Exam 1: Statistics, Data, and Statistical Thinking

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.

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.

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

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

A personnel director studied the eating habits of a companyʹs employees. The director noted whether employees brought their own lunch to work, ate at the company cafeteria, or went out to Eat lunch. This type of data collection would best be considered as a(n)__________.

A study in the state of Georgia was conducted to determine the percentage of all community college students who have taken at least one online class. 1500 community college students were Contacted and asked if they had taken at least one online class during their time at their Community college. These responses were then used to estimate the percentage of all community College students who have taken at least one online class. Identify the variable of interest in this Study.

Three female students and two male students are to be chosen from a group of 30 female students and 20 male students. Does this sample of five students satisfy the conditions to be a random sample of the 50 students in the group? Explain.

A variable is a characteristic or property of a population.

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?

A health food company has the following statement on their new product packaging: ʺPrevents all types of cancer!ʺ (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.

A fan observes the numbers on the shirts of a girlʹs soccer team. Identify the type of data collected.

What is meant by selection bias?

What is meant by a representative sample?)

Which data about paintings would not be qualitative?

A study in the state of Georgia was conducted to determine the percentage of all community college students who have taken at least one online class. 1500 community college students were Contacted and asked if they had taken at least one online class during their time at their Community college. These responses were then used to estimate the percentage of all community College students who have taken at least one online class. What type of variable is being collected?

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?

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?

A student worked on her statistics project in the library and found a reference book that contained the median family incomes for all 50 states. On her project, she would report her data as being Collected __________.

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?

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.