Question

Flight Arrivals. Listed below are the arrival delay times (min) of randomly selected American Airlines flights that departed from JFK in New York bound for LAX in Los Angeles. Negative values correspond to flights that arrived early and ahead of the scheduled arrival time. Use these values for Exercises 1–4.

-30 -23 14 -21 -32 11 -23 28 103 -19 -5 -46

Level of Measurement What is the level of measurement of these data (nominal, ordinal, interval, ratio)? Are the original unrounded arrival times continuous data or discrete data?

Short answer

The level of measurement of the data values is the ratio level.

The arrival delay times are continuous data.

Step-by-step solution

Given information

A sample of arrival delay times (in minutes) is given for a set of American Airlines flights from New York to LA.

Levels of measurement

The following levels of measurement are commonly defined:

Nominal: If the values of the variables contain names/tags that cannot be arranged in an order, they are measured on a nominal scale.

Ordinal: If the values of the variables contain names/tags that can be ordered, but the distance between each ordered value is neither known nor fixed, they are measured on an ordinal scale.

Interval:If the values are numerical, and the difference between any two values can be measured, they are measured on an interval scale. The values do not contain an absolute zero value.

Ratio: If the variable contains numerical values whose ratios can be computed, they are measured on a ratio scale. The absolute zero value of this variable is meaningful.

Here, the arrival delay times (in minutes) are numerical, their ratios can be computed (a 20-minute delay time is half of a 40-minute delay time), and the absolute zero value is meaningful (a 0-minute delay time represents no delay time).

Thus, the arrival delay times are measured on a ratio scale.

Discrete data vs. continuous data

Distinct numeric values that can only be counted and do not contain decimals are discrete data.

Numeric values that can be measured over a range and can contain decimals are continuous data.

As the arrival delay times are measured over an interval and can contain decimal values, they are continuous data.