Help Understanding Notation for Probability

In summary: P(B)-P(A∩B))In summary, the conversation covers the notation for probability, including using "u" and "n" to represent Union and Intersection, respectively. P(A) and P(B) represent the probability of events A and B occurring by themselves, while P(AuB) represents either A or B occurring. P(AnB) is when both A and B occur at the same time. P(A') and P(B') represent the probability of not A and not B occurring, respectively. The confusing part is understanding the notation for P(A'nB), which represents when A does not occur but B does. P(A'∪B) represents either B or not
  • #1
repugno
78
0
Hello everyone, I feel ashamed to be asking someone to explain such simple notation to me, but I’m having serious problems understanding it. Any help would be deeply appreciated. Thank you.

I’ll use “u” and “n” to denote Union and Intercept as I don’t know how to make the symbols.

What I can understand of the notation is as follow.

If A and B are two events and P(A) = 0.6, P(B) = 0.3 and P(AuB) = 0.8

P(A) would be the probability of event A occurring by itself and
P(B) would be the probability of B occurring by itself.
P(AuB) would be either A or B occurring.
P(AnB) would be when A and B occurs at the same time.
P(A’) when A does not occur, so 1 – P(A)
P(B’) when B does not occur, so 1 – P(B)

Now the confusing part…

P(A’nB) What I can understand from the “n” notation is that it represents events happening at the same time, so this would be when A does not occur at all but B does.

What would P(A’uB), P(AuB’) be ?? I’m very confused now. :frown:
 
Physics news on Phys.org
  • #2
P(A'∩B) is when A doesn't occur and B does occur.

P(A∩B') is when A does occur and B doesn't occur.

P(A'∩B) = P(AUB) - P(A)

edited to add: I don't seem to have the union in my chracter set. Also, the union and intersection symbols are "& cup ;" and "& cap ;" respectively (both without the spaces), you won't be able to display them unless they are on your html chracter set though.
 
Last edited:
  • #3
Thanks for the reply.

What would this notation represent?

P(A'∪B)
P(A∪B')
 
  • #4
P(A'UB) represents either B or not A = 1 - (P(A)-P(A∩B))

p(AUB') represents either A or not B
 

1. What is probability notation used for?

Probability notation is used to represent the likelihood of an event occurring. It is a way to express the chances of something happening in a mathematical format.

2. What are the common symbols used in probability notation?

Some common symbols used in probability notation include P for probability, E for expected value, and Ω for the sample space. Other symbols may vary depending on the specific notation used.

3. How do I read and interpret probability notation?

The notation for probability is typically written as P(event), where P represents the probability and event is the specific event being considered. For example, P(heads) would represent the probability of getting a heads when flipping a coin. The notation can also be written as a fraction, such as P(event) = number of outcomes in event / total number of possible outcomes.

4. What is the difference between conditional and unconditional probability notation?

Conditional probability notation is used when the probability of an event is dependent on another event occurring. It is written as P(event A | event B), where "|" represents "given." Unconditional probability notation, on the other hand, is used when the probability is not dependent on any other event and is written as P(event).

5. How is probability notation used in real-world applications?

Probability notation is used in various fields such as statistics, finance, and science to make predictions and analyze data. It can be used to calculate the likelihood of a certain outcome, determine the expected value of an event, and make informed decisions based on probabilities.

Similar threads

  • Set Theory, Logic, Probability, Statistics
Replies
16
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
6
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
2
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
6
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
5
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
18
Views
2K
  • Set Theory, Logic, Probability, Statistics
Replies
1
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
4
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
3
Views
1K
  • Precalculus Mathematics Homework Help
Replies
5
Views
830
Back
Top