Chapter 1 - Statistics and Data

A variable that is described with labels or names rather than numerically is called a(n) __________ variable.

qualitative

Samples are primarily used to

make inferences about population parameters.

Consider the following: a runner's time in a 100-meter race. This variable is best categorized as a ____________ variable.

Continuous. Time is continuous.

The branch of statistics that drams conclusions about a large set of data based on a smaller set of data is often referred to as _________ statistics.

Inferential

A characteristic of interest that differs among various observations is referred to as a _________.

Variable

The interval scale of measurement....

allows for the use of negative values.

A significant weakness of the ordinal scale is:

an inability to measure differences between the ranked values.

With nominal data, you can:

categorize the data.

The branch of statistics that summarizes important aspects of a data set is often referred to as _________ statistics.

descriptive

Data that are collected by recording a characteristic of a subject over several time periods are referred to as _______ data.

time series

A _________ includes all items of interest in a statistical problem.

Population

Which measurement scales are associated with quantitative data?

Internal and Ratio

All of the following are examples of cross-sectional data EXCEPT: A) Quarterly sales for a computer company for the last 5 years. B) The hours worked last week by 50 employees at a factory. C) Last year's starting salary for 100 recent business graduates at Penn State University. D) Last month's unemployment rate for various cities in Ohio.

A) Quarterly sales for a computer company for the last 5 years. ***This is time series data, not cross-sectional data***

Which of the following characteristics of interest is a variable? A) The number of degrees in a circle B) The number of pizzas ordered from Pizza Hut per day C) The number of letters in the alphabet D) The number of months in a year

B) The number of pizzas ordered from Pizza Hut per day ***This number varies from day to day!***

Which of the following scenarios is an example of the interval scale? A) An undergraduate's major B) The outside temperature (in degrees Fahrenheit) C) The price of a stock (in dollars) D) A runner's time in a race (in seconds)

B) The outside temperature (in degrees Fahrenheit)

Which of the following is an example of descriptive statistics? A) Conclude which of two brands of coffee is preferred by all coffee consumers based on taste-test preferences of 200 coffee drinkers. B) Estimate the percent of all U.S. voters who approve of the President's performance. C) Test whether the average lifetime of all Brand A batteries exceeds 500 hours based on lifetime data from a sample of 20 Brand A batteries. D) Calculate the percent of 2500 U.S. voters in an opinion poll who approve of the President's performance.

D) Calculate the percent of 2500 U.S. voters in an opinion poll who approve of the President's performance.

Consider the following variable: the color of a car in a parking lot. This variable is best categorized as a _____________ variable.

Qualitative described by a color rather than a number.

Sampling, rather than surveying an entire population, can offer substantial benefits. Some of those benefits include:

Saving money and time