Stats Year 2

Question 1

If y = ax^n for constants a and n, then log(y) =

Answer 1

log(a) + nlog(x)

Question 2

If y = kb^x for constants k and b, then log(y) =

Answer 2

log(k) + xlog(b)

Question 3

What does r tell us?

Answer 3

= 1 then perfect positive linear correlation
= 0 no linear correlation
= -1 then perfect negative linear correlation

Question 4

1.3

Answer 4

1.3

Question 5

A and B

Answer 5

AnB

Question 6

A or B

Answer 6

AuB

Question 7

Not A

Answer 7

A’

Question 8

The probability that B occurs given that A has already occurred

Answer 8

P(B|A)

Question 9

For independent events, p(A|B) =

Answer 9

= P(A|B’) = p(A)

Question 10

Formula for P(AuB)

Answer 10

P(A) + P(B) - P(AnB)

Question 11

Formula for P(B|A)

Answer 11

P(BnA) / P(A)

Question 12

What is the area under a continuous probability distribution equal to?

Answer 12

1

Question 13

What is mew equal to for normal distribution

Answer 13

mean

Question 14

What is sigma squared equal to in normal distribution

Answer 14

the population variance

Question 15

The normal distribution is symmetrical, what does this mean?

Answer 15

mean = median = mode

Question 16

WHat does the normal distribution have at each end?

Answer 16

Asymptopes

Question 17

Where are the normal distribution poitns of inflection?

Answer 17

mew plus or minus sigma

Question 18

Mean and SD of standard normal distribution

Answer 18

mean = o, sd = 1

Question 19

The standard nomrla variable

Answer 19

z -- N(0, 1^2)

Question 20

Z =

Answer 20

(X - mew) / sigma