quiz 2 equations and material

Question 1

when sample increases and p^ decreases

Answer 1

p^ is more precise

Question 2

standard deviation of p^

Answer 2

sqrt(p^q^/n)

Question 3

what should n be for maximum according to central limit theorem

Answer 3

• as n increases the distribution of x^ will approximate a normal distribution
• sample should be big enough for the normal to be reliable
• n>/= 30 is often considered large enough for CLT

Question 4

n increase with standard deviation decreases

Answer 4

making it more concentrated around the mean

Question 5

interpret your CI

Answer 5

w/ ___% confidence you can say the difference in averages is (lower bound) and (upper bound)

Question 6

if 0 is not within CI interval

Answer 6

• likely means the means aren’t the same
• there is a difference between situation 1 and situation 2

Question 7

point estimator

Answer 7

p^1-p^2

Question 8

SE

Answer 8

sqrt(p1q1/n1+p2q2/n2)

Question 9

ME

Answer 9

1.96SE

Question 10

what might you conclude

Answer 10

that since the probability of p^ (what u measured) is (ex) less than 0.2% the sample info casts doubt on the original claim (ex)

Question 11

mean of p^

Answer 11

=p

Question 12

z for p^

Answer 12

p^-u/standard deviation

Question 13

the formula with p^ and zalpha/2 stuff

Answer 13

p^+/-z(sqrt p^q^/n)

Question 14

the equations for sample size and what not

Answer 14

n >/= [z/B]^2 (p1q1 +p2q2)