What is a Random Variable?When the value of a variable is determined by a chance event, that variable is called a random variable. Show
Note: Your browser does not support HTML5 video. If you view this web page on a different browser (e.g., a recent version of Edge, Chrome, Firefox, or Opera), you can watch a video treatment of this lesson. Discrete vs. Continuous Random VariablesRandom variables can be discrete or continuous.
Discrete Variables: Finite vs. InfiniteSome references state that continuous variables can take on an infinite number of values, but discrete variables cannot. This is incorrect.
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 UnderstandingProblem 1 Which of the following is a discrete random variable? I. The average height of a randomly selected group of boys. (A) I only 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. 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.
Comparison Chart
Definition of Discrete VariableA 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 VariableContinuous 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 VariableThe difference between discrete and continuous variable can be drawn clearly on the following grounds:
ExamplesDiscrete Variable
Continuous Variable
ConclusionBy 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.
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