## Thursday, November 10, 2011

### JM's Graphing Post

Bar Graph -
Advantage - best for comparing two sets of data across categories
Disadvantage - not accurate if the intervals are going up to big and you can't compare more than two sets of data

Double Bar Graph -
Advantage - best for comparing two sets of data across categories

Circle Graphs -
Advantage -best for comparing categories to the whole using percents. The sum of the percents in a circle graph is 100%.
Disadvantage - you have to figure out the percentages in the data

Line Graphs - Advantage - are best for showing changes in data overtime. Line graphs usually shows a trend.
Disadvantage - if the interval are to big apart, might not be able to see clearly

Pictograph -
Advantage - best for comparing data that can easily counted and represented using symbols
Disadvantage - not clear is less than a whole

2. How can graphs be misleading. Show 3 ways.

1. Distorting the Scale - making the break in the y axis.

2. Distorting the visuals - making the pictures in the pictograph bigger.

3. Distorting the size of bars - making 1 bar look bigger

2a) The following chart shows Pizza Sub Sales over a month. What 2 graphs would show the information accurately?

The two graphs that would show the the information accurately are bar graphs and a line graph.

2b) If you were selling Pizza Subs would you continue? How does your graph explain your answer.

I would still keep selling Pizza Subs.

The reason is that the trend is increasing.

4. Below you see 2 different examples of graphs showing healthy choices sold at the canteen. If you had to convince Mrs Mota that we should continue selling healthy choices which graph would you choose?

I would use line graph because it looks more impressive, its also really used for changes over time.

4a) Change each graph so that your information looks even MORE impressive. You may not change the data just the graphs.

Line graph - change intervals
Pictographs - represents 2 sold instead of 4