What is the difference between probability and possibility of an event ?

I have been wondering about this apparently paradoxical situation of possibility and probability of any event. It's like when do we say an event is probable to occur and there is a possibility of the event to occur.What is the difference between probability and possibility of an event ?
If you say an event is probable, that usually means that the odds are greater than 1 in 2, or 50%. If an event is possible, that means that it has a probability of occurring that is greater than 0, and less than 1. It might be very high (close to 1), or it might be very low (close to 0). Some people might say that an event with a probability of 1 is also possible, but to me, "possible" implies that it's not certain.



For example, if you play the lottery, you've got very low odds of hitting the jackpot. The Florida lottery has odds of 1 in 23 million. It's not very likely that you'll win, but it is possible, because 1 / 23,000,000 is greater than 0, and less than 1.



If you flip a coin, you've got just under a 1 in 2 chance of getting heads. It's possible to get heads, because 0 %26lt; 1/2 %26lt; 1.



If you flip that coin again, you can be almost certain that you will land on either heads or tails. But the coin could, very rarely, land on its edge. If 999,999 times out of a million, the coin comes up either heads or tails, then it's possible to get heads or tails, because 0 %26lt; 999,999 / 1,000,000 %26lt; 1.



Now, what if you didn't play the lottery, or you flipped a coin and expected to get heads AND tails? There's no way to win either of those - there is no possibility. The probability is EXACTLY equal to 0.



But what if we bought a lottery ticket for every possible combination of numbers? Or what if we flipped a coin and bet that it would come down either heads, tails, or on edge? Winning at both of those is not just possible, it's CERTAIN. The probability is EXACTLY equal to 1.



These kinds of distinctions are important in the work I do - I try to calculate the odds that a rocket will crash land and kill someone. We stack up a bunch of different probabilities - what is the probability that a component will fail? What is the probability that that leads to a crash? What is the probability that there are people around the crash site? What is the probability that someone near the crash site would be killed? Basically, all of those probabilities get multiplied together, and the government sets limits on how high the result can be.



The probabilities of a crash are very close to zero, but they're not quite. And we can't just round them down to zero, because then when we do the multiplication by zero, we get an answer of zero. But that's not acceptable, because we know that it's POSSIBLE (but hopefully NOT PROBABLE) that a crashing rocket could kill someone.



I hope that helps you out!What is the difference between probability and possibility of an event ?
To say that an event is possible means only that there is a greater than zero chance of it happening. It says nothing about whether the event is LIKELY to occur. For example, it's POSSIBLE that Bruce Willis could be elected the next President of the United States (I'm not aware of anything that would disqualify him). It isn't very likely, but there's a miniscule chance that he could decide to run and be elected. "Possible" describes every event that could happen.



Probability describes how like an event is. If an event isn't possible, then it has no probability, but if an event IS possible, then it can have any probability from almost zero to 1 (where 1 indicates an absolute certainty). For example, suppose that you put 100 plastic chips into a bag. 99 of the chips are red, and 1 is white. Is it possible that you could draw the white chip out on the first try? Yes. There is a non-zero chance of that happening (0.01, or 1%). However, it isn't probable to happen. There is a much greater probability that the first chip you draw will be red.



Make sense?What is the difference between probability and possibility of an event ?
If there are 100 coins in a hat. 99 pennies. 1 dime.



What are the possible events if I take a coin out?



a penny or a dime. 2 possibilities.



What are the probabilities of a penny or a dime?



99/100 for the penny

1/100 for the dime



a probability is a value between 0 and 1. 1/100, a small probability...

a possibility is a description of an event outcome, "a penny!"
Probability is a concept, it's defined mathematically so it can be computed, on the other hand possibility can not be predicted or calculated directly. Possibility of things happening based on probability.