Help Manual

Contents






Sigma Magic Help Version 17

Bar Chart

Overview

A bar chart can be used to graphically compare different data sets on a single chart. Bar Chart is typically used for discrete data types such as Binary, Nominal, and Ordinal.

Adding the bar chart tool to your active workbook is a breeze. Simply navigate to the Graph tab and select Bar Chart.

Inputs

Click on Analysis Setup to open the menu options for this tool.

Setup

A sample screenshot of the setup menu is shown below.
Bar Chart
1
Chart Type: Specify the format of the chart. The available options are:
FormatDescription
Bar ChartCreates a standard 2D bar chart. The categories are shown on the X-axis, and the frequencies on the Y-axis.
Bar Chart 3DCreates a 3D bar chart. You will need to specify the X and Y axis for this chart. The frequencies are shown on the Z-axis.
2
Plot Orientation: Specify the orientation for the bar chart.
FormatDescription
HorizontalPlot a horizontal bar chart.
VerticalPlot a vertical bar chart (default).
3
Data Order: Specify if the data has to be sorted before plotting it. The available options are:
FormatDescription
DefaultDo not sort the data. Plot it in the order in which it is entered.
IncreasingSort the data in increasing order before plotting it.
DecreasingSort the data in decreasing order before plotting it.
4
Data Labels: Specify if you want to display the labels for the chart.
5
Help Button: Click on this button to open the help file for this topic.
6
Cancel Button: Click on this button to discard any changes and close the dialog box.
7
OK Button: If possible, click this button to save any changes and compute the analysis outputs.

Data

You will see the following dialog box if you click the Data button. Here, you can specify the data required for this analysis. Data
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Search Data: The available data displays all the columns of data that are available for analysis. You can use the search bar to filter this list and speed up the search for the right data for analysis. Enter a few characters in the search field, and the software will filter and display the filtered data in the Available Data box.
2
Available Data: The available data box contains the list of data available for analysis. If your workbook has no data in tabular format, this box will display "No Data Found." The information displayed in this box includes the row number, whether the data is Numeric (N) or Text (T), and the name of the column variable. Note that the software displays data from all the tables in the current workbook. Even though data within the same table have unique column names, columns across different tables can have similar names.
3
Add or View Data: Click on this button to add more data to your workbook for analysis or to view more details about the data listed in the available data box. When you click on this button, it opens the Data Editor dialog box, where you can import more data into your workbook. You can also switch from the list view to a table view to see the individual data values for each column.
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Required Data: The code for the required data specifies what data can be specified for that box. An example code is N: 2-4. If the code starts with an N, select only numeric columns. You can choose numeric and text columns if the code begins with a T. The numbers to the right of the colon specify the min-max values. For example, if the min-max values are 2-4, you must select a minimum of 2 columns of data and a maximum of 4 columns in this box. If the minimum value is 0, then no data is required to be specified for this box.
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Select Button: Click on this button to select the data for analysis. Any data you choose for the analysis is moved to the right. To select a column, click on the columns in the Available Databox to highlight them and then click on the Select Button. A second method to choose the data is to double-click on the columns in the list of Available Data. Finally, you can drag and drop the columns you are interested in by holding down the select columns using your left mouse key and dragging and dropping them in one of the boxes on the right.
6
Selected Data: The list box header will be black if the right number of data columns is specified. If sufficient data has not been specified, then the list box header will be displayed in red color. Note that you can double-click on any of the columns in this box to remove them from the box.
6a
Frequency Variables: This list box contains the frequency values for each row of data specified under categorical variables. This column is not mandatory. If it is not specified, the frequency values are assumed to be 1. Note that if this column has been defined, it should contain numeric integer values. The number of rows of data in this column should match the number of rows specified in the categorical variables.
6b
Categorical Variables: This list box contains the categories to use to create the bar chart. This column is mandatory. Note that this column usually contains text. You can specify one or two columns for this analysis. If you specify two columns, the information in both columns is used to create the bar chart. In this case, you will get two levels for the legend.
6c
By Variable: This list box contains a column that can be used to create subgroups for the plots. This column is not mandatory. If you specify a column here, it should include the same number of rows of data as defined in the categorical variables. For example, if this column contains two values, "Before" and "After," then the data specified is unstacked, and two bar charts are created: one for the "Before" data and one for the "After" data.
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View Selection: Click on this button to view the data specified for this analysis. The data can be viewed in a tabular format or a graphical summary.

Charts

You will see the following dialog box if you click the Charts button. Charts
1
Title: The system will automatically pick a title for your chart. However, if you want to override that with your title, you can specify a title for your chart here. Note that this input is optional.
2
Sub Title: The system will automatically pick a subtitle for your chart. However, if you want to override that with your subtitle, specify a subtitle for your chart here. Note that this input is optional.
3
X Label: The system will automatically pick a label for the x-axis. However, if you would like to override that with your label for the x-axis, you can specify a different label here. Note that this input is optional.
4
Y Label: The system will automatically pick a label for the y-axis. However, if you would like to override that with your label for the y-axis, you can specify a different label here. Note that this input is optional.
5
X Axis: The system will automatically pick a scale for the x-axis. However, if you would like to override that with your values for the x-axis, you can specify them here. The format for this input is to specify the minimum, increment, and maximum values separated by a semi-colon. For example, if you specify 10;20, the minimum x-axis scale is set at 10, and the maximum x-axis scale is set at 20. If you specify 10;2;20, then, in addition to minimum and maximum values, the x-axis increment is set at 2. Note that this input is currently disabled, and you cannot change this setting.
6
Y Axis: The system will automatically pick a scale for the y-axis. However, if you would like to override that with your values for the y-axis, you can specify them here. The format for this input is to specify the minimum, increment, and maximum values separated by a semi-colon. For example, if you specify 10;20, the minimum y-axis scale is set at 10, and the maximum y-axis is set at 20. If you specify 10;2;20, then, in addition to minimum and maximum values, the y-axis increment is set at 2. Note that this input is optional.
7
Horizontal Lines: You can specify the values here to add a few horizontal reference lines to your chart. The format for this input is numeric values separated by semi-colon. For example, if you specify 12;15, two horizontal lines are plotted at Y = 12 and Y = 15, respectively. Note that this input is optional.
8
Vertical Lines: You can specify the values here to add a few extra vertical reference lines to your chart. The format for this input is numeric values separated by semi-colon. For example, if you specify 2;5, two vertical lines are plotted at X = 2 and X = 5, respectively. Note that this input is optional.

Verify

If you click the Verify button, the software will perform some checks on the data you entered. A sample screenshot of the dialog box is shown in the figure below. Verify The software checks if you have correctly specified the input options and entered the required data on the worksheet. The results of the analysis checks are listed on the right. If the checks are passed, they are shown as green-colored checkmarks. If the verification checks fail, they are shown as a red-colored cross. The verification checks are shown in the orange exclamation mark if the verification checks result in a warning. Finally, any checks required to be performed by the user are shown as blue info icons.
1
Item: The left-hand side shows the major tabs and the items checked within each section
2
Status: The right-hand side shows the status of the checks.
3
Overall Status: The overall status of all the checks for the given analysis is shown here. The overall status check shows a green thumps-up sign if everything is okay and a red thumps-down sign if any checks have not passed. Note that you cannot proceed with generating analysis results for some analyses if the overall status is not okay.

Outputs

Click on Compute Outputs to update the output calculations. An example screenshot of the worksheet is shown below. Bar Chart Example
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Notes: The text output of the analysis is sent to the notes section. This section contains a summary of the inputs - specifically, the number of data points, the number of distinct groups or categories in the input columns, and the orientation of the bar chart. It also contains the Analysis Results, which include the total of all the counts for each group and the groups' mode. The mode is the category that occurs the most often, and it also points to the frequency of occurrence of the mode. The software will only list the total number of modes for this data set if there are multiple modes.
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Graphs: The graphs section contains the bar chart of the given data set. If there are multiple groups, the bar chart can give a visual picture of each group's relative frequency of occurrence. The sequence in which the group appears in this graph is based on the order in which the groups appear in your data entry column.

Notes

Here are a few pointers regarding this analysis:
  • The background color of the graph can be changed by clicking the Options button in the Sigma Magic software. However, most formatting can be accomplished using standard Excel functions to format the graph. For example, you can change the layout design of the graph from vertical to horizontal using Excel. If you click on Compute Outputs again, any formatting you do with the Excel functions will be lost.
  • You can enter the data in a table format (group name and frequency) or enter the groups in a single column. Sigma Magic will automatically determine the frequency of occurrence.
  • The bar chart will skip that entire row if you have a missing group name. If the data is entered in a tabular format, any missing values in the frequency column are treated as 0.

Examples

The following examples are in the Examples folder.
  • Create a bar chart for the data file below (Product Defects.xlsx).
  • Create a bar chart for the defective soap bars, and based on your findings, what would you recommend to the company (Soap Bars Quality.xlsx)?
  • Create a bar chart for the national survey of bi-lingual operators and draw conclusions (Bilingual Phone Operators.xlsx).