Practice Questions 4.1 (Start of Exam 2)

To make an important decision in life, we want to know what type of information from statistics?

A) Population information
B) Probability information
C) Sample information
D) Probabilistic information

Why does the population contain more information than a sample?

A) The population is the totality of the individuals of interest
B) The population is used to get a sample
C) Populations are defined by the researcher, so they have more information
D) The population has more data values than a sample

Why does more data values contain more information?

A) The same reason as more words in a paragraph gives more information
B) Because calculations are more efficient with more numbers
C) Because calculation error is less for bigger numbers
D) Using more data values in the statistics gives a better idea of all the data values in the population

Select all steps used in the process to do statistical inference.

A) Theorize
B) Analyze
C) Infer

What type of statistics is used to get sample information?

A)  Descriptive statistics because they describe the sample.
B) Inferential statistics because they infer the population values.
C) Inferential statistics because they are more important than descriptive statistics.
D) Descriptive statistics because they involve mathematical calculations.

What type of statistics is used to get population information?

A) Descriptive statistics because they involve mathematical calculations.
B) Descriptive statistics because they describe the sample.
C) Inferential statistics because they infer the population values. 
D) Inferential statistics because they are more important than descriptive statistics.

Why is knowing the value of the population mean important?

A) Because it gives one value that is in the middle of all the data values.
B) Because most research papers and reports require the population mean.
C) Because it gives one value that is one of all the data values.
D) Because it is used so often in statistics and interpretation of statistics.

Please select one answer in response to the statement: "We can never know the true value of a population mean".

A) False, because the sample average is the same value as the population mean.
B) False, because population data is just another column of data that can be used in calculations.
C)  True, because we can never see the entire population to do the calculation.
D) True, because population values must be given to us.

If knowing any one value in a column of data values, why is knowing the value of the population mean important?

A) Because the population mean is the first mathematical moment when dealing with a column of data values.
B)  Because in the normal distribution, most of the data values are clustered close to the mean value.
C) Because the population mean was developed first so it is used most often.
D) Because the population mean is just one value so it is easy to interpret.

Why is the sample average important in statistics?

A) Because the sample average uses the same calculation as the population mean.
B) Because the sample average is the middle of the sample data values.
C)  Because it is the best sample estimator for the population mean.
D) Because it is one number like the population mean, so it is easy to use.

Please select all steps in the General Method for Solving Problems in Statistics.

A) Abstract
B) Theorize
C) Analyze
D) Infer

Please select what is NOT the purpose of the Process of Abstraction?

A) To convert real world information into statistical information.
B)  To see how the situation fits into the field of statistics.
C) To find out the correct equation to use to get the answer.
D) To choose the appropriate statistical method for the situation.

Please abstract the situation below by matching the symbols with their appropriate numbers.

A 30-year-old veterinarian wanted to know if the puppies born in her clinic weighed less than 0.5 pounds on average. So, she weighed 25 puppies and found a sample average weight of 0.55 pounds.

A. x̄
B. n
C. μ

__ 0.5
__ 25
__ 0.55

Please abstract the situation below by matching the symbols with their appropriate numbers.

An engineer was responsible for 5 machines making ball bearings that were supposed to be 1.2 cm in diameter with standard deviation of 0.01 cm. He suspected that one of the machines was making too small ball bearings, so he measured 37 ball bearings from this machine and found an average diameter of 1.15 cm with a standard deviation of 0.015 cm.

A. σ
B. μ
C. s
D. x̄

__ 1.15
__ 0.01
__ 1.15
__ 1.2

Please abstract the situation below by matching the symbols with their appropriate numbers.

Zillow lists the average home price in our area as $215,816 with a standard deviation of $21,500. To find out if this was still true, a real estate professional collected the data for 58 recently sold homes and found an average of $235,000 with a standard deviation of $23,500.

A. x̄
B. σ
C. s
D. μ

__ 215,816
__ 23,500
__ 21,500
__ 235,000

What are the major tools used in the Theorize step?

A. A schematic curve.
B. A probability table.
C. A transformation equation.

What occurs in the Analyze step?

A. The calculations for the method chosen.
B. Finding the appropriate t-value for the situation.
C. Converting real world information into statistical information.
D. Inferring a population value from a sample value.

What occurs in the Infer step?

A. Finding the appropriate t-value for the situation.
B. The calculations for the method chosen.
C. Converting real world information into statistical information.
D. Inferring a population value from a sample value.

Please select an appropriate end result for the following two steps of the General Method for Solving Problems in Statistics.

A. The Theorize Step
B. The Analyze Step

__ A t-value coming from probability
__ A t-value coming from the sample.

Please select the two most important inferential statistical methods.

A. Confidence intervals.
B. Hypothesis tests.