and numerical techniques without making predictions or inferences about a larger population.

Question 11

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 is the 250 students from whom the data was collected, as they represent the subset of the population being studied to infer the average parking time.

Question 12

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 is the entire set of students that park at the university because the university administration is interested in determining the average parking time of all students, not just the 250 students that data was collected from.

Question 13

In a survey of 5000 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 5000 high school...

Question 14

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

Accepted Answer

When we use inferential statistics, we are using the data from a sample to make inferences or predictions about the larger population.

Question 15

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

Accepted Answer

This is a correct statement about the two main processes involved in statistics. Descriptive statistics involves summarizing and displaying data, while inferential statistics involves making predictions or drawing conclusions about a population based on a sample of that population.

Question 16

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 240 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 is the entire set of students who park at the university, as the administrators want to determine the average time it takes for any student to find a parking spot.

Question 17

From past figures, it is predicted that 21% of the registered voters will vote in the March primary. Does this statement describe descriptive or inferential statistics?

Accepted Answer

The statement makes a prediction about future voting behavior based on past data, which is characteristic of inferential statistics.

Question 18

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. Forty-eight hundred Florida residents were surveyed.Which of the following describes the variable of interest in the study?

Accepted Answer

The variable of interest is the response to whether residents are willing to spend more tax dollars on beach protection, as it directly relates to the study's objective.

Question 19

An assembly line is operating satisfactorily if fewer than 2% of the phones produced per day are defective. To check the quality of a day's production, the company randomly samples 50 phones from a day's production to test for defects. Define the population of interest to the manufacturer.

Accepted Answer

The population of interest is all the phones produced during the day in question, as the manufacturer wants to ensure that fewer than 2% of all phones produced are defective.

Question 20

A recent report stated "Based on a sample of 180 truck drivers, there is evidence to indicate that, on average, independent truck drivers earn more than company-hired truck drivers." Does this statement describe descriptive or inferential statistics?

Accepted Answer

This statement describes inferential statistics because it makes a generalization or inference about a population (all truck drivers) based on a sample (the 180 truck drivers).

Quiz 1: Statistics, Data, and Statistical Thinking