Skewed Distributions

Question 1

Skewed distributions can be:

Answer 1

POSITIVELY SKEWED
NEGATIVELY SKEWED
[ROUGHLY] SYMMETRICAL

Question 2

Positively skewed distribution:

Answer 2

Skewed to the right
(peaks at the left and then descends)

MEDIAN<MEAN

Question 3

Negatively skewed distribution:

Answer 3

Skewed to the left
(ascends to the peak on the right)

MEAN<MEDIAN

Question 4

[Roughly] symmetrical distribution:

Answer 4

-not directly skewed in either direction
-middle values are most common
-very low values and very high values are relatively unusual
-AKA ‘normal’ distribution/’bell curve’
(peaks roughly in the middle)
MEDIAN=MEAN

Question 5

Good practice to:

Answer 5

report the mean and median, to convey the shape of your distribution

Question 6

When people say ‘average’ they usually mean the ‘mean’, but for data that are skewed, that have extreme values in them the median is often

Answer 6

more stable