AP Statistics 1.2 A Identify Observational Units Variables Parameters and Statistics From a Statistical Study or Data Set Questions

Practise identifying variables and population parameters from study descriptions, translating the quantity measured and the target summary into context.

Exam points

Name each measured variable with its observational-unit context and units where relevant.
Define the population parameter as a contextual summary, such as a mean over all target units.

An environmental research agency conducted a study of a certain state's roadsides to estimate the mean number

of discarded cans and bottles per mile of public road. The state's public roads were grouped into three types:

Major highways: major paved roads designed for high traffic volume

Minor highways: smaller paved roads designed for low traffic volume

Unpaved roads: gravel and dirt roads

There are about 100,000 miles of public roads in the state. The environmental research agency defined a

sampling unit to be a one-mile segment of public road. Using a database supplied by the state's department of

transportation, the agency randomly selected 30 one-mile road segments for each of the three types of roads.

Researchers from the agency searched the roadsides along each of the selected one-mile road segments and

recorded the number of discarded cans and bottles. Results are shown in the table below.

Table for Question AP Statistics 1.2 A Identify Observational Units Variables Parameters and Statistics From a Statistical Study or Data Set Questions question 1 — AP Statistics

What is the variable of interest in the study?

What is the parameter of interest?

All question bank results loaded

AP Statistics 1.2 A Identify Observational Units Variables Parameters and Statistics From a Statistical Study or Data Set Questions question 1