Mutually exclusive/independent events

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Mutually exclusive events cannot occur simultaneously, meaning if one event happens, the other cannot. In contrast, independent events do not influence each other's outcomes; the occurrence of one does not affect the probability of the other. For example, flipping a coin results in heads or tails as mutually exclusive events, while multiple flips are independent of each other. Additionally, drawing cards from a deck illustrates these concepts, where drawing an ace and a king are mutually exclusive, while drawing an ace and a spade are not. Understanding these distinctions is crucial for grasping basic probability concepts.
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Can someone please explain to me what the difference is between these two terms (in words, not maths)?

If A and B are mutually exclusive events, then A and B can't both happen at the same time. Is that right? What's the difference between that and if A and B were independent? :confused:
 
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Coin flip example:

One flip: Heads or Tails are mutually exclusive events

Two flips: The outcome of each flip is independent.
 
That sort of makes sense, thanks.
 
Nylex said:
If A and B are mutually exclusive events, then A and B can't both happen at the same time. Is that right?
Right.
What's the difference between that and if A and B were independent? :confused:
For starters, there is a link between mutually exclusive events- they can't both happen at once. However, there is no link between independent events- they don't effect each other at all. It might be easier to understand if you also consider non-mutually-exclusive events and dependent events.
If I draw one card from a deck, drawing an ace and drawing a king are mutually exclusive events- a single card cannot be both an ace and a king. However, drawing an ace and drawing a spade are not mutually exclusive events- a single card can be both an ace and a spade.
If I draw one card, return that card to the deck, and then draw another card, the draws are independent of each other- the sample space is the same for both draws because I returned the first card to the deck. If I draw one card, but do not return that card to the deck, and then draw another card, these events are dependent- the sample space is different since I didn't return the first card to the deck. Say I drew an ace the first time. Then there is one less card and one less ace in the deck, so the probabilities for the second draw have changed.
So mutually exclusive events are contrasted with non-mutually-exclusive events, asking whether one event excludes the other. Independent events are contrasted with dependent events, asking whether one event effects the probability of the other.
 
Thanks, honestrosewater, that's also good :smile:.
 
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