Home / Statistical Tools / Analysis Tools / Dotplot / Examples / GroupBy
GroupBy¶
Use GroupBy to create separate dot plot charts for each group in your data, making it easy to compare distributions across shifts, departments, or locations.
Goal¶
Compare measurement distributions between Day and Night shifts to see whether one shift produces more variable results than the other.
Sample Data¶
Excel Protected View
When you open downloaded files, Excel displays a Protected View warning. You must click Enable Editing before you can use Quantum XL with the file.
Alternatively, you can copy the sample data from the table below and paste it directly into a new Excel workbook.
| Measurement | Shift |
|---|---|
| 24.2 | Day |
| 24.5 | Day |
| 24.8 | Day |
| 25.0 | Day |
| 25.1 | Day |
| 25.3 | Day |
| 25.5 | Day |
| 25.5 | Day |
| 25.8 | Day |
| 26.0 | Day |
The table shows the first 10 of 24 rows. Download the full dataset above for the complete example. Day shift has 12 observations and Night shift has 12 observations.
Steps¶
-
Launch the analysis
From the Excel ribbon, select QXL Stat Tools → Analysis Tools → Dot Plot.
-
Select your data
Select cells A1:B25 (the header row plus all 24 data rows).
-
Configure the analysis
In the Dot Plot dialog:
- Select the GroupBy radio button (instead of Excel)
- Data Columns: "Measurement" should be checked, "Shift" should be unchecked
- GroupBy: Move "Shift" to the GroupBy Order list
Click Finish to generate the charts.
How GroupBy Works
When you add a GroupBy column, Quantum XL creates a separate chart for every unique value in that column. In this example, the "Shift" column has two unique values — "Day" and "Night" — so we get two charts.
Result¶
Quantum XL creates two dot plot charts, one for each shift:
Day Shift — Twelve measurements tightly clustered between 24.2 and 26.5, showing a very consistent process.
Night Shift — Twelve measurements spread from 27.0 to 36.0, with a wider distribution and a higher center. The isolated dot at 36.0 stands out from the main group.
The two charts make it easy to see that the Night shift produces higher and more variable measurements than the Day shift.