Does a discrete random variable have to take on a positive value?
Your intuition is correct — a discrete variable can take on negative values. The example is just an example: a person can’t have −2 children, but the difference in scores between Home and Away sports teams can be −2 when the Home team is behind by two points.
Are random variables discrete?
Random variables can be classified as either discrete (that is, taking any of a specified list of exact values) or as continuous (taking any numerical value in an interval or collection of intervals).
Why is a random variable discrete?
A discrete random variable is one which may take on only a countable number of distinct values such as 0,1,2,3,4,…….. Discrete random variables are usually (but not necessarily) counts. If a random variable can take only a finite number of distinct values, then it must be discrete.
Can discrete random variable be negative?
All Answers (7) Yes, they can be negative Consider the following game. A fair 4-sided die, with the numbers 1; 2; 3; 4 is rolled twice. If we let X denote the (possibly negative) winnings of the player, what is the probability mass function of X? (X can take any of the values -3;-2;-1; 0; 1; 2; 3.)
Is random variable always positive?
A “negative” random variable is one that is always negative – that is: P(X<0)=1. Similarly, for “positive,” P(X>0)=1. Note that a positive random variable is necessarily non-negative. But a non-negative random variable can be zero.
Which of the following is an example of a discrete variable?
Discrete variables are countable in a finite amount of time. For example, you can count the change in your pocket. You can count the money in your bank account. You could also count the amount of money in everyone’s bank accounts.
Which random variable is discrete?
A discrete random variable X has a countable number of possible values. Example: Let X represent the sum of two dice. To graph the probability distribution of a discrete random variable, construct a probability histogram. A continuous random variable X takes all values in a given interval of numbers.
What are the types of discrete random variables?
Types of discrete random variables: Bernoulli, indicator, binomial, geometric, hypergeometric, Poisson. Distribution function and its properties.
How do you find the discrete random variable?
The mean of a discrete random variable, X, is its weighted average. Each value of X is weighted by its probability. To find the mean of X, multiply each value of X by its probability, then add all the products. The mean of a random variable X is called the expected value of X.
Can a random variable be negative?
Can a discrete random variable be a negative?
Yes, discrete random variable can be negative. Please check the article on this topic:
Which is an example of the support of a random variable?
The support of a random variable is the set of values that the random variable can take. For discrete random variables, it is the set of all the realizations that have a strictly positive probability of being observed. Example If a discrete random variable has probability mass function its support, denoted by , is
Which is an example of support of a discrete variable?
Support of a discrete variable. For discrete random variables, it is the set of all the realizations that have a strictly positive probability of being observed. Example If a discrete random variable has probability mass functionits support, denoted by , is.
When is a random variable said to be continuous?
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.