Chap 20 - Histograms, frequency density, cumulative frequency Flashcards
1
Q
how to draw a histogram
A
-bar chart without gaps
-frequency on y axis, stuff on x axis
2
Q
how to do frequency density
A
frequency/ class width
3
Q
how to draw frequency density histogram
A
-if diff sized classes, find frequency density
-histogram without gaps
-diff. sized bars
4
Q
how to do cumulative frequency drawing
A
-line graph starting from 0
-dots at end of the class interval
-frequency adds up
5
Q
how to find mean, UQ, LQ, IQR
A
-find middle of frequency & check on graph for that frequency
5
Q
why is IQR better than range
A
it shows where 50% of the data lies
6
Q
what percentile is LQ, IQR, UQ
A
LQ- 25%
IQR- 50%
UQ-25%
