Statistics (Applied)

Question 1

If y = ax^n , what is log(y) ?

Answer 1

Log(a) + nlog(x)

Question 2

When is a one-tailed test used?

Answer 2

When ρ is either greater or less than 0

Question 3

When is a two-tailed test used?

Answer 3

When ρ is not equal to 0

Question 4

What are the hypotheses for a one-tailed test?

Answer 4

H⁰: ρ=0 , H¹: ρ>0/ρ<0

Question 5

What are the hypotheses for a two-tailed test?

Answer 5

H⁰: ρ=0 , H¹: ρ≠0

Question 6

In Set Notation, how is the event ‘A and B’ written?

Answer 6

AnB

Question 7

If A and B are independent, what is P(AnB)?

Answer 7

P(A) x P(B)

Question 8

If A and B are mutually exclusive, what is P(AnB)

Answer 8

0 (it doesn’t exist, as they don’t intersect)

Question 9

In Set Notation, how is the event ‘A or B’ written?

Answer 9

AUB

Question 10

If A and B are mutually exclusive, what is P(AUB)?

Answer 10

P(A) + P(B)

Question 11

In Set Notation, how is the event ‘Not A’ written?

Answer 11

A’

Question 12

What is the formula for P(A’)?

Answer 12

1 - P(A)

Question 13

In Set Notation, how is the probability that B occurs given that A has already occurred written?

Answer 13

P(B/A)

Question 14

For independent events, what P(A/B) the same as?

Answer 14

P(A/B’) = P(A)

Question 15

What is the formula for P(AUB)?

Answer 15

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

Question 16

What does the Product Moment Correlation Coefficient measure?

Answer 16

The linear correlation between two variables

Question 17

What range of values can the product moment correlation coefficient take?

Answer 17

-1 to 1

Question 18

What letter denotes the product moment correlation coefficient?

Answer 18

r

Question 19

What does a product moment correlation coefficient of 1 mean?

Answer 19

There is a perfect positive linear correlation

Question 20

What does a product moment correlation coefficient of -1 mean?

Answer 20

There is perfect negative linear correlation

Question 21

What does a product moment correlation coefficient of 0 mean?

Answer 21

There is no linear correlation

Question 22

When is PMCC denoted r, and when is it denoted ρ?

Answer 22

r - a sample
ρ - whole population

Question 23

How do you determine the critical region for r for your (one-tailed/two-tailed) hypothesis?

Answer 23

By using the table of critical values in the formula book

Question 24

In a normal distribution, what is the formula for the mean?

Answer 24

μ = np

n = population/trials etc.
p = probability

Question 25

In a normal distribution, what is the formula for variance?

Answer 25

σ = npq

n = population/trials etc.
p = probability
q = 1 - p

Question 26

What is the equation for a Z-score?

Answer 26

Z = (X - μ)/σ