The Ranked Variable Plots show the data values for each selected variable from smallest to largest (ranked) with a selected colour ramp and size ramp to emphasise higher values as desired.
The Attribute Map on the other hand does have provision to display the values for a variable using a number of different percentile binning ranges or you can create your own custom data ranges. Rather than generating multiple plots like the Ranked Variable Plot menu option does the Attribute Map reflects the data columns used in the Attribute Manager to apply colour/shape/size to each data point in the map using up to three different variables. So to display each sample according to a 5 equal ranges binning range you just need to click on the Colour tab, select a numeric variable from the pull-down list, select a colour ramp and the binning range then click on the Auto-Attribute button. If you would like to size the data points according to the variable values as well then just select the Size tab, the variable column and click on Auto-Attribute so that the data points are both coloured and sized according to their values.