## Thursday, April 14, 2011

### Data Handling (Histogram)

A. What is a Histogram?
histogram is "a representation of a frequency distribution by means of rectangles whose widths represent class intervals and whose areas are proportional to the corresponding frequencies."

B. How do you Plot/Draw a Histogram?
Hint: Note the following
.1 Data Range (its continuous not discrete)
.2 The x- and y- axes labels
.3 The interval of the histogram

C. Shodor histogram activity
The Shodor histogram activity allows you to change the bin size for a data set and the impact on the curve.

D. How do we analyse Histograms?
Histograms allow us to analyze extremely large datasets by reducing them to a single graph
source: http://quarknet.fnal.gov/toolkits/new/histograms.html

E. Question to PONDER and post your RESPONSES as comment
What are the differences between Histogram and Bar Graphs?

You may refer to the following links
http://mathcentral.uregina.ca/QQ/database/QQ.09.99/raeluck1.html
http://www.differencebetween.net/science/difference-between-bar-graph-and-histogram/

1. 1) A histogram presents data that is in a range while a bar chart presents data that is specific.
2) There are gaps between each bar in a bar chart but there is nor gap between each bar in a histogram.
3) The heading on he y axis is frequency and the heading on the x axis is intervals on a histogram but the headings on a bar graph may vary.

2. A histogram presents continuous data, while bar graphs present discrete data.Also there are gaps between bar graphs while histograms have none

3. A histogram represents continuous data (in a range) and the chart does not have any spaces in between data. A bar chart represents discrete data (individual) and the chart has spaces in between the data.

4. A histogram represents continuous data, while a chart us represents discrete data.
A bar chart's data is presented separately, while the data in a histogram is presented together, in sequence.
The X axis on a bar graph represents the quantity while it represents frequency in a histogram.
The Y axis on a bar graph represents the different units while it represents intervals in a histogram.

5. A histogram represents continuous data and the bar stick together while a bar graph represents discrete data and the bar is a little bit apart from each other...

6. A histogram represents continuous data.However a bar graph shows individual data.Also a histogram gives data which doesn't have spaces in between.However a bar graph has a gap in between each data provided.

7. Bar graphs show the frequency of the element in the set. They are visually depicted by the height of the bar representing the frequency of the element in the data set. However, for histogram, the data elements that are recorded and categorized, are usually numbers. Basically, these grouped elements are arranged in the visual data presentation to form an uninterrupted range of values from left to right.

8. A histogram shows continuous data while a bar graph shows discrete data.

9. A histogram displays a range of continuous data,the x and y axis on a histogram are frequency and intervals respectively.
A bar graph displays specific and discrete data, and the x and y axis are different most of the time.

10. Bar graphs are usually used to display "categorical data", that is data that fits into categories. Histograms on the other hand are usually used to present "continuous data", that is data that represents measured quantity where, at least in theory, the numbers can take on any value in a certain range.

Source: http://mathcentral.uregina.ca/QQ/database/QQ.09.99/raeluck1.html

11. A histogram's data range is continuous, unlike a bar graph, which measures discrete, therefore allowing us to measure a huge set of numbers into a single graph. It is done by measuring it in intervals, unlike the bar graph which is rather precise, requiring more space should there be a lot of numbers. Also, the x and y axes labels are much different from the bar graph, using 'frequency' and 'intervals' to label the axes.

12. the bar graph is used for displaying discrete data which also explains why they are displayed in separate "bars" which also explains the origins of the term "bar graph"....the histogram use for continuos data also uses "bars" but these are have no gap between them as they show continuos data.

13. The main difference is that the bar graph presents discreet information and a histogram presents continuous data. I think that one cannot judge which is better because they are used in different situations.

14. A bar graph shows comparisons and values and organize discrete data and information. They help show pattens and is a great tool in trying to make decisions.
A histogram is used for presenting continuous data. It is used to display frequencies and values and are grouped or categorized. It is more specific.

15. A Bar Graph presents Discrete information while a Histogram presents Continuous information.A Histogram is much more specific in giving data but a bar graph is easier to use if you want a faster conclusion.

16. The information a bar graph provides is discrete while a histrogram provides information that is continuous

17. A graphical representation which shows a visual impression of the distribution of data termed as Histogram . Histogram consists of tabular frequencies which are shown as adjacent rectangles, with an area equal to the frequency of the observations in the interval.