1 | Data Type:
Specify the type of data for which you want to create the control chart. The type of control chart created depends on the type of data entered. The available options are:
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2 | Input Type:
Specify how the input data for this analysis is formatted. The available options are:
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3 | Chart Type:
Specify the control chart you want to create. If you specify "Auto" then the software will automatically pick a chart based on your inputs. If you specify pre-control as the control chart then instead of estimating the control limits, the control chart is based on the specification limits. For a pre-control chart, there are three zones. If any data points exceed the specification limits, they are in the red zone. In addition to the control limits, pre-control limits are plotted on the chart. If data points fall within the pre-control limits, they are in the green zone and between the pre-control limits and the control limits, they are in the yellow zone. The following charts are available in this module:
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4 | Parameter:
Some of the control charts require a design parameter to compute the control limits. The following parameters are required:
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5 | Subgroup Type:
Specify how you want to enter subgroup information. The available options are:
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6 | Subgroup Constant: If you specify that the subgroup is constant, then you will need to enter the constant subgroup size in the input dialog box. Make sure that the subgroup constant is an integer greater than 0. | ||||||||||||||||||
7 | X Axis:
Specify the type of X-axis you would like for the control chart. The available options are:
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8 | Stages: Specify if you want to plot the control chart by stages. If you don't have any stages, all the data points are plotted together. If your data has stages, then each stage is treated as one entity and control charts are created for each stage. You can have any number of stages on your control chart. If you specify that you have stages, then the software will display the stage column in the Inputs area on the worksheet and you can specify the sages in the data (for example before & after improvement). | ||||||||||||||||||
9 | Flowchart: Click on this button to view the flowchart for this analysis. The flowchart shows the control logic for how a test is selected based on the data type and subgroup size when the auto mode is selected for control charts. | ||||||||||||||||||
10 | Help Button: Click on this button to view the help file for this topic. | ||||||||||||||||||
11 | Cancel Button: Click on this button to discard the changes and exit the dialog box. | ||||||||||||||||||
12 | OK Button: Save changes and try to compute analysis if all the required data is available for analysis. |
1 | Data Type: The data type in the discrete case would read either Defects of Defectives. | ||||||||||||||||
2 | Input Type: For discrete data, this input box is disabled since there is only one option allowed - Group Data. | ||||||||||||||||
3 | Chart Type:
If you change the data type to Defects Data then only those charts that are applicable for defects data are shown in this dropdown box. In this case, the available options are:
If you change the data type to Defectives Data then the charts that are applicable for defectives data are shown in the dropdown box. In this case, the available options are:
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4 | Subgroup Constant: For discrete data, the subgroup constant refers to the total number of samples in the subgroup. Use this only if the subgroup size is constant. If your subgroup size is variable, you will need to change the subgroup type to Variable and the data you enter in the Data tab will be used to determine the subgroups and the Subgroup Constant field will be disabled. |
1 | 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 to speed up finding the right data to use 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 does not have any 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. Hence, it is important that you not only specify the column name but also the table name. | ||||||||||
3 | Add or View Data: Click on this button either to add more data into 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 up the Data Editor dialog box where you can import more data into your workbook, or you can switch from the list view to a table view to see the individual data values for each column. | ||||||||||
4 | 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, then you will need to select only numeric columns. If the code starts with a T, then you can select both numeric and text columns. The numbers to the right of the colon specify the min-max values. For example, if the min-max values are 2-4, then you need to select a minimum of 2 columns of data and a maximum of 4 columns of data in this box. If the minimum value is 0, then no data is required to be specified for this box. | ||||||||||
5 | Select Button: Click on this button to select the data for analysis. Any data you select 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 select the data is to double click on the columns in the list of Available Data. Finally, you can also 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:
If the right amount of data columns has been specified, the list box header will be displayed in the black color. If sufficient data has not been specified, then the list box header will be displayed in the red color. Note that you can double-click on any of the columns in this box to remove them from the box. The data you have to select for this exercise depends on the options you specify in the dialog box. The following options are available:
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7 | View Selection: Click on this button to view the data you have specified for this analysis. The data can be viewed either in a tablular format or in a graphical summary. |
1 | Control Limits:
Specify how you want to determine the control limits. The following options are available:
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2 | Test for Special Causes:
Determine what tests you want to perform to check if your process is in control. The following options are available.
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3 | Include Points:
Specify what groups should be included to calculate the control limits. If you leave this field blank, then all subgroups available in your input columns will be used to calculate the control limits. If you want to include only certain groups, you need to specify the groups. For example, if you want the first 20 groups to be used to calculate control limits, specify the include as 1-20. If you want to include groups from 1-20 and 22-25 (that does not include group 21), then you would specify it as 1-20;22-25. Note that for some cases you may not have the option of specifying the Include Points for analysis. In those cases, the textbox will change so that you can specify other options for analysis. For example, if you are creating a CUSUM control chart, then this option will change and you will be asked to enter the Slack (K) variable. The slack variable is used to determine the mean-shift for the control chart and the default value is 0.5. If you are creating a Pre Control chart, then this option will change to an LSL/LB value and you will need to specify the Lower Control Limit or the Lower Bound for your analysis. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
4 | Exclude Points:
Specify what groups you would like to exclude in calculating the control limits. For example, if you specify exclude as 21;26;27 then these specific groups (21, 26, and 27) will not be used to calculate the control limits. For example, if include groups are blank and exclude groups contain 22, then all groups are included to calculate the control limits except group 22. If the include groups contain 1-30 and exclude groups contain 22, then the groups used to compute the control limits are 1-21 and 23-30. Note that for some cases you may not have the option of specifying the Exclude Points for analysis. In those cases, the textbox will change so that you can specify other options for analysis. For example, if you are creating a CUSUM control chart, then this option will change and you will be asked to enter the Limits (H) variable. The limits variable is an option for the CUSUM chart to determine how to compute the control limits. The default value is 4. If you are creating a Pre Control chart, then this option will change to a USL/UB value and you will need to specify either the Upper Control Limit or the Upper Bound for your analysis. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
5 | Test:
When you change the test in the "Test for Special Causes", the correponding test limits are shown on the dialog box. Note, that you can only view the standards for AIAG, Basic, Montgomery, Nelson, Western, and Westgard. If you want to define your standards, you can modify the value of K for the Custom tests. Modify this with caution since these values have been derived from probability theory and should not be changed unless there is a strong reason to make a change. Here are the tests that are currently available within the software for the standard control charts.
For the pre-control charts, the tests for special causes are shown in the following table:
For a pre-control chart, for pre-qualification of the process set up, we require five consecutive data points that should fall in the green zone. If any data point falls in the yellow or red zone, then the counting is restarted until there are five consecutive data points are in the green zone. Note that for pre-control charts, if you specify "Basic", then only test #1 will be performed otherwise all the pre-qualification tests will be performed. |
0 | Pick Charts: Select the charts you would like to display for this analysis. |
1 | Title: The system will automatically pick a title for your chart. However, if you would like to override that with your own 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 would like to override that with your own subtitle you can 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 own 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 own 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 then 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 optional. |
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 then the minimum y-axis scale is set at 10 and the maximum y-axis scale 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: If you want to add a few extra horizontal reference lines on top of your chart you can specify the values here. The format for this input is numeric values separated by semi-colon. For example, if you specify 12;15 then two horizontal lines are plotted at Y = 12 and Y = 15 respectively. Note that this input is optional. |
8 | Vertical Lines: If you want to add a few extra vertical reference lines on top of your chart you can specify the values here. The format for this input is numeric values separated by semi-colon. For example, if you specify 2;5 then two vertical lines are plotted at X = 2 and X = 5 respectively. Note that this input is optional. |
1 | Subgroup From: If you leave this textbox blank, then the charts will display from the first subgroup. However, if you want to focus on a part of the graph, you can enter a starting subgroup number in this textbox. All subgroups below this value will be excluded from the control chart. Note that this is only for display purposes and these points will continue to be used for other analysis such as to determine control limits etc. |
2 | Subgroup To: If you leave this textbox blank, then the charts will display all the subgroups until the last subgroupo. However, if you want to focus on a part of the graph, you can enter an ending subgroup number in this textbox. All subgroups above this value will be excluded from the control chart. Note that this is only for display purposes and these points will continue to be used for other analysis such as to determine control limits etc. |
3 | Chart 1 Min: You can specify the minimum value for the Y-axis for Chart 1. If you leave these fields blank, the software will automatically pick the best possible values for this chart. However, if a value is specified here, it will override the automated selection. |
4 | Chart 1 Max: You can specify the maximum value for the Y-axis for Chart 1. If you leave these fields blank, the software will automatically pick the best possible values for this chart. However, if a value is specified here, it will override the automated selection. |
5 | Chart 2 Min: You can specify the minimum value for the Y-axis for Chart 2. If you leave these fields blank, the software will automatically pick the best possible values for this chart. However, if a value is specified here, it will override the automated selection. |
6 | Chart 2 Max: You can specify the maximum value for the Y-axis for Chart 2. If you leave these fields blank, the software will automatically pick the best possible values for this chart. However, if a value is specified here, it will override the automated selection. |
7 | Chart 1 LB: You can specify a lower bound for Chart 1. If the LCL calculated is higher than the lower bound value, then no action is taken. However, if the LCL value of the chart is less than the lower bound value, then the LCL value is replaced by the lower bound value. |
8 | Chart 1 UB: You can specify a upper bound for Chart 1. If the UCL calculated is lower than the upper bound value, then no action is taken. However, if the UCL value of the chart is greater than the upper bound value, then the UCL value is replaced by the upper bound value. |
9 | Chart 2 LB: You can specify a lower bound for Chart 2. If the LCL calculated is higher than the lower bound value, then no action is taken. However, if the LCL value of the chart is less than the lower bound value, then the LCL value is replaced by the lower bound value. |
10 | Chart 2 UB: You can specify an upper bound for Chart 2. If the UCL calculated is lower than the upper bound value, then no action is taken. However, if the UCL value of the chart is greater than the upper bound value, then the UCL value is replaced by the upper bound value. |
11 | Stdev 1: You can superimpose the 1-stdev lines on the control chart by selecting this checkbox. Note that by default, only the 3-stdev lines are shown on the control chart. |
12 | Stdev 2: You can superimpose the 2-stdev lines on the control chart by selecting this checkbox. Note that by default, only the 3-stdev lines are shown on the control chart. |
1 | Pick Point: Click on this button to pick a point on the control chart that you want to annotate. Note that if you click on a data point the first time, it may pick all the points. If this is the case you may need to click on the data point a second time to only pick that one point for annotation. |
2 | Point Num: When you click on a point from the previous step, it should automatically list the point that was selected in this dropdown box. If not, you can manually select or type in the point in this box. |
3 | Chart Num: When you select a point, the chart number should automatically be displayed here. If not, you can specify the chart that you want to annotate. |
4 | Add Text: Enter a text that you want to use for the annotation in this textbox. |
5 | Delete Text: Click on this button to delete any point that was previous selected for annotation. |