What is a distribution?

What is a distribution? In statistics, when we use the term distribution, we usually mean a probability distribution. Good examples are the Normal distribution, the Binomial distribution, and the Uniform distribution.
A distribution is a function that shows the possible values for a variable and how often they occur.
Think about a die. It has six sides, numbered from 1 to 6. We roll the die. What is the probability of getting 1?
It is one out of six, so one-sixth, right? What is the probability of getting 2? Once again - one-sixth. The same holds for 3, 4, 5 and 6.
Now. What is the probability of getting a 7? It is impossible to get a 7 when rolling a die.
Therefore, the probability is 0.
The distribution of an event consists not only of the input values that can be observed, but is made up of all possible values. So, the distribution of the event - rolling a die - will be given by the following table. The probability of getting one is 0.17, the probability of getting 2 is 0.17, and so on... you are sure that you have exhausted all possible values when the sum of probabilities is equal to 1% or 100%. For all other values, the probability of occurrence is 0.
Each probability distribution is associated with a graph describing the likelihood of occurrence of every event. Here’s the graph for our example. This type of distribution is called a uniform distribution.
It is crucial to understand that the distribution is defined by the underlying probabilities and not the graph. The graph is just a visual representation.
Alright. Now think about rolling two dice. What are the possibilities? One and one, two and one, one and two, and so on. Here’s a table with all the possible combinations. We are interested in the sum of the two dice. So, what’s the probability of getting a sum of 1? It’s 0, as this event is impossible. What’s the probability of getting a sum of 2? There is only one combination that would give us a sum of 2 – when both dice are equal to 1. So, 1 out of 36 total outcomes, or 0.03. Similarly, the probability of getting a sum of 3 is given by the number of combinations that give a sum of three divided by 36. Therefore, 2 divided by 36, or 0.06. We continue this way until we have the full probability distribution.

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[danielepolverigiani]

Great introduction to statistics.
It is sad that it has so few views with all the effort you put for it to make it short simple and graphically nice.

[kennyjohn]

Thanks btw it made me understand distribution more

[sammyrajoy]

I'm preparing for CRISC and was reading about Risk Assessment Techniques. Bayesian Analysis method got me here. Thank you for this video.

[sergeilenkov]

There is a slight disadvantage of using decimals for probabilities, as the sum of those rounded values won't always equal 1, or even worse, would be >1 like with your one dice example (1.02)

[tuyenbui]

The video sound is pretty good, beyond my imagination

[thaothu]

how did you do it can you share with me, thank you

[vinnycaporaletti]

the video image is too poor, you need to fix it more

[anaforero]

Is "rolling a die" the event or the random variable? I'm confused with the terminology.

[harishganesan]

0.17 should be read as point one seven and not seventeen

[duongnguyen-synu]

how did you do it can you share with me, thank you