Question

Discrete/ Continuous Data Which of the following describe discrete data?

a. The numbers of people surveyed in each of the next several years for the National Health and Nutrition Examination Surveys.

b. The exact foot lengths (measured in cm) of a random sample of statistics students.

c. The exact times that randomly selected drivers spend texting while driving during the past 7 days.

Short answer

1. The number of people surveyed is a type of discrete data.

2. Foot lengths of a sample of students measured in cm are continuous data.

3. In a random sample, the number of times drivers text while driving is a form of discrete data.

Step-by-step solution

Types of data based on countability

Numerical/quantitative data is classified into two types based on whether the random variable holds values that can be counted or not.

• Discrete data:

A collection of values that are countableand fixed for a particular random variable is called discrete data. The values need not always be whole numbers.

For example, the shoe size of a man can take values in gaps of 0.5 like 7, 7.5, 8, etc., but it can never take a value of 7.82. Thus, it cannot change over time.

• Continuous data:

A collection of values that arenot countable, fall in an interval, and can change over time is called continuous data. The values are usually in decimals and have a unit.

For example, the length of cloth, the speed of a train, the time taken in a race, etc.

Classification of data

1. As the number of people surveyed can be counted, it is a discrete form of data.

2. As foot lengths of a sample of students can be measured and have units, they are considered as continuous data.

3. As the number of times that randomly selected drivers text while driving can only be counted and not measured, so it is continuous data.