Logic software for apprenticeship in rough reasoning. In

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Logic Software for Apprenticeship in Rough
Reasoning
Bertil Rolf
Blekinge Institute of Technology, School of Management
SE-372 25 Ronneby, Sweden
bertil.rolf@bth.se
Abstract
The Athena logic software packages are designed to improve on the
teaching of rough reasoning procedures. Often, human actors, experts and
decision makers have access only to low quality data and fallible
indicators, guiding their judgment. In such situations, rough reasoning
procedures will achieve better results than more elaborate reasoning
procedures. Athena supports the development of rough reasoning skills via
an apprenticeship method. Teaching of rough reasoning procedures can
benefit from software supported apprenticeship method, integrating
software use with educational games.
Part I: Introduction
Logic can be seen as an art of reasoning or a science of reasoning. I am here
interested in arts or skills of reasoning. Arts of reasoning are forms of procedural
knowledge, i.e. the mastery of arts of reasoning consists in the proper execution of
the proper procedures of reasoning. Such procedures can be made the educational
objective of teaching.
The aims of this paper are (1) to present an integrated, software-based system of
cognitive apprenticeship learning of reasoning skills. (2) To explain why such a
system might be educationally effective. (3) To epistemically justify the reasoning
procedures taught in “rough” domains.
Part II: The Athena Apprenticeship Approach
The Athena approach is a way of using logic software to support reasoning
apprenticeships. We assume that reasoning skills surface and give an advantage in
a peculiar type of situations. Typical of such situations is that (a) several parties
possess the same data or premises but (b) the parties reach different conclusions
and (c) their different conclusions rest on their different procedures for using
premises to support their respective conclusion and (d) it is possible to evaluate
some of these procedures as better or worse. The participants will partly agree,
partly disagree about premises and conclusions. We have constructed a number of
such type situations [Rol02]:
 Seminar: Two teams are given roles as opponent and respondent to a scientific
paper, chosen by the teachers. The learning objective is to apply criteria of
research quality.
 Panel debate: Two teams are assigned tasks as expert committees, one arguing
pro the sustainability of the European Agricultural Policy, one contra. The
learning objective is to understand the pros and cons of the E-CAP.
 Internal business decision-making: A firm is approached by a problematic
customer. Should the customer be accepted or not? Teams argue pro et contra
in a company setting. The learning objective is ability to mobilize, organize
and communicate economic knowledge in a professional role.
 Business-business negotiation: Two teams are assigned roles as buyers and
sellers, respectively of a software solution. The learning objective is to analyze
preferences of self and opponents and managing negotiations towards an
efficient frontier.
 City planners-business negotiation: Two teams represent a commercial
developer and city planners, respectively. The learning objective is to analyze
preferences of self and opponents and managing negotiations towards an
efficient frontier.
A glance at the learning objectives will show that reasoning skills are integrated
into a wider set of professional skills, including skills of communication and
social skills.
This kind of courses has been given at all levels in undergraduate and
postgraduate education. Instruction dominates teaching of undergraduates while
common argument construction or interpretation dominates graduate teaching. In
negotiations, outcome feedback on negotiated solutions can be given
instantaneously, comparing teams at a class level.
Student’s tasks progress towards complexity where simpler tasks are similar to the
more complex. To the student, the progression in a four-week course starts by the
assignment to a team. The task can be to present and defend in two weeks time a
coherent stance Pro a standpoint against an opposing Con-team. One week later,
the Pro-team and Con-team will switch sides.
Instructions and subtasks are mainly conducted in one of our two software
packages, Athena Standard or Athena Negotiator. A first day is spent on lectures
and exercises analyzing or constructing arguments in the software. Feedback is
given. In a second step, student teams are to build a template, representing the
kinds of arguments that can be adduced in a matter. Finally, the students
accommodate their templates to the standpoint to be defended. Grading and
feedback is based on templates and final standpoint.
Part III: The Software Packages in Education
The role of the software is to facilitate the student’s grasp of the target procedures
of education, to facilitate teamwork and communication between teachers and
students. The reasoning procedures in preparing for oral argumentation are steered
through a procedure, largely representable through graphs in the software.
Fig. 1. Athena Standard (left), showing tree graph with report viewer presenting text
output. Athena Negotiator (right), showing outcome diagram for two-party negotiation.
The idea of the tree diagrams in the Athena Standard software is to teach students
the hierarchical structure of argumentation in contrast to linear structures of
presentation. Athena Standard is one of half a dozen operational software
packages suitable for elementary argument analysis and argument production.
Roughly half of these packages – Athena, Belvedere and Reason!Able – have
been widely tested in real educational settings [Rol03], [Gel00]. All of them
contain tree graphs, based on the ideas of Arne Naess or Stephen Toulmin.
The role of this type of software package is to externalize procedures of logic and
to cast them in a standardized form. If all students in a computer laboratory work
on the same task, it is easy for a teacher to give them appropriate hints and
feedback. It is easy for the student groups to experiment with different
interpretations and constructions and to ask the teacher about their understanding
of procedures. Team cooperation and competition between teams in oral
argumentation contests help provide motivation.
Specific for Athena is that the nodes of the tree graph contain large amounts of
texts that can be entered by opening the node in the tree graph. By selecting a
specific output report type, the user can produce handouts, position statements,
full reports or comparisons of argument trees, as seen above. This facilitates
various types of handouts related to various educational contests games. These
games often start with presenting a position statement, supported by a handout or
a memorandum.
The role of the software in relation to the educational games is that the use of the
software gives the students a check as to whether they are well prepared. This is
accomplished by having students to build templates, which give a kind of
checklists or topoi indicating which points to look for in evaluating a research
article. The students hand in templates and specific preparations made for the
educational games in the form of *.ath-files that are graded by the teacher.
Athena Negotiator contains linear functions, producing a weighted average of the
weights and values of subcomponents. The underlying theory is that of
multicriteria decision analysis [Rai82], [Kee93]. Here, it is applied to two parties
in negotiations.
Part IV: Effectiveness of Apprenticeship
An “educationally effective” system is one that is likely to produce most of the
intended effects in users and few effects counter to intentions.
All educational effects of reasoning software interact with the way software enters
into teaching, student tasks and exams. We cannot, therefore, know about
educational effects of reasoning software per se but only about the effects of
educational systems of which software is a part [Rol05]. There is general evidence
that educational systems based on reasoning software are more effective than
systems without software [Gel00], [Hit].
Developing procedural knowledge can take two different approaches. One – the
“alphabetic” approach – decomposes complex procedural knowledge into basic
elements that can be combined into any complex procedure, roughly the way one
can teach reading skills by first teaching letters, then words, then sentences,
paragraphs, essays and books. Clearly, this kind of education is facilitated in wellaxiomatized areas where the basics and their relation to the complexes are
explicitly understood.
The second approach is apprenticeship models. They have been used for millennia
in developing job skills, integrated into the work structure. In an apprenticeship
approach, tasks presented to the learner contain most of the difficulties but in an
elementary form. Subtasks or initial tasks are similar to full tasks. By learning
subtasks and generalizing to full tasks on the basis of similarity, learners can be
expected to learn how to manage full tasks. Reasoning apprentices are given a
progression of more complex tasks similar to a tailor apprentice that starts by
sowing sleeves before proceeding to more complex tasks and finally full
garments.
Typical of apprenticeship learning is also a form of social embedding where
learners bear a social role, function or status. Tasks are not merely cognitively
demanding, but their solution also put demands on social enactment.
There are several characteristics of apprenticeship-guided courses. One can
construct simulated real life situations for developing and exercising reasoning
skills. One can use scaffolding techniques to promote collaboration within student
teams and between teacher and student teams.
The model of “cognitive apprenticeship” is developed to make the best of
apprenticeship learning within educational institutions [Col89]. It has been tested
in vocational training and professional education with positive results. Cognitive
research has shown that learners of complex tasks will benefit largely from
feedback directed towards user procedures, so-called “cognitive feedback”, rather
than feedback related to quality of outcome [Bre94].
The cognitive apprenticeship model can be seen as a normative device for
opening up target procedures and user procedures. The Athena software packages
provide a standardized means of representation for problem solving. Its
conceptual system facilitates easy discussion between students in the computer
lab. A teacher will be able to diagnose immediately and to comment on student
problem solving. Students can be given home assignment, analyzing complex
scientific arguments, and deliver their solutions as files to be discussed in a class,
using a computer with projector.
Part V: Justification of Rough Reasoning
There are limitations to argument-mapping software. The Athena-type software
incorporates inferential procedures that are defensible only in special cases, e.g.
when the probability of the premises is independent of one another. If inferences
can run in several directions, e.g. in a Bayesian network, logic mapping software
does not seem able to capture such reasoning well. Furthermore, if we have an
argument from the premise A to the conclusion C, the symbolism permits the
addition of an extra argument B pro/con A or C but not for or against the
conditional probability P(C/A). If B says: “A is not relevant to C”, there is no way
of symbolizing B. (Something of the same kind can be said for Toulmin’s
argument theory where criticism of backings cannot be represented.)
For these reasons, it may seem that argument-mapping software is unattractive
from a stance of logical theory, even if it is educationally feasible. However,
another type of epistemological justification can be given.
In philosophical epistemology, reliability theories of knowledge claim that
knowledge consists in such beliefs that reliably ”track” the fact they represent. In
the psychology of judgment, such theories have been studied empirically since the
1950’s. The success or failure of judgment can be studied within various versions
of the ”lens model” [Ham96].
The lens model assumes that we ascribe states to objects that go beyond what we
directly sense. A kind of correspondence theory of truth is assumed and by
”success” or ”accuracy”, we refer to the agreement of the judged state of the
object with its real state. Failure consists in non-correspondence. Any judgment
relies on a number of fallible indicators or cues. These cues contain more or less
information indicated by the ”ecological validity” of the cues themselves.
However, the cues are seldom optimally utilized by the subject but only more or
less so.
Some key results about expert judgment are relevant to argument-mapping
procedures. First, human expert judgment can seldom improve on linear
regression models of the cues underlying judgment where regression is used to
establish cue weights. Second, human experts often are inconsistent in their
reliance on cues. Third, in non-deterministic domains where feedback to experts is
delayed or absent, experts do not “learn from their experience”. Fourth, experts in
such domains tend to a radical overconfidence about the accuracy of their
judgment [Plo93].
Athena Standard and similar software packages involve a complication of the lens
model by introducing hierarchies of information cues. In the lens model itself,
only first order nodes, i.e. nodes of direct relevance to the conclusion, are used for
an assessment. But in an argument tree, there are also nodes of the second order,
third order and so on. Each node is assigned an acceptability value based on the
relevance and the acceptability of each subordinate node.
There are several reasons why we would expect hierarchical models to improve
on non-hierarchical lens model judgment. These reasons lie not in the increased
number of fine-grained cues. Instead, the software helps us select and structure
such cues. Procedures towards this end, I will refer to as procedures of “rough
reasoning”.
My case for rough reasoning procedures relies on the fact that the accuracy of
expert judgment often does not need full linear models combining weights and
values of cues. There are two different, known types of simplifications in relation
to full linear models.
One simplification, first discovered by Robyn Dawes in the 1970’s is that we can
use unit weights instead of regression based weights and still achieve a high
degree of accuracy in professional judgment. Often cues correlate with one
another. Unit weights are robust and generalize to new domains without the need
for unrealistically large, high quality data sets, such as those demanded by
regression methods [Daw88].
Another simplification is that of ”fast and frugal heuristics” in Gigerenzer’s
school [Gig99]. Surprisingly simple cues can generate judgments of higher
accuracy among laypersons than the accuracy of many an expert. Laypersons rely
on few cues, sometimes only a single cue (“Take the best”), which correlate
strongly with the state of the object. Experts try to employ several cues, each of
less ecological validity, which they fail to combine properly.
Both these applications of lens models show that accurate expert judgments can
be had from simple models. Many experts exercise reason in domains where
accessible data are bad; the collected data bear uncertain relations to the present
case; causal dependencies are weak; or combinations of cues offer intricate
complexity. In such cases, the maximal accuracy is low and cannot be improved
by more sophisticated weighing of larger number of cues [Buc03], [Rol06].
The relevance of Athena and argument mapping to simplifications of regression
lens models is as follows. First, the results of Dawes and Gigerenzer establish that
simple models will often suffice to reach good accuracy of judgment. But their
proposed models are different. In Dawes’ unit weight models, a possibly large
number of cues are given equal weight. In Gigerenzer’s ”Take the best” model, a
single cue is selected according to a lexical order. Clearly, there is a need to select
which model to use in order to improve on accuracy.
Second, the original lens model fits well for perceptual judgment. In perception,
there is often a natural limit to the cues presented. I perceive natural objects and
the validity of the cues are based on induction over natural kinds. But professional
inductive judgment is more problematic than perceptually based judgment. Say a
schoolteacher wants to predict the success of a 15 year-old student. There is a
myriad of facts available to the teacher. The facts have no obvious internal
structure. Some are biological, some social, some related to previous school work,
some related to the school class. Some cues are specific for the students, others
general. Cues that had predictive strength ten years ago need not be valid today.
The Athena Standard type of software can represent different lens models. Cues
can be selected, ordered, assessed and filtered. If we assign weights and values in
one way in Athena, a Dawesian unit weight model results. If we do it in another
way, one of Gigerenzer’s models results. Thus selected and sorted, the cues would
form a lens model with relevance weights and acceptability values assigned.
Hence, there are domains where the accuracy of expert judgments obtained by
rough reasoning cannot be improved. Although the most accurate lens model that
is reached after rough reasoning in Athena in such a domain is simple per se, the
rough reasoning procedures used to select the model may be complex, obscure or
counterintuitive. In such domains, rough reasoning procedures, supported by
Athena-type logic software will be the best general procedures that are humanly
possible.
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Acknowledgments. This work has been granted support from the Swedish Environmental
Protection Agency. A previous version has benefited from comments by C. C. Rolf.
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