Ch 2 pt 1 - Mode & Median

Question 1

Central tendency

Answer 1

Most “typical” or common score (mode, median, mean)

Question 2

Choosing a measure of central tendency

Answer 2

Consider…

1. Research question: Are there open-ended categories in the data collection?
2. Scale of measurement: for ex. it doesn’t make sense to calculate mean for nominal, ordinal, or discrete data)
3. Shape of distribution: is it symmetric or skewed?

Question 3

Mode

Answer 3

Most frequently occurring number in a distribution

The only measure of central tendency for nominal variables

The highest peak in a graph is the mode

There can be one mode, bimodal or multimodal (major & minor mode)

Question 4

Limitations of Mode

Answer 4

Only measure of CT for nominal data. It’s often preferred for discrete variables.

Fluctuates easily (minor fluctuations in data can change it substantially

Principal use is informal; commonly used to describe the shapes of distribution

gives the least info; not the primary choice if other measures of tendency are available.

Question 5

Median

Answer 5

value in a data set that divides the distribution in half

When values are ordered from low to high, the median is used to describe the midpoint of a distribution.