# Random variable and density function

And you can watch the calculus videos if you want to learn a little bit more about how to do them.

And let's say I don't know what the actual probability distribution function for this is, but I'll draw one and then we'll interpret it.

For a continuous random variable, the probability density function provides the height or value of the function at any particular value of x; it does not directly give the probability of the random variable taking on a specific value.

In the case of this example, the probability that a randomly selected hamburger weighs between 0.

## Probability density function questions

The binomial probability mass function equation 6 provides the probability that x successes will occur in n trials of a binomial experiment. And the example I gave for continuous is, let's say random variable x. Or they don't have to be 0. And I would say no, it is not a 0. You have discrete, so finite meaning you can't have an infinite number of values for a discrete random variable. They have to add to 1. Geometric visualisation of the mode , median and mean of an arbitrary probability density function. And I say rain because I'm in northern California. Normally our measurements, we don't even have tools that can tell us whether it is exactly 2 inches. So if we said that the absolute value of Y minus is 2 is less than some tolerance? For those of you who've studied calculus. The probability is much higher. And we draw like this. Let me go up here.

A probability density function must satisfy two requirements: 1 f x must be nonnegative for each value of the random variable, and 2 the integral over all values of the random variable must equal one.

Let's test this definition out on an example. In the latter case, the temperature could be It might not be obvious to you, because you've probably heard, oh, we had 2 inches of rain last night.

And then we moved on to the two types of random variables. Probabilities for the normal probability distribution can be computed using statistical tables for the standard normal probability distribution, which is a normal probability distribution with a mean of zero and a standard deviation of one.

## How to find probability density function of a continuous random variable

No ruler you can even say is exactly 2 inches long. So it's important to realize that a probability distribution function, in this case for a discrete random variable, they all have to add up to 1. In the development of the probability function for a discrete random variable, two conditions must be satisfied: 1 f x must be nonnegative for each value of the random variable, and 2 the sum of the probabilities for each value of the random variable must equal one. Or they don't have to be 0. In reality, I'm not particularly interested in using this example just so that you'll know whether or not you've been ripped off the next time you order a hamburger! Like that. Because when a random variable can take on an infinite number of values, or it can take on any value between an interval, to get an exact value, to get exactly 1.

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