Probability

Probability

1. Basic Concpts

   • Outcomes: Possible results
   • Sample space: all possible answers
   • event: a piece of the sample space
   • expirement: observation of random phenomena

2. Formulas

   • Empirical: p(E) #of times that E happens/ #times tha E was performed
   • Theoretical: p(E) #of favorable outcomes/ total #of outcomes

3. Odds in favor : 1 to 5 Odds against: 5 to 1

4. Events Involving "NOT" and "OR"

   • Probability of the complement: P(note)= 1-P(E)
   • Impossible evente: P(0)=0
   • Certain event: P(s):1
   • Probability value:0<P(E)<1
   • Addition rule of probability: If A and B are any 2 events. P(AorB)= P(A)+P(B)- P(A and B). If A and B are mutually exclusive P (AorB)= P(A)+P(B)

5. Events involving "AND"

   • Conditional formula: P(B/A)= P(AnB)/P(A)
   • Indipendent events: P(B/A) =P(B) OR P(A/B)=P(A)
   • For any two events: P(A&B) = P (B/A). If A and B are in indipendent events P(AandB)= P(A), P(B)

6. Venn Diagrams

   • Intersection: (AnB)={xlx€ A and X€B}
   • Complement: P(A)={xlx €U and €/A}
   • Union: P(AUB)={xlx€Aor x€B}
   • Difference: P(A-B)={xlx€andx€/B}

Images and files in the map