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In this video, we show how to create tabular summaries for the Impurity data. We use Tabulate to create summary statistics for Impurity for the different reactors and shifts.
First, we select Tabulate from the Analyze menu. You can drag and drop variables and statistics to the different drop zones. There is a drop zone for columns and a drop zone for rows. The resulting cells panel is also a drop zone.
Here, we want to calculate the mean and the standard deviation for Impurity for each of the reactors and shifts.
We drag Impurity to the Drop zone for columns. Before we drop Impurity in this zone, notice that there is a blue rectangle when we place the cursor on the drop zone. In fact, as we drag Impurity over the table, you see that there are many drop zones. These blue rectangles provide guidance as you build your tabular summary.
We drop Impurity on the Drop zone for columns, and then we drag Reactor to the Drop zone for rows. The default statistic, which displays in the resulting cells panel, is the sum.
Finally, we drag Mean and Std Dev and drop them on Sum. This replaces the sum with these two statistics.
To add the mean and standard deviation for each shift to this table, we drag and drop Shift below the table.
Let’s take a look at the statistics for each variable. The mean for reactor 3 is higher than the mean for the other reactors, and the standard deviation is also higher. But there isn’t much difference in either the mean or the standard deviation for the two shifts.
As a last step, we click Done to close the control panel.
