- I received my Ph.D. in topological semigroups from the University of Georgia in 1963. I am a 5th generation Moore st... moreI received my Ph.D. in topological semigroups from the University of Georgia in 1963. I am a 5th generation Moore student [R. L. Moore, Gordon Whyburn, Alexander Donaphin Wallace, Robert Koch, Robert P. Hunter, John Selden]. I have taught at various universities in the U.S., Canada, Turkey, and Nigeria, and have directed 9 Ph.D.'s in mathematics. I served as Dean of Science, Bayero University in Nigeria, and upon returning to the U.S., took up research in undergraduate mathematics education. I was a member of the AMS/MAA Joint Committee on Research in Undergraduate Mathematics Education (CRUME) and various other MAA Committees. I was a Visiting Scholar at Peabody College; Vanderbilt, at the Division of Education in Mathematics, Science, and Technology, University of California at Berkeley; at the Center for Research in Mathematics and Science Education, San Diego State University; and the Department of Mathematics, Arizona State University. I am currently Adjunct Professor of Mathematics, New Mexico State University.edit
This paper is based on my Topic Session presentation to the Canadian Mathematics Education Study Group in Montreal in June 2017.
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This paper presents a theoretical perspective for understanding and teaching university students' proof construction. It includes features of proof texts with which students may be unfamiliar. It considers psychological aspects of proving... more
This paper presents a theoretical perspective for understanding and teaching university students' proof construction. It includes features of proof texts with which students may be unfamiliar. It considers psychological aspects of proving such as behavioral schemas, automaticity, working memory, consciousness, cognitive feelings, and local memory. We discuss proving actions, such as the construction of proof frameworks that could be automated, thereby reducing the burden on working memory and enabling university students to devote more resources to the truly hard parts of proofs.
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This theoretical paper suggests a perspective for understanding university students’ proof construction based on the ideas of conceptual and procedural knowledge, explicit and implicit learning, behavioral schemas, automaticity, working... more
This theoretical paper suggests a perspective for understanding university students’ proof construction based on the ideas of conceptual and procedural knowledge, explicit and implicit learning, behavioral schemas, automaticity, working memory, consciousness, and System 1 and System 2 cognition. In particular, we will discuss proving actions, such as the construction of proof frameworks, that could be automated, thereby reducing the burden on working memory and enabling university students to devote more resources to the truly hard parts of proofs.
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This paper reports the observed behaviors and difficulties that eleven precalculus and calculus students exhibited in reading new passages from their mathematics textbooks. To gauge the effectiveness of these students' reading, we... more
This paper reports the observed behaviors and difficulties that eleven precalculus and calculus students exhibited in reading new passages from their mathematics textbooks. To gauge the effectiveness of these students' reading, we asked them to attempt straightforward mathematical tasks, based directly on what they had just read. These students had high ACT mathematics and high ACT reading comprehension test scores and used many of the helpful metacognitive strategies developed in reading comprehension research. However, they were not effective readers of their mathematics textbooks. In discussing this, we draw on the psychology literature to suggest that cognitive gaps, that is, periods of lapsed or diminished focus, during reading may explain some of the ineffectiveness of the students' reading. Finally, we suggest some implications for teaching and pose questions for future research.
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This is the abstract for a largely theoretical paper in which we planned to discuss how one kind of affect, specifically feelings of rightness, appropriateness, caution, etc., can both arise from and contribute to reasoning " moves... more
This is the abstract for a largely theoretical paper in which we planned to discuss how one kind of affect, specifically feelings of rightness, appropriateness, caution, etc., can both arise from and contribute to reasoning " moves " in the process of proving theorems. This will be illustrated by the cases of Katherine, a graduate student, and Edward, an advanced undergraduate student. But first we will describe a design experiment, from which the data arose, and discuss the nature of feelings. The course The design experiment consisted of a modified R. L. Moore method course for beginning graduate and advanced undergraduate students, the purpose of which was to improve proving ability. Video recordings and field notes were made and a theoretical framework started to emerge, only two ideas of which will be useful here. First, proofs have a problem-oriented part in which conceptual understanding is used to solve a problem and a formal-rhetorical part that can be based only ...
In this paper, we describe preliminary results arising from the development of a modified R. L. Moore Method course devoted entirely to helping advanced university mathematics students improve their proving abilities. The paper describes... more
In this paper, we describe preliminary results arising from the development of a modified R. L. Moore Method course devoted entirely to helping advanced university mathematics students improve their proving abilities. The paper describes the course and why it might be needed. We also discuss kinds and aspects of proofs in a way that may be useful in gauging student progress, and in particular, introduce the idea of the formal-rhetorical and problem-centered parts of a proof. We go on to propose a theoretical perspective suggesting that much of proving depends on procedural knowledge in the form of small habits of mind, or behavioral schemas, and give three examples. This paper reports on results arising from an ongoing design experiment. The purpose of the experiment is to examine ways advanced undergraduate and beginning graduate mathematics students construct, and learn to construct, proofs and to design a course to facilitate that learning. The paper has a research orientation, b...
In this largely theoretical paper, we discuss the relation between a kind of affect, behavioral schemas, and aspects of the proving process. We begin with affect as described in the mathematics education literature, but soon narrow our... more
In this largely theoretical paper, we discuss the relation between a kind of affect, behavioral schemas, and aspects of the proving process. We begin with affect as described in the mathematics education literature, but soon narrow our focus to a particular kind of affect – nonemotional cognitive feelings. We then mention the position of feelings in consciousness because that bears on the kind of data about feelings that students can be expected to be able to express. Next we introduce the idea of behavioral schemas as enduring mental structures that link situations to actions, in short, habits of mind, that appear to drive many mental actions in the proving process. This leads to a discussion of the way feelings can both help cause mental actions and also arise from them. Then we briefly describe a design experiment – a course intended to help advanced undergraduate and beginning graduate students to improve their proving abilities. Finally, drawing on data from the course, along with several interviews, we illustrate how these perspectives on affect and on behavioral schemas appear to explain, and are consistent with, our students’ actions.
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In most mathematics courses students learn the subject matter of the course and also improve their skill at reasoning. Usually the subject matter is emphasized with the improvement in reasoning ability occurring in a natural but unplanned... more
In most mathematics courses students learn the subject matter of the course and also improve their skill at reasoning. Usually the subject matter is emphasized with the improvement in reasoning ability occurring in a natural but unplanned way. In this paper we give a brief description of a course in which we have reversed the traditional emphasis, placing more stress on improvement of reasoning ability. We then give a classification of student reasoning errors with examples. The purpose of this classification, and indeed of the course described here, is to find a way to remove these errors as early and efficiently as possible thereby accelerating students' development.
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This article sets the stage for the following 3 articles. It opens with a brief history of attempts to characterize advanced mathematical thinking, beginning with the deliberations of the Advanced Mathematical Thinking Working Group of... more
This article sets the stage for the following 3 articles. It opens with a brief history of attempts to characterize advanced mathematical thinking, beginning with the deliberations of the Advanced Mathematical Thinking Working Group of the International Group for the ...
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ABSTRACT
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This dissertation consists of an Introduction; Chapter 1 titled "Rings, Groups, Semigroups"; Chapter 2 titled "Semirings"; Chapter 3 titled "Gamma-Compact Semirings", and a Bibliography.
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A clan is a compact connected semigroup with unit. We show the question "Which clans are groups?" has a purely topological answer.
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Introduction. Suppose that 5 is a topological semigroup which contains the bicyclic semigroup B as a subsemigroup. Let T denote the closure of B in 5. We investigate the structure of the semigroup T and the extent to which B determines... more
Introduction. Suppose that 5 is a topological semigroup which contains the bicyclic semigroup B as a subsemigroup. Let T denote the closure of B in 5. We investigate the structure of the semigroup T and the extent to which B determines this structure. In §1, two properties of F are established which hold for arbitrary 5; namely, that B is a discrete open subspace of F and T\B is an ideal of T if it is nonvoid. In §11, we introduce the notion of a topological inverse semigroup and establish several properties of such objects. Some questions are posed. In §111, it is shown that if 5 is a topological inverse semigroup, then T\B is a group with a dense cyclic subgroup. §IV contains a description of three examples of a topological semigroup which contains B as a dense proper subsemigroup. Finally, in §V, we assume that 5 is a locally compact topological inverse semigroup and show that either B is closed in 5 or F is isomorphic with the last of the examples described in §IV. A corollary about homomorphisms from B into a locally compact topo-logical inverse semigroup is obtained which generalizes a result due to A. Weil [1, p. 96] concerning homomorphisms from the integers into a locally compact group. All spaces are topological Hausdorff in this paper.
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A topological semiring is a Hausdorff space S together with two continuous associative operations on S such that one (called multiplication) distributes across the other (called addition). That is, x(y+z) =xy+xz and (x+y)z = xz+yz for all... more
A topological semiring is a Hausdorff space S together with two continuous associative operations on S such that one (called multiplication) distributes across the other (called addition). That is, x(y+z) =xy+xz and (x+y)z = xz+yz for all x, y, and z in s . Note that, in contrast to the purely algebraic situation [l], [2], we do not postulate the existence of an additive identity which is a multiplicative zero. In this note we characterize compact additively commutative semirings which are multiplicatively left zero simple. This is accomplished by first examining semirings which are multiplicatively groups with zero and then proceeding to the general situation. For other remarks on compact semirings the reader is referred to [3], [4]. The notation follows closely that of topological semigroups [5].
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By a topological semiring we mean a Hausdorff space S together with two continuous associative operations on S such that one (called multiplication) distributes across the other (called addition). That is, we insist that x(y + z) = xy +... more
By a topological semiring we mean a Hausdorff space S together with two
continuous associative operations on S such that one (called multiplication) distributes across the other (called addition). That is, we insist that
x(y + z) = xy + xz and (x + y) z = xz + yz for all x,y and z in S. Note that, in contrast to the purely algebraic situation [1,2], we do not postulate the existence of an additive identity which is a multiplicative zero.
In this note we point out conditions under which the existence of such an
element is equivalent to the double simplicity of the semiring. We also discuss
maximal and minimal double ideals together with several examples.
continuous associative operations on S such that one (called multiplication) distributes across the other (called addition). That is, we insist that
x(y + z) = xy + xz and (x + y) z = xz + yz for all x,y and z in S. Note that, in contrast to the purely algebraic situation [1,2], we do not postulate the existence of an additive identity which is a multiplicative zero.
In this note we point out conditions under which the existence of such an
element is equivalent to the double simplicity of the semiring. We also discuss
maximal and minimal double ideals together with several examples.
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By a topological semiring we mean a Hausdorff space S together with two continuous associative operations on S such that one (called multiplication) distributes across the other (called addition). That is, we insist that x(y+z)=xy+xz and... more
By a topological semiring we mean a Hausdorff space S together
with two continuous associative operations on S such that one (called
multiplication) distributes across the other (called addition). That
is, we insist that x(y+z)=xy+xz and (x+y)z = xz+yz for all x, y,
and z in S. Note that, in contrast to the purely algebraic situation,
we do not postulate the existence of an additive identity which is a
multiplicative zero.
In this note we point out a rather weak multiplicative condition
under which each additive subgroup of a compact semiring is totally
disconnected. We also give several corollaries and examples.
with two continuous associative operations on S such that one (called
multiplication) distributes across the other (called addition). That
is, we insist that x(y+z)=xy+xz and (x+y)z = xz+yz for all x, y,
and z in S. Note that, in contrast to the purely algebraic situation,
we do not postulate the existence of an additive identity which is a
multiplicative zero.
In this note we point out a rather weak multiplicative condition
under which each additive subgroup of a compact semiring is totally
disconnected. We also give several corollaries and examples.
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A topological semiring is a Hausdorff space S together with two continuous associative operations on S such that one (called multiplication) distributes across the other (called addition). That is,x(y+z) =xy+xz and (x+y)z = xz+yz for all... more
A topological semiring is a Hausdorff space S together with two continuous associative operations on S such that one (called multiplication) distributes across the other (called addition). That is,x(y+z) =xy+xz and (x+y)z = xz+yz for all x, y, and z in S. Note that, in contrast to the purely algebraic situation [l], [2], we do not
postulate the existence of an additive identity which is a multiplicative
zero.
In this note we characterize compact additively commutative semirings which are multiplicatively left zero simple. This is accomplished by first examining semirings which are multiplicatively groups with zero and then proceeding to the general situation. For other remarks on compact semirings the reader is referred to [3], [4].
The notation follows closely that of topological semigroups [5].
postulate the existence of an additive identity which is a multiplicative
zero.
In this note we characterize compact additively commutative semirings which are multiplicatively left zero simple. This is accomplished by first examining semirings which are multiplicatively groups with zero and then proceeding to the general situation. For other remarks on compact semirings the reader is referred to [3], [4].
The notation follows closely that of topological semigroups [5].
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We answer the question, "Which clans are groups?"
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This is the second in a projected series of three papers, the aim of which is the complete description of the closure of any one-parameter inverse semigroupin a locally compact topological inverse semigroup. In it we characterize all... more
This is the second in a projected series of three papers, the aim of which is the complete description of the closure of any one-parameter inverse semigroupin a locally compact topological inverse semigroup. In it we characterize all one-parameter inverse semigroups. In order to accomplish this, we construct the free
one-parameter inverse semigroups and then describe their congruences.
one-parameter inverse semigroups and then describe their congruences.
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This submission for ICME-11, Topic Study Group 18 on reasoning, proof, and proving, concerns both the teaching of and the cognitive aspects of reasoning, proof, and proving (RPP). We have two aims. First, we aim to describe a new and... more
This submission for ICME-11, Topic Study Group 18 on reasoning, proof, and proving, concerns both the teaching of and the cognitive aspects of reasoning, proof, and proving (RPP). We have two aims. First, we aim to describe a new and unusual mathematics course for graduate and advanced undergraduate students. The entire purpose of this course is to help students improve their proving ability. This contrasts with other graduate and upper division university courses, whose purpose is normally mostly to inform students about some mathematical topic, such as real analysis or abstract algebra. Second, treating the development of the course as a design experiment, we aim to report on a theoretical framework emerging from the data and several other preliminary findings. In the following synopsis, we omit numerous references, examples, and excerpts of transcripts which would be included in a longer submission.
In this largely theoretical paper we discuss how one kind of affect, specifically feelings of rightness, appropriateness, caution, etc., can both arise from and contribute to reasoning “moves” in the process of proving theorems. This will... more
In this largely theoretical paper we discuss how one kind of affect, specifically feelings of rightness, appropriateness, caution, etc., can both arise from and contribute to reasoning “moves” in the process of proving theorems. This will be illustrated by the cases of Katherine, a graduate student, and Edward, an advanced undergraduate student. But first we will describe a design experiment, from which the data arose, and discuss the nature of feelings.
This Powerpoint presentation discusses university students’ mathematical and non-mathematical proving difficulties. A total of over forty proving difficulties have been observed and organized into nine categories. Of these difficulties,... more
This Powerpoint presentation discusses university students’ mathematical and non-mathematical proving difficulties. A total of over forty proving difficulties have been observed and organized into nine categories. Of these difficulties, more than twenty will be described. These observations come from several years of teaching an experimental proving course to beginning graduate and advanced undergraduate mathematics students and from teaching an experimental voluntary proving supplement to an undergraduate real analysis course. We believe that discussing and categorizing these difficulties will lead to a greater understanding of students’ thinking with regard to proof and potentially to better teaching.
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Persistence is important to successful non-routine problem solving and proving. It allows one to continue despite making arguments in seemingly unhelpful directions until one ultimately makes progress and comes to a successful result.... more
Persistence is important to successful non-routine problem solving and proving. It allows one to continue despite making arguments in seemingly unhelpful directions until one ultimately makes progress and comes to a successful result. Persistence is supported by a self-efficacy belief, which is“a person’s belief in his or her ability to succeed in a particular situation” (Bandura, 1995). We present three observations spanning university level mathematics from beginning undergraduates solving just explained, straightforward exercises, to actions needed in proof construction in mid-level U.S. university transition-to-proof courses, to the actual proof construction processes of mathematicians.
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We analyzed undergraduate students’ examination papers from a transition-to-proof course. We have identified process, rather than mathematical content, difficulties such as not constructing a proof framework first, not unpacking the... more
We analyzed undergraduate students’ examination papers from a transition-to-proof course. We have identified process, rather than mathematical content, difficulties such as not constructing a proof framework first, not unpacking the conclusion, and not using definitions correctly. Examples of these difficulties were presented.
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We report the results of a study of the proof validation abilities and behaviors of sixteen undergraduates after taking an inquiry-based transition-to-proof course. Students were interviewed individually towards the end of the course... more
We report the results of a study of the proof validation abilities and behaviors of sixteen undergraduates after taking an inquiry-based transition-to-proof course. Students were interviewed individually towards the end of the course using the same protocol that we had used earlier at the beginning of a similar course (Selden and Selden, 2003). Results include a description of the students’ observed validation behaviors, a description of their proffered evaluative comments, and the, perhaps counterintuitive, suggestion that taking an inquiry-based transition-to-proof course does not seem to enhance students’ validation abilities. We also discuss distinctions between proof validation, proof comprehension, proof construction and proof evaluation and the need for research on their interrelation.
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This presentation reports on the relationship between the logic taught and the logic used in students' proofs in one transition-to-proof course. In the U.S.A, such courses are often taken by second year mathematics majors and preservice... more
This presentation reports on the relationship between the logic taught and the logic used in students' proofs in one transition-to-proof course. In the U.S.A, such courses are often taken by second year mathematics majors and preservice secondary teachers. The focus is on teaching students to construct proofs of theorems. Typically logic is presented early in a somewhat abstract, decontextualized way and the students' experiences with theorem proving come later.
We think having a description of the structure of already written proofs might be useful in analyzing students' attempts to read proofs or construct their own proofs. We consider what we call a hierarchical structure based on... more
We think having a description of the structure of already written proofs might be useful in analyzing students' attempts to read proofs or construct their own proofs.
We consider what we call a hierarchical structure based on subproofs, subconstructions, and parallel arguments (such as case arguments). This is an extension of our proof framework idea and is illustrated by a proof of the theorem: is continuous at a point provided and are, which appears below in the Appendix A.
We consider what we call a hierarchical structure based on subproofs, subconstructions, and parallel arguments (such as case arguments). This is an extension of our proof framework idea and is illustrated by a proof of the theorem: is continuous at a point provided and are, which appears below in the Appendix A.
