Is a random number X considered a real number?

Question

Distribution of X for a coin toss- 2 possible outcomes. I know that X is a random variable...but is it also a real number? Math/stat experts PLEAASE HELPP!!!!

ALSO- PLEASE tell me... is E(x) a random and/or real number??

Answer 1

Yes. Probability functions are real numbers. Even the rational probabilities such as 1/2 (the coin toss) are contained within the real numbers.


Doug

Answer 2

X is a random variable.

What is a random variable?

It is a function, whose domain is the sample space.

It is a real valued function, means its range are real numbers.

For the single coin toss experiment the sample space is {H,T}

You could count H as a success and when you toss the coin their are two possible real number values (number of heads in a single toss of a coin), X=0, or X=1

The probability of a H depends on the coin, if it is fair it would be 0.5, in any case there is a probability measure for each possible outcome that is listed in the sample space.

Answer 3

No. Random variables aren't the same type of objects as regular variables. A plain variable is a placeholder for an unknown quantity (a real number). A random variable is actually a function.

In algebra, when you write f(x), the letter "f" is just the name of the function, not a number. f(x) can equal a number after calculation, but f by itself doesn't mean much.

In the same way, a random variable X is a function that assigns values to events. It may be a real-valued function, but X itself is the function, not the numbers. The answer of "1/2" is the result of P(X), not X itself.

In your example, X is not well-defined. X has to relate to a quantity of something.

Now E(X) is a real number. X takes on values (they don't absolutely have to be real numbers, but they genearlly are); those values are multiplied to their probabilities, which are also real numbers. The results are simple calculations of real numbers. E(X) is a real number.

Answer 4

yes it is a real #
anything that u ca count is a real #
and if u talk about that, it is probability. and it
the probability of the question u ask is that u can find 2 possible answer.(2 possible outcomes) it can b yes, or no. so the probability is 1/2 becuz the answer is yes it is a real # and it is only on of the 2 possible answer that is right.

Answer 5

all effective genuine numbers because it truly is type of a logarithmic equation that's solid for all effective genuine numbers. also if x = a million/2, g(x) is the sq. root of three which isn't a rational decision.