What random variable can assume an infinite number of values in one or more intervals?

What is a Random Variable?

When the value of a variable is determined by a chance event, that variable is called a random variable.

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Discrete vs. Continuous Random Variables

Random variables can be discrete or continuous.

  • Continuous. Continuous variables, in contrast, can take on any value within a range of values. For example, suppose we randomly select an individual from a population. Then, we measure the age of that person. In theory, his/her age can take on any value between zero and plus infinity, so age is a continuous variable. In this example, the age of the person selected is determined by a chance event; so, in this example, age is a continuous random variable.

Discrete Variables: Finite vs. Infinite

Some references state that continuous variables can take on an infinite number of values, but discrete variables cannot. This is incorrect.

  • In other cases, however, discrete variables can take on an infinite number of values. For example, the number of coin flips that result in heads could be infinitely large.

When comparing discrete and continuous variables, it is more correct to say that continuous variables can always take on an infinite number of values; whereas some discrete variables can take on an infinite number of values, but others cannot.

Test Your Understanding

Problem 1

Which of the following is a discrete random variable?

I. The average height of a randomly selected group of boys.
II. The annual number of sweepstakes winners from New York City.
III. The number of presidential elections in the 20th century.

(A) I only
(B) II only
(C) III only
(D) I and II
(E) II and III

Solution

The correct answer is B.

The annual number of sweepstakes winners results from a random process, but it can only be a whole number - not a fraction; so it is a discrete random variable. The average height of a randomly-selected group of boys could take on any value between the height of the smallest and tallest boys, so it is not a discrete variable. And the number of presidential elections in the 20th century does not result from a random process; so it is not a random variable.

What random variable can assume an infinite number of values in one or more intervals?
Variable refers to the quantity that changes its value, which can be measured. It is of two types, i.e. discrete or continuous variable. The former refers to the one that has a certain number of values, while the latter implies the one that can take any value between a given range.

Data can be understood as the quantitative information about a specific characteristic. The characteristic can be qualitative or quantitative, but for the purpose of statistical analysis, the qualitative characteristic is transformed into quantitative one, by providing numerical data of that characteristic. So, the quantitative characteristic is known as a variable. Here in this article, we are going to talk about the discrete and continuous variable.

  1. Comparison Chart
  2. Definition
  3. Key Differences
  4. Examples
  5. Conclusion

Comparison Chart

Basis for ComparisonDiscrete VariableContinuous Variable
Meaning Discrete variable refers to the variable that assumes a finite number of isolated values. Continuous variable alludes to the a variable which assumes infinite number of different values.
Range of specified number Complete Incomplete
Values Values are obtained by counting. Values are obtained by measuring.
Classification Non-overlapping Overlapping
Assumes Distinct or separate values. Any value between the two values.
Represented by Isolated points Connected points

Definition of Discrete Variable

A discrete variable is a type of statistical variable that can assume only fixed number of distinct values and lacks an inherent order.

Also known as a categorical variable, because it has separate, invisible categories. However no values can exist in-between two categories, i.e. it does not attain all the values within the limits of the variable. So, the number of permitted values that it can suppose is either finite or countably infinite. Hence if you are able to count the set of items, then the variable is said to be discrete.

Definition of Continuous Variable

Continuous variable, as the name suggest is a random variable that assumes all the possible values in a continuum. Simply put, it can take any value within the given range. So, if a variable can take an infinite and uncountable set of values, then the variable is referred as a continuous variable.

A continuous variable is one that is defined over an interval of values, meaning that it can suppose any values in between the minimum and maximum value. It can be understood as the function for the interval and for each function, the range for the variable may vary.

Key Differences Between Discrete and Continuous Variable

The difference between discrete and continuous variable can be drawn clearly on the following grounds:

  1. The statistical variable that assumes a finite set of data and a countable number of values, then it is called as a discrete variable. As against this, the quantitative variable which takes on an infinite set of data and a uncountable number of values is known as a continuous variable.
  2. For non-overlapping or otherwise known as mutually inclusive classification, wherein the both the class limit are included, is applicable for the discrete variable. On the contrary, for overlapping or say mutually exclusive classification, wherein the upper class-limit is excluded, is applicable for a continuous variable.
  3. In discrete variable, the range of specified number is complete, which is not in the case of a continuous variable.
  4. Discrete variables are the variables, wherein the values can be obtained by counting. On the other hand, Continuous variables are the random variables that measure something.
  5. Discrete variable assumes independent values whereas continuous variable assumes any value in a given range or continuum.
  6. A discrete variable can be graphically represented by isolated points. Unlike, a continuous variable which can be indicated on the graph with the help of connected points.

Examples

Discrete Variable

  • Number of printing mistakes in a book.
  • Number of road accidents in New Delhi.
  • Number of siblings of an individual.

Continuous Variable

  • Height of a person
  • Age of a person
  • Profit earned by the company.

Conclusion

By and large, both discrete and continuous variable can be qualitative and quantitative. However, these two statistical terms are diametrically opposite to one another in the sense that the discrete variable is the variable with the well-defined number of permitted values whereas a continuous variable is a variable that can contain all the possible values between two numbers.

What is a random variable that can assume only finite values?

A random variable that can assume only a finite number of values is referred to as a (n) 3. The weight of an object, measured in grams, is an example of c. either a continuous or a discrete random variable, depending on the weight of the object d. either a continuous or a discrete random variable depending on the units of measurement

What is a (n) 4 random variable?

A random variable that can assume only a finite number of values is referred to as a (n) 4. A probability distribution showing the probability of x successes in n trials, where the probability of success does not change from trial to trial, is termed a 5. Variance is 6. A continuous random variable may assume 7.

What is a continuous random variable?

If the random variable X can assume an infinite and uncountable set of values, it is said to be a continuous random variable. When X takes any value in a given interval (a, b), it is said to be a continuous random variable in that interval. Formally, a continuous random variable is such whose cumulative distribution function is constant throughout.

What is a random variable with the probability function?

X is a random variable with the probability function: 45. A random variable that may take on any value in an interval or collection of intervals is known as a The following represents the probability distribution for the daily demand of computers at a local store. 46. Refer to Exhibit 5-1.

What random variable assume infinite number of values in one or more intervals?

Continuous variables A variable is said to be continuous if it can assume an infinite number of real values within a given interval. For instance, consider the height of a student. The height can't take any values.

Which random variable can assume an infinite number of values?

A continuous random variable is one which takes an infinite number of possible values.

Is a variable which can assume any on an infinite number if values and can be associated with points on a continuous line interval?

A continuous random variable may assume any value in an interval on the real number line or in a collection of intervals.

Is continuous random variable infinite?

A continuous random variable takes on an uncountably infinite number of possible values.