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Charting User Guide

The Charting tool has been developed as an easy to use resource with which you and your students can quickly explore a range of statistical calculations and graphs from small data sets.

It is not intended to handle large data sets for which other ICT resources are more appropriate. It is not possible to import data from other software or data loggers in to this version of the Charting tool software.

The environment will support a range of thinking skills which underpin rich mathematical activities and will help students to:

interpret and compare a range of statistical graphs and calculations
explore box and whisker plots produced from data sets
make and test conjectures

for example, what would happen to the mean average of a set of data if all of the data values are increased by 1?

explore independently the relationships within and between numbers in data sets

Entering data

When you open the Charting tool, you will be prompted to enter a set of data.

Select Add Row to input data.

A maximum of two lists (in two columns) and 15 rows can be added.

The data sets can be defined as Raw data if the two lists contain data which is to be compared in some way. Depending on the context, the data in each list may be linked, for example to explore correlation or be from different sources for comparison.

If two lists of data are to be compared, they will need to be the same length.

For example, the data here shows the wrist and neck circumferences for 15 female adults.

With the data entered, if you select Show statistics, the minimum, maximum, mean and median values for the data can be revealed and hidden.

Alternatively, in the following example, Lists 1 and 2 contain the frequencies for two groups of students’ ways of getting to school.

The Label Name column can be used to add text that is relevant to the data. This text will appear as labels on Bar charts and Pie charts.

If the data is defined as Frequency data , List 1 will contain the data value, which could be the mid-value for a grouped data set, and List 2 would contain the frequencies.

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The example here represents the total score when a pair of ordinary dice is thrown 100 times.

Again, by selecting Show statistics, the minimum, maximum, mean and median values for the data can be revealed and hidden.

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Drawing statistical charts

There are a range of statistical graphs that can be drawn; however, depending on the nature of the data that is entered the Charting tool will handle it in different ways.

Working with raw data

List 1 and List 2 would need to contain data that is to be compared in some way. The type of graphs that would 'make sense' would depend on the data in the lists.

For example, to compare two Bar charts or Pie charts, each list would need to contain frequencies, whereas to compare two Box and whisker plots, each list would need to contain the actual data values.

A Scattergram could be used to explore if two sets of data in List 1 and List 2 could be correlated.

Graph type

Definition

Example

Bar chart

A Bar chart representing the data in List 1 or List 2 will be drawn.

The values are shown in the order they appear in each list with the heights equal to each data value.

If List 1 contains the numbers of students travelling to school by different modes of transport.

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Pie chart

A Pie chart representing the data in List 1 or List 2 will be drawn.

For the Pie chart to make sense, the lists would need to contain frequency data.

If List 2 contains the numbers of students travelling to school by different modes of transport.

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Box and Whisker

A Box and whisker plot representing the data in List 1 or List 2 will be drawn.

For the Box and whisker plot to make sense, the lists would need to contain the actual data values.

If List 1 contains 15 students’ usual journey time to school in minutes.

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Scattergram

A Scattergram of the data in List 1 (x axis) and List 2 (y axis) is plotted.

The data points are numbered on the graph.

If List 1 contains data relating to female adult wrist measurements in centimetres and List 2 the neck measurements for the same person.

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Working with frequency data

If the data represents frequency data, List 1 should contain the data values (or mid-values of grouped data), and List 2 should contain the frequencies.

Graph type	Definition	Example
Bar chart	A simple Bar chart will be drawn with the values shown in the order they appear in List 1 with heights equal to the values in List 2. The colours correspond to each row of the data in the table.	For the dice data, List 1 contains the dice totals and List 2 the frequencies.
Pie chart	The Pie chart will be drawn with the sections in a clockwise order. The colours correspond to each row of the data in the table. As you move the cursor over each part of the Pie chart, the angle and the percentage of the Pie chart that segment represents is displayed.	For the dice data, List 1 contains the dice totals and List 2 the frequencies.
Box and whisker plot	The Charting tool will interpret the tabulated frequency data and display the Box and whisker plot.	For the dice data, List 1 contains the dice totals and List 2 the frequencies.
Frequency graph	The frequency graph will be plotted as coordinate points represented by the numbers in List 1 (x axis) and List 2 (y axis).	For the dice data, List 1 contains the dice totals and List 2 the frequencies.

Load Data

Pressing the load data button will load in any points that were transferred across from the graphing section of the toolkit (by selecting Transfer to charting from the File menu). These will be displayed in a table in the chart data pane and can be used to draw charts like those seen above.