S1

Question 1

How do you use R to measure correlation

Answer 1

r=1 Perfect positive
r=0 No correlation
r=-1 Perfect Negative

Question 2

Is correlation affected by coding

Answer 2

No

Question 3

How to work out Sxy

Answer 3

Σxy-(ΣxΣy)/n

Question 4

How to work out Syy

Answer 4

Σy²- (Σy)²/n

Question 5

Work out Sxx

Answer 5

Σx²- (Σx)²/n

Question 6

How do you work out the product moment correlation coeffecient

Answer 6

Sxy/√SxxSyy

Question 7

How can you tell if A and B are independant

Answer 7

P(AgivenB)=P(A)

Question 8

How can you tell if A and B are mutually exclusive

Answer 8

P(AnB)=0

Question 9

What is P(AgivenB)

Answer 9

P(AnB)/P(B)

Question 10

What is P(AuB)

Answer 10

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

Question 11

What is Standard Deviation

Answer 11

√Varience

√(Σx²/n - (Σx/n)²)

Question 12

What is the normal distribution equation

Answer 12

Z=(x-μ)/σ

Question 13

What is Variance

Answer 13

(Σx²/n - (Σx/n)²)

Question 14

What is the Mean

Answer 14

Σx/n

Question 15

How to work out Var(x)

Answer 15

E(x²0-[E(x)]²

Question 16

How do you work out the regression constants

Answer 16

b=Sxy/Sxx

a=Mean of Y- B x Mean of x

Question 17

What is the equation of a regression line

Answer 17

y= a + bx