Using The Birdwatch Project to promote Maths and ICT learning

Flight paths What skills?

Types of graphs & charts – test Answers 1Histogram7Carroll Diagram 2Pictogram8Block graph 3Table9Bar line graph 4Line graph10Venn diagram 5Tally chart11Bar chart 6Pie chart12Frequency table Click on each term for a definition. You will see that the same data can be represented in different ways. This is often a matter of personal choice, choosing a method of display that appears to demonstrate a particular feature of the data well.

Questions: What is a bar chart? What is a bar line graph / chart? Answer: A bar chart, which can also be called a bar graph, is used for representing statistical information. The lengths of the bars represent the frequencies and all the bars are of equal width. Technically, the bars can be horizontal or vertical. For discrete data, the bars should not be touching. Bar chart / Bar graphBar line graph / Bar line chart A bar line graph is very similar, but with the bars reduced in width to become lines. Note the different ways of labelling the horizontal axis. Data Handling Menu <

Question: What is a histogram? Answer: A histogram, like a bar chart, uses rectangles to represent frequency. The bars in a histogram should touch each other. They don’t all have to be the same width – the bar widths are proportional to the intervals used for the data. The other important difference with histograms is that the area of each bar represents the frequency (not the height of the bar as in bar charts). Data Handling Menu <

Question: What is a Carroll Diagram? Answer: This is a sorting diagram, named after Lewis Carroll, the author and mathematician. It is most often used to sort items with two attributes, like the example below. The sorting criteria should always be in the form ‘attribute’ or ‘not attribute’. Here the integers 1 – 20 are sorted according to the attributes Prime or Not Prime, Odd or Not Odd. Data Handling Menu < PrimeNot Prime Odd3, 5, 7, 11, 13, 17, 19 1, 9, 15 Not Odd 24, 6, 8, 10, 12, 14, 16, 18, 20

Question: What is a Venn diagram? Answer: This is a sorting diagram, named after the Yorkshire-born mathematician John Venn. The example below sorts the integers 1 – 20 according to whether they are odd and/or prime or neither (as with the Carroll Diagram example)Carroll Diagram example Data Handling Menu < Odd Prime 3, 5, 7, 11, 13, 17, Answer continued

Question: What is a Venn diagram? Answer (continued): The diagram comprises a number of circles or ellipses. The content of a circle has a particular attribute, items without the attribute are outside that circle. With only two attributes, the diagram has the same four categories as a corresponding Carroll Diagram. When additional attributes are needed, the Venn Diagram is generally simpler to draw and use. Other examples of Venn Diagrams where more than two attributes are used include: Data Handling Menu <

Question: What is a pie chart? Answer: also called a Pie diagram, presents data in proportional parts of a whole similar to slices of a pie. In the example below, the frequency for each of the children’s pets in a class is used to calculate the angles of the pie slices. There are 30 children in the class, so the angle is given by: Data Handling Menu < PetsFrequencyPie chart angle Dog560° Cat784° Fish336° Reptile448° Rabbit224° none9108° Total30360° Frequency Total X 360°, so for Cat, the angle is 7/30 x 360° = 84°

Question: What is a table? What is a frequency table? What is a tally chart? Answer: A table can be used to record data, often as it is collected. The example below is a frequency table because it records the frequencies of events/outcomes etc. The centre column shows the tally marks, used to help with the count – so this is also a tally chart. Data Handling Menu < PetsTallyFrequency Dog11115 Cat Fish1113 Reptile11114 Rabbit112 none Total30

Question: What is a block graph? Answer: This is a graph made up of blocks, often produced by children using actual blocks. In the example below, each block represents one unit but each could be used to represent a higher number provided all the blocks represent the same number of units. Data Handling Menu < PetsFreq. Dog5 Cat7 Fish3 Reptil e 4 Rabbit2 none9 Total30 Pets Frequency Dogcatfish reptile rabbitnone

Question: What is a line graph? Answer: This type of graph is created by joining the known plotted points by straight lines. Technically, the lines are not part of the graph; the lines merely indicate trends. Here is an example of a line graph. Data Handling Menu < May12 June12 July14 Aug.11 Sept. 9 Hours of sunshine x x x x x

Question: What is a pictogram? Answer: a pictogram represents the frequencies using pictures, symbols or icons. One icon can represent a frequency of 1 or a higher quantity, as indicated in the key, and fractions of the icon can be used to represent smaller quantities. Data Handling Menu <