The concept of grouping in relational algebra is well-known from its connection to aggregation. In this paper we generalize the grouping notion by defining a simultaneous grouping of more than one relation, and we discuss the application of operations on grouping elements other than just arithmetic aggregation. Finally we show that this grouping mechanism can be added to relational algebra with...

A model for perceptual grouping based on measurements of spatial correlations is proposed and tested. Gestalt-like grouping experiments were performed to study and quantify the effect of element similarity (shape, luminance) and proximity. Observers reported the horizontal or vertical organization of stimuli with proximity and similarity providing conflicting grouping cues. Proximity grouping w...

Keywords: Perceptual grouping Early human vision Image pixel grouping Local image structure Graph partitioning Normalized cut a b s t r a c t Graph partitioning for grouping of image pixels has been explored a lot, with normalized cut based graph partitioning being one of the popular ones. In order to have a credible allegiance to the perceptual grouping taking place in early human vision, we p...

Perceptual grouping has traditionally been thought to be governed by innate, universal principles. However, recent work has found differences in Japanese and English speakers' non-linguistic perceptual grouping, implicating language in non-linguistic perceptual processes (Iversen, Patel, & Ohgushi, 2008). Two experiments test Japanese- and English-learning infants of 5-6 and 7-8 months of age t...

The present study further investigates findings of impairment in Gestalt, but not global processing in ASD (Brosnan, Scott, Fox & Pye, 2004). Nineteen males with ASD and nineteen typically developing males matched by non-verbal ability, took part in five Gestalt perceptual grouping tasks. Results showed that performance differed according to grouping type. The ASD group showed typical performan...

In supervised machine learning, the partitioning of the values (also called grouping) of a categorical attribute aims at constructing a new synthetic attribute which keeps the information of the initial attribute and reduces the number of its values. In this paper, we propose a new grouping method MODL founded on a Bayesian approach. The method relies on a model space of grouping models and on ...

We address the challenges of how to model human perceptual grouping in random dot arrays and how perceptual grouping affects human number estimation in these arrays. We introduce a modeling approach relying on a modified k-means clustering algorithm to formally describe human observers' grouping behavior. We found that a default grouping window size of approximately 4° of visual angle describes...

Grouping is an essential process of computer vision. However, measurement of grouping results is not straightforward and is often heuristic. We propose here a method for measuring grouping quality which is based on the following observation: the grouping result provides some information about the true, unknown grouping and reduces its uncertainty. This uncertainty is evaluated by the number of ...

We propose a novel framework for perceptual grouping based on the idea of mixture models, called Bayesian hierarchical grouping (BHG). In BHG, we assume that the configuration of image elements is generated by a mixture of distinct objects, each of which generates image elements according to some generative assumptions. Grouping, in this framework, means estimating the number and the parameters...

Perceptual grouping is usually defined by principles that associate distinct elements by virtue of image properties such as proximity, similarity, and occurrence within common regions. What role does learning play in forming a perceptual group? This study provides evidence that learning of shape associations leads to perceptual grouping. Participants were repeatedly exposed to pairs of unique s...