Distributions

Question 1

What is a normal distribution?

Answer 1

The bell-shaped curve on a distribution graph.

Most scores are clusters around the mean.

The mean, median, and mode all occupy the same mid-point.

Question 2

How do you remember a negative skew distribution?

Answer 2

Left foot, negative skew. (both have ‘e’).

Mean on the left.

Question 3

How do you remember a positive skew distribution?

Answer 3

Right foot, Positive skew. (both have ‘i’).

Mean on the right.

Question 4

Outline a positive skew distribution.

Answer 4

The long tail is on the right side of the peak and the distribution scores can be said to be ‘skewed to the right’.

Thus, the mean is on the right and the mean value is higher than the value of the score at the peak of the distribution curve.

For example:
If a teacher gave students a difficult test, and as a result, most students obtained low marks and only a handful of students achieved a high mark.

Question 5

Outline a negative skew distribution.

Answer 5

The long tail is on the left side of the peak and the distribution of scores can be said to be ‘skewed to the left’.

Thus, the mean is on the left and the mean value is lower than the value of the score at the peak of the distribution curve.

For example:
If a teacher gave students an easy test, and as a result, most students obtained high marks and only a handful of students achieved a low mark.