## Tuesday, November 8, 2011

### Sarah's Graphing Post

• Bar Graph

Advantages - Comparing data across categories.

Disadvantages - Can't compare two or more different sets of data and depending on the scale or interval, the exact number is not clear or can be difficult to identify.

Ex.

• Double Bar Graph

Advantages - Comparing 2 sets of data across categories.

Disadvantages - If a double bar graph has too many series of data it could be confusing to read. Also depending on the scale or interval, the exact number is not clear.

Ex.

• Line Graph

Advantages - Shows changes in data over time.

Disadvantages - Just like a bar graph,and double bar graph depending on the scale or interval the exact number is not clear.

Ex.

• Circle Graph

Advantages - Comparing categories to whole in percentage.

Disadvantage - You have to calculate the percentage of each piece of data.

Ex.

• Pictograph

Advantages - Comparing data that can easily be counted, and represented using symbols.

Disadvantages - Hard to find the exact amount of partial symbols.

Ex.

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

* Distorting the scale (break in the y-axis)

Ex.

*Distorting the visual (making a symbol appear larger than others *Pictographs only)

Ex.

*Distorting the size of the bars (making the bar wider OR make a bar appear 3-D)

Ex.

3a. The following chart shows Pizza Sub Sales over a month. What 2 graphs would show the information accurately?

Answer : A line graph, and a bar graph would show the information accurately.

3b. If you were selling Pizza Subs would you continue? How does your graph explain your answer.

Answer: I would continue selling Pizza Subs because, the Pizza Subs sold each week is increasing. A line graph would show changes in the data over time and the trend would be going up.

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?

Answer: If I had to convince Mrs.Mota that we should continue selling healthy choices, I would choose the line graph because it shows that the trend is increasing and clearly shows that people are buying more healthy foods.

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