distributions

Question 1

what is a normal distribution (2)

Answer 1

symmetrical spread of data- forms a bell-shape
mean, median and mode are all located at the highest peak

Question 2

what is a skewed distribution

Answer 2

data is unsymmetrical- it is clustered at one end

Question 3

what is a positive skew (2)

Answer 3

the long tail is on the positive side of the peak (right) and most of the distribution is on the left
eg. lots of low marks on a test
-order of central tendencies (right to left):
mode->median->mean

Question 4

what is a negative skew (2)

Answer 4

the long tail is on the negative side of the peak (left) and most of the distribution is on the right
eg. lots of high marks on a test
-order of central tendencies (left to right):
mean->median->mode