Full Paper Program
The following full papers have been accepted for presentation at the Diagrams 2006 conference.
Perceiving Relationships: A Physiological Examination of The Perception of Scatterplots
Researchers in all areas of science recognize the value of graphical
displays and much of the research on graphs has focused on determining
which graphical elements enhance the readability of a display. To
date, there has been no research examining the physiological
processing of graphs. The purpose of this project was to examine the
event-related potentials (ERPs) associated with the processing of
bivariate scatterplots. Participants viewed scatterplots depicting
different types of linear relationships (positive and negative; strong
and weak) and their ERPs were analyzed. Results indicate interesting
differences in how scatterplots are processed by the brain. Overall,
there was differential processing in posterior, medial, and anterior
brain sites. Sites on the left and right sides of the brain showed
different patterns of activity in response to the scatterplots
depicting the various relationships. In addition, these results
suggest that different types of relationships are processed
differently in the brain (confirming previous research that has
suggested that the perception of covariation is dependent upon the
type of relationship depicted on a scatterplot).
Notational Variety in Boundary Logic
Boundary logic is a formal diagrammatic system that combines Peirce's
Entitative Graphs with Spencer Brown's Laws of Form. Its conceptual
basis includes boundary forms composed of non-intersecting closed
curves, void-substitution (i.e. deletion) as the primary proof
procedure, and semipermeable boundaries that define valid
transformations. Boundary logic is first briefly described, and then
several new diagrammatic notations for logic derived from geometrical
and topological transformation of boundary forms are presented. The
calculus and an example proof of modus ponens is provided for textual,
enclosure, graph, map, path and block based forms. These new
diagrammatic languages for logic convert connectives into
configurations of containment, connectivity, contact, conveyance, and
concreteness.
Diagrams as Physical Models
The dominant account of the role of diagrams in reasoning, as
exemplified by the work of Barwise and associates, is that they are
"sentences" in a 2-D language, with specialized rules of inference
that generate new diagrams. We discuss a larger variety of roles for
diagrams in helping with reasoning, focusing in particular on their
role as physical models of states of affairs, much like an
architectural model of a building or a 3-D molecular model of a
chemical compound. We discuss the concept of a physical model for a
logical sentence, and the role played by the causal structure of the
physical medium in making the given sentence as well as a set of
implied sentences true. When the physical model is prototypical, it
supports the inference of certain other sentences for which it
provides a model as well. We also informally discuss a proposal that
diagrams and similar physical models help to explicate a certain sense
of relevance in inference, an intuition that so-called Relevance
Logics attempt to capture.
Communicative Signals as the Key to Automated Understanding of Bar Charts
This paper discusses the types of communicative signals that
frequently appear in bar charts and how we exploit them as evidence in
our system for inferring the intended message of an information
graphic. Through a series of examples, we demonstrate the impact that
various types of communicative signals, namely salience, captions and
estimated perceptual task effort, have on the intended message
inferred by our implemented system.
Evaluation of ERST - an External Representation Selection Tutor
This paper describes the evaluation of ERST, an adaptive system which
is designed to improve its users' external representation (ER)
selection accuracy on a range of database query tasks. The design of
the system was informed by the results of experimental studies. Those
studies examined the interactions between the participants' background
knowledge-of-external representations, their preferences for selecting
particular information display forms, and their performance across a
range of tasks involving database queries. The paper describes how
ERST's adaptation is based on predicting users' ER-to-task matching
skills and performance at reasoning with ERs, via a Bayesian user
model. The model drives ERST's adaptive interventions in two ways - by
1. hinting to the user that particular representations be used, and/or
2. by removing from the user the opportunity to select display forms
which have been associated with prior poor performance for that
user. The results show that ERST does improve an individual's ER
reasoning performance. The system is able to successfully predict
users' ER-to-task matching skills and their ER reasoning performance
via its Bayesian user model.
Topological Relations of Arrow Symbols in Complex Diagrams
Illustrating a dynamic process with an arrow-containing diagram is a
widespread convention in people's daily communications. In order to
build a basis for capturing the structure and semantics of such
arrow-containing diagrams, this paper formalizes the topological
relations between two arrow symbols in such a diagram and discusses
the influence of topological relations on the diagram's
semantics. Topological relations of arrow symbols are established by
two types of links, intersections and common references, which are
further distinguished into nine types based on the combination of the
linked parts of two arrow symbols. The topological relations are
captured by the existence/non-existence of these nine types of
intersections and common references. Then, this paper demonstrates
that arrow symbols with different types of intersections illustrate
two actions with different interrelations, whereas those with common
references illustrate a pair of semantics that may be mutually
exclusive or synchronized.
Flow Diagrams: Rise and Fall of the First Software Engineering Notation
Drawings of water are the earliest, least abstract forms of flow
diagram. Representations of ideal or generalised sequences for
manufacturing or actual paths for materials between machines came
next. Subsequently documentation of production and information flow
become subjects for graphical representation. A similar level of
abstraction was necessary for representations of invisible flows such
as electricity. After initial use to define control, flow diagrams
became a general purpose tool for planning automated computation at
all levels of composition. Proliferation of syntax variants and the
need for a common language for documentation were the motivations
behind standardisation efforts. Public communication of metalevel
systems information superseded private comprehension of detailed
algorithmic processes as a primary function. Changes to programming
language structures and their associated processes caused the initial
demise of flow diagrams in software engineering.
On Line Elaboration of a Mental Model During the Understanding of an
Interactive Animated Mechanical System: Eye Tracking and Comprehension
This experiment examines how learners integrate and understand an
animation about a mechanical complex three pulleys system (Hegarty &
Just, 1993; Hegarty, 2004). We tested two populations of learners,
with high mechanical and spatial abilities and with low spatial and
mechanical abilities. For all subjects, their task consisted to
understand an animated three pulleys system. Two variables were
manipulated: the controllability of the animations and the orientation
of the attention of the learners. During the inspection of the
animation by the subjects, we recorded their eye tracking to carry on
line information about dynamic cognitive processing. After the
inspection of the animation, the subjects answered to a comprehension
test about the pulleys system. We distinguished three different levels
of integration of the system: configuration, local kinematics and
entire functional model. The comprehension test results indicated a
positive effect of a full controllable animation and also a positive
effect of a specific orientation of attention, on the functional model
and on local kinematics. The eye tracking data indicated that the
learners process highly the areas of the animations where a great
amount of motion is involved along the causal chain of events. We show
an effect of the controllability of the system and of a specific
orientation of attention of the learner on the amount of eye fixations
and on the number of transitions between areas that included the
causal chain. With a specific orientation of their attention on the
kinematics and on the entire functional model, learners watched less
the irrelevant areas of the animated diagram for the integration of
the causal chain.
Exploring the Notion of Clutter in Euler Diagrams
Euler diagrams are an effective and intuitive way of representing
relationships between sets. As the number of sets represented grows,
Euler diagrams can become cluttered and lose some of their intuitive
appeal. In this paper we consider various measures of clutter for
abstract Euler diagrams and compare these metrics with results
obtained from an empirical study. We also show that all abstract Euler
diagrams can be constructed inductively by inserting a contour at a
time and we relate this inductive description to the clutter metrics.
Finally, we consider how our notions of clutter relate to concrete
nesting of Euler diagrams.
Toward a Comprehensive Model of Graph Comprehension: Making the Case
for Spatial Cognition
We argue that a comprehensive model of graph comprehension must
include spatial cognition. We propose that current models of graph
comprehension have not needed to incorporate spatial processes,
because most of the task/graph combinations used in the psychology
laboratory are very simple and can be addressed using perceptual
processes. However, data from our own research in complex domains that
use complex graphs shows extensive use of spatial processing. We
propose an extension to current models of graph comprehension in which
spatial processing occurs a) when information is not explicitly
represented in the graph and b) when simple perceptual processes are
inadequate to extract that implicit information. We apply this model
extension to some previously published research on graph comprehension
from different labs, and find that it is able to account for the
results.
Active Comparison as a Means of Promoting the Development of Abstract Conditional Knowledge and Appropriate Choice of Diagrams in Math Word Problem Solving
Although the ability to select an appropriate diagram to suit the task
at hand is one important aspect of graphic literacy, novices have been
shown to have a problem with this. To examine how it might be possible
to bridge the gap between experts and novices that has been identified
in previous research, the present study investigated whether teaching
sessions involving active comparison of diagrams and review of lessons
leant from problem solving sessions would facilitate the development
of participants’ abstract conditional knowledge and use of appropriate
diagrams in subsequent problem solving. Fifty-eight 8th grade
participants were assigned one of the two conditions and were provided
with instruction and assessment sessions over five days. In both
experimental and control conditions, traditional math classes were
provided in which diagrams were used in explaining how to solve
various math word problems. However, the experimental group was
additionally provided with sessions to actively compare diagrams used
and review lessons learnt from problem solving. The results of
subsequent assessments showed that participants in the experimental
condition constructed more appropriate diagrams in solving math word
problems. In an assessment of conditional knowledge, these
participants also provided more abstract and detailed descriptions
about the uses of diagrams in problem solving. Implications for
diagrams research and student math instruction are discussed.
From Shape to Structure by Analogical Transfer
We propose a case-based method for constructing a structural model of
a schematic diagram of a physical system through analogical mapping
and transfer. A source case may contain (1) a 2-D vector-graphics line
drawing of a physical device, (2) a specification of the shapes and
spatial relations in the drawing, and (3) a specification of the
components and connections of the device depicted in this
diagram. Given an input of a target 2-D vector graphics line drawing
and a description of the shapes and spatial relations in it, we ask
how an agent might align the two drawings and transfer the relevant
structural elements over to the new drawing, giving as output a
specification of the components and connections depicted in the input
drawing. The domain is engineering design of kinematic devices that
convert translational motion into rotational motion, such as a piston
and crankshaft device. The Archytas system implements this method for
situations in which the drawings in the source case and the target
problem are very similar.
Exploring the Effect of Animation and Progressive Revealing on Diagrammatic Problem Solving
We conducted eye-tracking studies of subjects solving the problem of
finding shortest paths in a graph using a known procedure (Dijkstra’s
algorithm). The goal of these studies was to investigate how people
reason about and solve graphically presented problems. First, we
compared performance when the graphical display was animated to when
the display was static. Second, we compared performance when the
display was initially sparse, with detailed information being
progressively revealed, to when the display presented all information
simultaneously. Results suggest that while animation of the procedure
or algorithm does not improve accuracy, animation coupled with
progressively revealing objects of interest on the display does
improve accuracy and other process measures of problem solving.