Question 1

Does online teaching help or hinder student learning? To help answer this question, a statistics teacher decided to teach his three sections of a particular class using three different teaching models - a traditional face-to-face section, a completely online section, and a hybrid or blended section that incorporated both a face-to-face and online component in the section. Students were randomly assigned to the different sections, taught identical information using the different teaching formats, and given identical examinations to measure student learning. The goal was to identify if the teaching method used affected student learning performance. Identify the data collection method used in this study.

Accepted Answer

The data was collected from a designed experiment because the students were randomly assigned to the different sections, taught identical information using the different teaching formats, and given identical examinations to measure student learning.

Question 2

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 it is the smallest unit of analysis for which data is collected.

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. What type of variable is the administration interested in collecting?

Accepted Answer

The administration is interested in collecting quantitative data because they are measuring the time it takes for students to find a parking spot, which is a numerical value.

Question 4

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 140 students and recorded how long it took each of them to find a parking spot. Identify the population, sample, and variable of interest to the administrators.

Accepted Answer

The answer of Parking at a university has become a...

Question 5

Gender is one variable of interest in a study of the effectiveness of a new medication. For data entry purposes, the researcher conducting the study assigns 1 for Male and 2 for female. Is the gender data quantitative or qualitative?

Accepted Answer

The answer of Gender is one variable of interest in...

Question 6

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. What type of variable is being collected?

Accepted Answer

The current prices of stocks are numerical values that can be measured and ordered, making them quantitative data.

Question 7

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 variable of interest to the university administration.

Accepted Answer

The variable of interest to the university administration is the parking time, defined as the amount of time the student spent finding a parking spot.

Question 8

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. Identify the sample of interest for this study.

Accepted Answer

The sample of interest is the 500 NYSE stocks that were randomly selected and whose current prices were collected for the study.

Question 9

What is the most common way to satisfy the representative sample requirement?

Accepted Answer

The answer of What is the most common way to...

Question 10

A researcher studying malnutrition among children in a developing country collected weights of a random sample of children using a scale that she had set to give weights 2.5 kilograms less than the actual weight. Which statement best describes this situation?

Accepted Answer

The scale consistently underreports the actual weight by 2.5 kilograms, which is a systematic measurement error. If the researcher knowingly uses this incorrect scale, it is unethical as it misrepresents the true data.

Question 11

A health food company has the following statement on their new product packaging: "Prevents all types of cancer!" (Fact: Past studies have shown that some ingredients in the new product have been know to possibly reduce the risk of many types of cancer). Discuss why it is unethical to make this statement.

Accepted Answer

The answer of A health food company has the following...

Question 12

In a survey of 3000 high school students, 15% 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 3000 high school...

Question 13

What is meant by selection bias?

Accepted Answer

The answer of What is meant by selection bias?...

Question 14

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 parking time data was collected.

Question 15

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. Identify the experimental unit of interest for this study.

Accepted Answer

The experimental unit of interest is a single stock traded on the NYSE, as each stock's current price is being measured and analyzed.

Question 16

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 the role of a decision-maker or manager, not a statistician. A statistician's role is more focused on data analysis and interpretation.

Question 17

What is meant by a representative sample?

Accepted Answer

The answer of What is meant by a representative sample?...

Question 18

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, as the administrators want to determine the average parking time for all students, not just the sample of 250.

Question 19

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 presenting data about the current prices of the selected stocks without making predictions or inferences about a larger population.

Question 20

A quality inspector tested 76 copiers in an attempt to estimate the average failure rate of the copier model. His study indicated that the number of failures decreased from two years ago, indicating an increase in the reliability of the copiers. Describe the variable of interest to the inspector.

Accepted Answer

The answer of A quality inspector tested 76 copiers in...

Quiz 1: Statistics, Data, and Statistical Thinking