Week 3

Question 1

transforming X-values into Z-scores

Answer 1

• Z-score tells us the exact location of X-value
• Z-scores form a standardized distribution that can be compared to other distributions

Question 2

Z-scores

Answer 2

• sign of Z-score signifies whether score is above (+) or below (-) the mean
• number specifies the distance from the mean in terms of standard deviations

Question 3

probability (p)

Answer 3

fraction or proportion of all possible outcomes, ranges from 0 to 1
- probability of X = number of outcomes X ÷ total number of outcomes

Question 4

joint probability

Answer 4

two events occurring together is less probable than each event happening individuallyk

Question 5

conditional probability

Answer 5

how llikely something is given to that condition

Question 6

bernoulli distribution

Answer 6

applies to a discrete variable with 2 outcomes
- often one outcome is ‘success’ and the other outcome is ‘failure/no success’
- the shape of the probability distribution is determined by parameter p (= probability)

Question 7

answering probability questions about scores (X values) from a normal distribution

Answer 7

• transform the X values into z-scores
• use the unit normal table to look up the proportions corresponding to the z-score

Question 8

binomial distribution

Answer 8

shows the probability associated with each value of X from X = 0 to X = n
p = P (A) + q = P (B)
p + q = 1.00