Statistics MH Chapter 1 HW

The names of the positions in a corporation, such as chief operating officer or controller, are examples of what type of variable?

Qualitative - Explanation The variable, job title, is qualitative.

Explain the difference between qualitative and quantitative variables.

Qualitative data is not numerical, whereas quantitative data is numerical

What type of variable is the number of robberies reported in your city?

Quantitative - Explanation The number of robberies is counted and must be a whole number, such as 0, 500, or 3,125,874.

Explain the difference between a sample and a population.

A sample is a subset taken from a population

AVX Home Entertainment, Inc., recently began a "no-hassles" return policy. A sample of 315 customers who recently returned items showed 130 thought the policy was fair, 170 thought it took too long to complete the transaction, and the rest had no opinion. On the basis of this information, make an inference about customer reaction to the new policy. (Round your answers to 1 decimal place.)

Customer Reaction Percent Fair 41.3 % Too long 54 % No opinion 4.8 % The above data suggest that majority of the customers believe it took too long to complete the transaction. Explanation The obvious majority of consumers (170/315, or 54.0%) believe it took too long to complete the transaction with only 41.3% believe the policy is fair (130/315). On the strength of these findings, we anticipate all customers will feel the same and does not support the new policy.

What type of variable is the number of auto accidents reported in a given month?

Discrete

Explain the difference between a discrete and a continuous variable.

Discrete variables can assume only certain values, but continuous variables can assume any valueswithin some range.

Which one of the following is NOT an example of discrete data?

Distance between New York City and Chicago - Explanation Discrete variables can assume only certain values, and there are gaps between the values. Miles are not discrete because they can be measured with any number of decimal point values.

The principal difference between the interval and ratio scale is that the ratio scale has a meaningful zero point.

True - Explanation This is the principal difference between interval and ratio level data. Interval level data has no true zero, so zero is just a point on a scale rather than the absence of something. Ratio level data has a true zero point, so zero means the absence of something. For example, if you have a zero balance in your savings account, it means you have no money saved.

Statistics are used as a basis for making decisions.

True - Explanation This is the ultimate purpose of statistics. After we organize, summarize, and analyze data, we make decisions based on our summaries and analysis.

What is the level of measurement for each of the following variables

a. Student IQ ratings. Intervals b. Distance students travel to class. Ratio c. The jersey numbers of a sorority soccer team.Nominal d.A student's state of birth.Nominal e.A student's academic class—that is, freshman, sophomore, junior, or senior. Ordinal f.Number of hours students study per week.Ratio

For the following questions, would you collect information using a sample or a population?

a. To find how many books are published in one week by a famous publishing company. Population b. To test a new drug produced by a biotech company. Sample c. To find the number of men and women working in an IT company with 600 people. Population d. To estimate the average salary of doctors in California. Sample

Height and weight are examples of which level of measurement?

Ratio - Explanation Height and weight are ratio variables that have a zero point, and the ratio between two values is meaningful.

The Struthers Wells Corporation employs more than 10,000 white-collar workers in its sales offices and manufacturing facilities in the United States, Europe, and Asia. A sample of 300 U.S. workers revealed 120 would accept a transfer to a location outside the United States. On the basis of these findings, write a brief memo to Ms. Wanda Carter, Vice President of Human Services, regarding all white-collar workers in the firm and their willingness to relocate.

As a result of these sample findings, we can conclude that 40 % of the white-collar workers would transfer outside the U.S. Explanation As a result of these sample findings, we can conclude that 120/300 or 40% of the white-collar workers would transfer outside the U.S.

______ is an example of a qualitative variable.

Color of ink in a pen - Explanation Color is a qualitative variable because it is an attribute that can be observed but not measured.

What type of variable is the number of gallons of gasoline pumped by a filling station during a day?

Continuous - Explanation The number of gallons pumped is a numerical variable that can assume any value within a range. There are no gaps in the scale, so the data are continuous.

Descriptive statistics are used to find out something about a population based on a sample.

False - Explanation Inferential statistics uses sampling to estimate a property of a population.

A marketing class of 50 students evaluated the instructor using the following scale: superior, good, average, poor, or inferior. The descriptive summary showed the following survey results: 2% superior, 8% good, 45% average, 45% poor, and 0% inferior. What is the correct conclusion for this summary?

Most students rated the instructor as poor or average. - Explanation The percentages indicate that 90% of the 50 students rated the instructor as average or poor. No students rated the instructor as inferior. "Great" was not measured.

The science of collecting, organizing, presenting, analyzing, and interpreting data to assist in making more effective decisions is referred to as statistics.

True - Explanation This is another possible definition of statistics.

The length of a bridge, measured in meters, is an example of ______.

quantitative data - Explanation Measurements are quantitative data because the results are numerical and the numbers have meaning. Qualitative data is based on counting how many items fall into particular categories or classifications. An example would be counting the number of students in a class with various eye colors.