Chapter 2- Frequency Distributions: Textbook

Question 1

frequency distribution

Answer 1

• an organized tablation of the number of individuals located in each category on the scale of measurement
• allows you to see the location of any individual score relative to all the other scores in the set

Question 2

percentile rank

Answer 2

refers to a percentage

Question 3

percentile

Answer 3

a score

Question 4

Grouped frequency table guidelines

Answer 4

1. There should be around 10 class intervals
2. The width of each interval should be a relatively simple number
3. The bottom score of each interval should be a multiple of the width
4. All intervals should have the same width

Question 5

The wider the class interval for a grouped frequency distribution…

Answer 5

…the more information that is lost

Question 6

apparent limits

Answer 6

In a class interval (ex. 30-40) the apparent limits are 30-40, but the real limits are 29.5-40.5

Question 7

The Y axis should be…

Answer 7

…2/3 to 3/4 of its’ length

Question 8

Histogram width:

Answer 8

• should extend exactly half the distance to the adjacent category on each side (discrete variables)
• should extend to the real limits of the category (continuous variables)

Question 9

Where should the dots for polygons be placed if the data is grouped into class intervals?

Answer 9

• at the midpoint of the class interval
• (ex. 10-19=14.5)

Question 10

relative frequency vs. absolute frequency

Answer 10

• absolute frequency is a normal frequency, telling us the number of times something has occured
• relative frequency is a propotion between a value and the total