Scree plot
Besides the view shown in figure 23.38, the result of the principal component can also be viewed as a scree plot by clicking the Show Scree Plot (
) button at the bottom of the view. The scree plot shows the proportion of variation in the data explained by each of the principal components. The first principal component accounts for the largest part of the variability.
In the Side Panel to the left, there is a number of options to adjust the view. Under Graph preferences, you can adjust the general properties of the plot.
- Lock axes This will always show the axes even though the plot is zoomed to a detailed level.
- Frame Shows a frame around the graph.
- Show legends Shows the data legends.
- Tick type Determine whether tick lines should be shown outside or inside the frame.
- Tick lines at Choosing Major ticks will show a grid behind the graph.
- Horizontal axis range Sets the range of the horizontal axis (x axis). Enter a value in Min and Max, and press Enter. This will update the view. If you wait a few seconds without pressing Enter, the view will also be updated.
- Vertical axis range Sets the range of the vertical axis (y axis). Enter a value in Min and Max, and press Enter. This will update the view. If you wait a few seconds without pressing Enter, the view will also be updated.
- Dot type Can be None, Cross, Plus, Square, Diamond, Circle, Triangle, Reverse triangle, or Dot.
- Dot color Click the color box to select a color.
- Line width Thin, Medium or Wide
- Line type None, Line, Long dash or Short dash
- Line color Click the color box to select a color.
Note that the graph title and the axes titles can be edited simply by clicking them with the mouse. These changes will be saved when you Save (
) the graph - whereas the changes in the Side Panel need to be saved explicitly.