Категории: Все - counting - combinations - independent - conditional

по Sarah Schuelke 11 лет назад

529

Probability and Counting Chart

The text delves into the fundamental concepts of probability and counting, essential components in statistical and mathematical analysis. It explains various counting rules, including the Fundamental Counting Rule, Factorial Rule, Combinations Rule, and Permutations Rule, each describing different methods of arranging and selecting items.

Probability and Counting Chart

Probability and Counting

Probability

Addition Rule
Mutural Exclusive?

P(A or B) = P(A) + P(B) - P(both)

P(A or B) = P(A) + P(B)

Complement

"At least one" = one or more

-complement of getting at least one particular event means that you get NO occurance of that event.

P(A) and P(A -)

Conditonal Probability
P(B| A) = P(A & B) / P(A)
Mutiplication
Independent?

No

Dependent

Dependent: if A & B are not independent

-selection without replacement

P(A & B) = P(A) * P(B| A)

P(B|A) = probability of event B occuring after event A

Yes

Independent

Independent: if occurance of events A and B does not affect the probability of the occurance of the other.

- with replacement

-5% rule

P(A) * P(B)

Classic and Realative Frequency Probability

P(E) = # of ways E occurs/ total # of outcomes

Counting

Factorial Rule
n!

n! = # of different permutations of 'n' different items when all 'n' of them are selected.

Fundamental Counting Rule
m * n
Combinations Rule

Combinations -are arrangements in which different sequences of the same items are not counted separately.

nCr = n! / ((n-r)!r!)

nCr = n! / ((n-r)!r!) = # of different combinations (order doesn't matter) when 'n' different items are available but only 'n' of them are selected without replacement.

Permutations Rule

Permutations are arrangements in which different sequences of the same items are counted separately

n! n1! n2!....nk!

n!n1!n2! ...nk! = # of different permutations when 'n' items are available and all 'n' are selected without replacement, but some items are identical to others.