Distributions of data

Question 1

What is distribution of data?

Answer 1

The distribution of data is simply a way of showing how data values are spread out or organized

Question 2

Frequency distribution

Answer 2

Characterizes the data from your sample

Question 3

Probability distribution

Answer 3

Allows for using current data to predict distribution of new data points

Question 4

DISTRIBUTION SHAPE IS CHARACTERIZED BY “MOMENTS” - what 4 moments?

Answer 4

1. First moment = Mean (central tendency)
2. Second moment = Variance (width or deviation of distribution)
3. Third moment = Skewness (asymmetric tendencies towards one tail or other)
4. Fourth moment = Kurtosis (indicates how large the tails of a distribution are relative to
   the rest of distribution [‘peakiness’])
   (Third and fourth moments are typically investigated to assess deviations from normality.)

Question 5

A normal distribution - how is it characterized?

Answer 5

Perfectly symmetrical around its mean, the mean (average), median (middle value), and mode (most frequent value) are all the same and located at the center of the distribution, the curve is bell-shaped, no skewness or kurtosis