1. A method for determining ethnicity of people based on their facial images captured by at least a means for capturing images for a target person, comprising the following steps of: a) forming image filter groups in a plurality of image filters, b) computing filter responses by applying the image filters to facial images from an ethnicity-annotated facial images database, c) computing joint histograms of the filter responses within each filter group, d) deriving ethnicity-sensitive image features from the image filter groups based on contributions of the groups to a task of recognizing a given ethnic class against other ethnic classes, e) constructing probabilistic graphical models for recognizing the ethnicity of people using the ethnicity-sensitive image features as observable quantities of the probabilistic graphical models, f) training the probabilistic graphical models using the ethnicity-annotated facial images so that each of the probabilistic graphical models is dedicated to represent one ethnic class, g) extracting the ethnicity-sensitive image features of an input face, and h) determining the ethnic class of the input face based on the outputs computed from the probabilistic graphical models using the ethnicity-sensitive image features, wherein the ethnicity-sensitive image features are extracted based on specific locations from the facial images, and wherein the contribution of the grouping is computed based on comparison between the first joint histograms of the image filter responses conditioned on the given ethnic class and the second joint histograms of the image filter responses conditioned on other ethnic classes.