Stats - normal and binomial distribution

Question 1

Describe the features of a normal distribution

Answer 1

bell shaped

symmetrical about the mean (mean = median = mode)

asymptotes at each end

area under curve = 1

points of inflection at μ + σ and μ - σ

Question 2

what is the critical region?

Answer 2

if the test statistic falls within this region, it would lead you to reject the null hypothesis

Question 3

what is a critical value?

Answer 3

the first value to lie in the critical region

Question 4

what must you remember to do with the significance level when you have a two tailed test?

Answer 4

halve the significance level

Question 5

how do you calculate the actual significance level for a binomial hypothesis test?

Answer 5

find the probability of the test statistic falling in the critical region, given that the null hypothesis is true

Question 6

conditions for binomial distribution

Answer 6

1. Fixed number of trials 2. Events are independent 3. Two possible outcomes 4. Probability of each outcome is fixed

Question 7

what is a test statistic?

Answer 7

the result of the experiment or the statistic that is calculated from the sample

Question 8

what is the p-value?

Answer 8

the probability of observing the test statistic or more extreme

Question 9

when can we use the normal distribution to approximate a binomial distribution?

Answer 9

when n is very large and p is close to 0.5

Question 10

how can you use the standard normal distribution to find the crtitical region in a normal distribution hypothesis test?

Answer 10