Data

Question 1

What are measures of dispersion?

Answer 1

Standard deviation, Interquartile range and range.

Question 2

Advantages and disadvantages of standard deviation.

Answer 2

Adv.
Uses all data from sample.
Is less affected by outliers.
Tells us how the data varies.
Can understand where an individual score lies in relation to the rest.
Disadv.
Much more difficult if the data is skewed.
Harder to calculate than the range.

Question 3

What are the four levels of measurement?

Answer 3

NOMINAL/CATEGORICAL - different categories (eg height, hair colour etc.)
ORDINAL - rank order (more precise than nominal)
SAFE - when data is measured on a scale with equal intervals (objective)
UNSAFE - when data is measured in a subjective scale (ordinal)

Question 4

When do we use the sign test?

Answer 4

When the DV is ordered nominally.
When it is a repeated measures or matched pairs design.
When they are testing for a difference between conditions.

Question 5

What are the measures of central tendency?

Answer 5

Mean, median, mode.