Teaching:TUW - UE InfoVis WS 2007/08 - Gruppe 07 - Aufgabe 1 - Histogram: Difference between revisions
Jump to navigation
Jump to search
No edit summary |
No edit summary |
||
| Line 18: | Line 18: | ||
| || ||<b>Σ 600</b> || <b>Σ 1,00</b> || | | || ||<b>Σ 600</b> || <b>Σ 1,00</b> || | ||
|}<br /> | |}<br /> | ||
<b>Frequency density</b> (height of a column)= n <sub> j </sub> / w <sub> j </sub> | <b>Frequency density</b> (height of a column) = n <sub> j </sub> / w <sub> j </sub> | ||
= Related Links = | = Related Links = | ||
Revision as of 18:14, 1 November 2007
Definitions
In statistics, a histogram is a graphical display of tabulated frequencies. A histogram is the graphical version of a table that shows what proportion of cases fall into each of several or many specified categories. The histogram differs from a bar chart in that it is the area of the bar that denotes the value, not the height, a crucial distinction when the categories are not of uniform width (Lancaster, 1974). The categories are usually specified as non-overlapping intervals of some variable. The categories (bars) must be adjacent.
[Wikipedia, 2007]
Example
Frequency Table (Salary of Employees):
| class j | Salary x i | absolute frequency n j | relative frequency | class width w j |
|---|---|---|---|---|
| 1 | 800 ≤ x < 1000 | 150 | 0,25 | 200 |
| 2 | 1000 < x < 2000 | 150 | 0,25 | 1000 |
| 3 | 2000 ≤ x ≤ 3500 | 300 | 0,50 | 1500 |
| Σ 600 | Σ 1,00 |
Frequency density (height of a column) = n j / w j
Related Links
References
- [Wikipedia, 2007] Wikipedia, Histogram. Retrieved at: November 01, 2007. http://en.wikipedia.org/wiki/Histogram