The Frequency Plot appears at the bottom of the Cell Type widget. It provides information about how well the model is fitting the data.

At the top of the plot, the RCS value is a measure of quality of fit. Generally, values between 1 and 7 are pretty good, and higher values indicate that the model is not properly characterizing the data.
The number of events classified into each state of the progression is plotted as the frequency distribution, which will typically bounce above and below the ideal distribution shown as a straight, red line. The smoothed frequency distribution is shows an averaged distribution.
The goal is for the model to evenly distribute events in all states along the progression axis. Therefore, if the model is fitting properly, the frequency distribution will closely follow the ideal distribution horizontally. In case where the model does not match as well, the frequency distributions will show areas where they differ from the ideal significantly.

Also shown on the Frequency plot are zone boundaries for all active zones in the cell type.
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