Charts and Graphs

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"A picture is worth a thousand words." This is certainly true when you're presenting and explaining data. You can provide tables setting out the figures, and you can talk about numbers, percentages, and relationships forever. However, the chances are that your point will be lost if you rely on these alone. Put up a graph or a chart, and suddenly everything you're saying makes sense!

Graphs or charts help people understand data quickly. Whether you want to make a comparison, show a relationship, or highlight a trend, they help your audience "see" what you are talking about.

The trouble is there are so many different types of charts and graphs that it's difficult to know which one to choose. 

To figure out what orders to give, you need to have a good understanding of the mechanics of charts, graphs and diagrams. We'll show you the basics using four very common graph types:

• Line graph
• Bar graph
• Pie chart
• Venn diagram
• Histrogram

•  A bar graph is composed of discrete bars that represent different categories of data. The length or height of the bar is equal to the quantity within that category of data.  Bar graphs are best used to compare values across categories. 

• A pie chart is a circular chart used to compare parts of the whole.  It is divided into sectors that are equal in size to the quantity represented.
• As such it shows a percentage distribution. The entire pie represents the total data set and each segment of the pie is a particular category within the whole.

• A line graph displays the relationship between two types of information, such as number of school personnel trained by year.  They are useful in illustrating trends over time. 
• Line graphs simply use a line to connect the data points that you plot. They are most useful for showing trends, and for identifying whether two variables relate to (or "correlate with") one another.

• A histogram has connected bars that display the frequency or proportion of cases that fall within defined intervals or columns.  The bars on the histogram can be of varying width and typically display continuous data.

• The last graph we will cover here is the Venn diagram. Devised by the mathematician John Venn in 1881, this is a diagram used to show overlaps between sets of data.
• Each set is represented by a circle. The degree of overlap between the sets is depicted by the overlap between circles. 

I have found a very good examples analysis graph chart essays

You can click here to see the examples

• http://www.scribd.com/doc/3049082/IELTS-Writing-Task-1-Graph-Part-II

I hope this will helps you :)

Good luck !

By : K vany