Statistics - Test 3

Question 0

discrete random variable

Answer 0

assumes countable values in an interval and nothing in between
- # of pets, # of cars

Question 1

continuous random variable

Answer 1

assumes any value in one or more intervals

- weight, length of room

Question 2

characteristics of normal distribution

Answer 2

1. total area under the curve is 1
2. curve is symmetric about the mean
3. the two tails of the mean extend indefinitely

Question 3

parameters of the normal distribution

Answer 3

mean (μ) & standard deviation (σ)

Question 4

z-score

Answer 4

• units marked on the horizontal axis of the standard normal curve
• denoted by z
• specific value of z gives the distance between the mean and the point z in terms of standard deviation

Question 5

properties of discrete random variables

Answer 5

1. 0 <_ 1 for each x

2. ΣP(x) sum of all probabilities is 1

Question 6

properties of continuous random variables

Answer 6

1. the probability that x assumes a value in any interval is between 0 and 1
2. the total probability of all intervals is 1

Question 7

characteristics of the standard normal distribution

Answer 7

μ = 0
σ = 1