<< Click here to display Table of Contents >> Navigation: Analysis of Flow and Image Cytometry Data Files > Statistics:

Histogram Statistics

Contents

Statistics will be calculated for every overlay on the histogram. If there are markers, statistics will be calculated for every overlay that the marker applies to (see Creating Markers and Histogram Markers).

To view the histogram statistics, right-click on the plot and select Histogram Statistics from the pop-up menu (Figure 9.54 below, ). Individual statistics may be toggled on and off by right-clicking on the default statistics table (Figure below, ), or from the Formatting Statistics menu.

Figure 9.54 Adding a default statistics table from a histogram

The available statistics are shown in the table below.

Statistic	Explanation
Histogram #	If there are multiple overlays visible on a plot, then the statistics will be calculated for every overlay. Histogram # displays the overlay number for that row of statistics. The overlay number corresponds to the position in the overlay list on the Overlays page of the Format window.
Filename	The file name of the overlay.
Parameter	The parameter name for the parameter that is being displayed on the overlay. The field that the parameter name is taken from can be set in the FCS Express User Options Dialog under Data Loading - FCS File Options.
Overlay Gate	The name of the gate that is currently being applied to the overlay.
Marker	If there are several markers visible on a plot, then the statistics will be calculated for each overlay that the marker applies to. Marker displays the marker number for that row of statistics. The marker number corresponds to the position in the marker list on the Markers page of the Format window (see Histogram Markers).
Low bound	The channel number of the low boundary of the marker.
High bound	The channel number of the high boundary of the marker.
# of Events	The number of events that are accepted by the gating formula.
% of all cells	The number of events that are accepted by the gating formula and are located within the specified marker divided by the total number of events in the FCS file.
% of gated cells	The number of events that are accepted by the gating formula and are inside the specified marker divided by the total number of events displayed on the plot.
Median	The median channel value of the events that are accepted by the gating formula that fall within the specified marker.
Geometric Mean	The geometric mean channel number of the events that are accepted by the gating formula that fall within the specified marker. Similar to arithmetic mean except that the numbers are multiplied and the Nth root of the resulting product is taken.
Arithmetic Mean	The arithmetic mean channel number of the events that are accepted by the gating formula that fall within the specified marker.
CV (Coefficient of Variation)	The coefficient of variation of events that are accepted by the gating formula that fall within the specified marker. The CV is a measure of the distribution of your data and is equal to the standard deviation divided by the mean.
RCV (Robust CV)	The Robust Coefficient of Variation of events that are accepted by the gating formula. The RCV may be more applicable than the CV for populations that do not follow a normal Gaussian distribution. The RCV is equal to 0.75 multiplied by the interquartile range divided by the median. The interquartile range is the 75th percentile channel minus the 25th percentile channel.
5%-ile(5th percentile)	The channel corresponding to the 5th percentile of the cells that have been accepted by the gating formula.
95%-ile (95th percentile)	The channel corresponding to the 95th percentile of the cells that have been accepted by the gating formula.
25%-ile (25th percentile)	The channel corresponding to the 25th percentile of the cells that have been accepted by the gating formula.
75%-ile (75th percentile)	The channel corresponding to the 75th percentile of the cells that have been accepted by the gating formula.
Concentration	The concentration of the cells that are accepted by the gating formula. The parameters for the concentration calculation can be set up in the Concentration Calculator.
Percent Positive	The percentage of the cells accepted by the gating formula that are positive with respect to the control overlay. The control overlay is set in Histogram Specific Options. The Overton Subtraction method statistic will be displayed.
Standard Deviation	A measure of the variation from the average for the events. The square root of the variance.
% of gated - parent	The number of events that are accepted by the gating formula and are inside the specified marker divided by the total number of events in the parent gate.
% of gated - grandparent	The number of events that are accepted by the gating formula and are inside the specified marker divided by the total number of events in the grandparent gate.
BD-rSD	The BD Biosciences robust standard deviation. See the full description by BD Biosciences.
BD-rCV	The BD Biosciences robust coefficient of variation of events that are accepted by the gating formula that fall within the specified marker. See the full description by BD Biosciences.

The right-click→ Format pop-up menu→ Markers→ If there are markers on plot, also show statistics for the base overlay without the marker checkbox is for displaying statistics for the entire overlay with no marker applied.