Stats 2 Flashcards
f y = ax^n for constants a and n, then log(y) =
log(a) + nlog(x)
If y = kb^x for constants k and b, then log(y) =
log(k) + xlog(b)
What does r tell us?
= 1 then perfect positive linear correlation = 0 no linear correlation = -1 then perfect negative linear correlation
1.3
1.3
A and B
A n B - Intersection
A or B
A u B - Union
Not A
A’
The probability that B occurs given that A has already occurred
P(B|A)
For independent events, P(A|B) =
= P(A|B’) = p(A)
Formula for P(AuB)
P(A) + P(B) - P(AnB)
Formula for P(B|A)
P(BnA) / P(A)
What is the area under a continuous probability distribution equal to?
1
What is mew equal to for normal distribution
Mean
What is sigma squared equal to in normal distribution
The population variance
The normal distribution is symmetrical, what does this mean?
Mean = Median = Mode
What does the normal distribution have at each end?
Asymptotes
Where are the normal distribution points of inflection?
mew plus or minus sigma
Mean and SD of standard normal distribution
Mean = 0, SD = 1
The standard normal variable
z – N(0, 1^2)
Z =
(X - mew) / sigma
