I am trying to make an equal interval legend using a rate of burglaries per 1000 habitants using a combination of a column with the counts of burglaries and a column of total population using census districts. Due to the fact that there are outliers in the data (extremely high values) I would like to exclude them from the process of defining classes in the legend based on a threshold of the total population (less than 700). I already build a expression in the expression function (which exclude values <700) window like this:
CASE WHEN "burglaries_CS_POPN_2000|2000" >= 700 THEN ( "burglaries_P500_ALL|2009" / "burglaries_CS_POPN_2000|2000" ) END
It works fine, but the polygons excluded are not showed anymore. In ArcGis there is an option for "show symbol for excluded data" in the symbology-classification window. Is there an option in QGIS that could perform the same task without adding a new column in the attribute table? Could it be done using an expression like I show above?