1. A component presence/absence judging apparatus for judging whether or not components are mounted at predetermined places on a board after component mounting operations which mount the components on the board, the apparatus comprising: an image pickup device for relatively moving the board and a camera to pickup images of the predetermined places on the board; ante-mounting feature acquisition means for acquiring at least brightness information as ante-mounting features from an ante-mounting image which the image pickup device picks up at each of the predetermined places on an ante-mounting board before mounting the components at the predetermined places thereon; post-mounting feature acquisition means for acquiring at least brightness information as post-mounting features from a post-mounting image which the image pickup device picks up at each of the predetermined places on a post-mounting board after mounting the components at the predetermined places thereon; classifier configuration means for configuring a classifier by registering the ante-mounting features and the post-mounting features in a support vector machine; post-mounting operation feature acquisition means for acquiring at least brightness information as post-mounting operation features from a post-mounting operation image which the image pickup device picks up at each of the predetermined places on an inspection board after mounting the components at the predetermined places thereon; input means for inputting the post-mounting operation features to the support vector machine configured as the classifier; and judgment means for judging whether or not a component is mounted at each of the predetermined places on the inspection board, by the support vector machine configured as the classifier.