Inspection of highway bridges. All highway bridges in the United States are inspected periodically for structural deficiency by the Federal Highway Administration (FHWA). Data from the FHWA inspections are compiled into the National Bridge Inventory (NBI). Several of the nearly 100 variables maintained by the NBI are listed below. Classify each variable as quantitative or qualitative.

a. Length of maximum span (feet)

b. Number of vehicle lanes

c. Toll bridge (yes or no)

d. Average daily traffic

e. Condition of deck (good, fair, or poor)

f. Bypass or detour length (miles)

g. Route type (interstate, U.S., state, county, or city)

Short Answer

Expert verified

a. Quantitative

b. Quantitative

c. Qualitative

d. Quantitative

e. Qualitative

f. Quantitative

g. Qualitative

Step by step solution

01

Specifying the variable length of the maximum span as quantitative or qualitative

The quantitative data comprises the numerical values and talks about the quantity that is countable. The length of the maximum span is measured in feet. For example, 10 feet, 12 feet, and others are in quantity; thisvariable is quantitative.

02

Classifying the variable number of vehicles lanes as quantitative or qualitative

The number of vehicle lanes is numeric; for example, there can be 5, 7, 8, or 10 vehicle lanes. These can be measured. Hence, it is aquantitative variable.

03

Categorizing the variable toll bridge as quantitative or qualitative

The toll bridge is qualitative because it is measured as yes or no. The types or any variable that specifies categories are a part ofthe qualitative variable.

04

Indicating if the variable average daily traffic is quantitative or qualitative

Average daily traffic is measured as 24-hour traffic volume at a particular location. This variable is measured in numbers. Hence, thevariable is quantitative.

05

Denoting the condition of the deck as quantitative or qualitative

The condition of the deck can be classified as good, poor, or fair; this signals that the variable tries to indicate the class. Hence, it is aqualitative variable.

06

Classifying the variable; bypass or detour length as quantitative or qualitative

The length of any variable is a quantifiable digit hence the bypass of detour length is represented in numerals. Therefore, it isa quantitative variable.

07

Specifying the variable route types as quantitative or qualitative

The variable route types can be categorized as interstate, U.S., state, nation, or town. Hence, this is aqualitative variable.

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