L7 - Large sample Confidence interval

Question 1

What is a point estimate

Answer 1

a single number is calculated from a sample and is used as a best estimate of an unknown population parameter

Question 2

what is Interval Estimation

Answer 2

Two points are placed on a real number line are used to define the range or interval for which the population parameter is thought to lie. Within a certain probability.

Question 3

what is the equation for a large sample Confidence interval

Answer 3

C.I =x̄ ± Za/2 (s/n^-1)

Question 4

what does α (alpha) represent

Answer 4

α = significance level

Question 5

what is a loose interpretation of confidence interval

Answer 5

it can be though of as a range of which events are certain to occur, over a normally distributed curve

Question 6

The appropriate sample size for a
population-based survey is determined
largely by two factors, what are they?

Answer 6

1. desired level of confidence
2. acceptable margin of error

Question 7

what Does E represent

Answer 7

Margin of error (eg, ±500

Question 8

what is the large sample confidence interval for a proportion (pi)

Answer 8

C.I = P±Za/2 * (P(1-P/n))^0.5