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1
Assessing College Students’Retention and Transfer
from Calculus to Physics
Lili Cui
Physics Education Seminar
Monday, Feb 13, 2006
2
Transfer of Learning
Transfer is often defined as the ability to apply what has been learned in one
context to a new context 1
1 Byrnes (1996)
3
MotivationStudents need to apply what they have learned in one class to another class.
Students must be prepared to apply what they have learned in school to the real world.
Transfer = Problem solving
4
Various TransferStudent’s World
‘Real’World
School
Other Courses
Physics Courses
Other Physics Courses
One Course
Classroom
Exam
5
Research QuestionsTo what extent do students retain and transfer their calculus knowledge when solving problems in introductory physics?
What difficulties pertaining to the transfer of calculus do students have while solving these problems?
What strategies may help students overcome these difficulties?
6
WORKING MEMORY
READ-OUTFILTER
LONG TERM
MEMORY
Read-outProblem Info.
Priming
Information in a physics problem
What type of knowledge?Self-made ORFrom ‘authority.’
External Inputs
Asso
ciat
e
ActivatedPrior Knowledge
Activ
ate
PriorKnowledge
ActivatedEpistemic
Mode
Activ
ate
Epistemic Mode
Control
Control
Model of Transfer 2
Control
2 Rebello, Zollman, et. al. (2005)
7
Model of Transfer : Focusing inTransfer is the creation of associations between read-out information & prior knowledge
The association is controlled by other factors e.g. learners’epistemology, motivation etc.
Read-outInformation
PriorKnowledge
Association? Control
3 Redish (2004)
8
Two Kinds of Associations
Assigning the value of a problem variable to a knowledge element.
e.g. Line of charge extends from x=0 to x=5
Associations between two different knowledge elements.
e.g. Integral of Electric field is the Electric potential.
9
Theoretical Framework (1 of 3)
Two kinds of problem solving
‘Horizontal’Applying a pre-constructed schema to a problem.
Associations between read-out problem variables & elements of schema.
‘Vertical’Constructing a new schema to solve a problem.
Association between knowledge elements to create schema.
schema
Problem variables
New knowledge elements incorporated in schema, others
are discarded
A “schema” is a mental model for
solving a problem.
10
Theoretical Framework (2 of 3)
‘Horizontal’ Transfer
‘Vertical’Transfer
11
Theoretical Framework (3 of 3)
Focus on “Innovation”9Focus on “Efficiency”9
Choosing, using and constructing multiple internal representations6
Limited internal representations in different contexts6
Asses: ‘Prep. for Future Learning’7Asses: ‘Sequestered Prob. Solv.’7
Involves Inductive reasoning: ‘Model development’10
Involves deductive reasoning: ‘Model deployment’10
Uses “interpretive” knowledge8Uses “applicative” knowledge8
Ill-structured, non-traditional probs6Structured, traditional problems6
“High Road”4, “Class A”5 Transfer“Low Road”4, “Class C”5 Transfer
‘‘VerticalVertical’’ Problem SolvingProblem Solving‘‘HorizontalHorizontal’’ Problem SolvingProblem Solving
44 Salomon & Perkins (1989)Salomon & Perkins (1989) 55 diSessa & Wagner (2005)diSessa & Wagner (2005) 66 JonassenJonassen (2003)(2003)
77 Bransford & Schwartz (1999)Bransford & Schwartz (1999)
99 Schwartz, Bransford & Sears (2005)Schwartz, Bransford & Sears (2005) 1010 Hestenes (1987)Hestenes (1987)
88 Broudy (1977)Broudy (1977)
12
Research Questions – ReframedTo what extent do students retain and transfer their calculus knowledge while problem solvingproblem solving in introductory physics?
What difficulties pertaining to the transfer of calculus do students have while problem problem solvingsolving?
What strategies may help students overcome these difficulties?
Have students retained their calculus Have students retained their calculus schema to solve calculus problems?schema to solve calculus problems?
Can they associate their physics problem Can they associate their physics problem variables with their calculus schema? variables with their calculus schema?
Can students appropriately activate their Can students appropriately activate their calculus schemas in physics problems?calculus schemas in physics problems?
Can students deconstruct and Can students deconstruct and reconstruct their schemas to solve a reconstruct their schemas to solve a physics problem? physics problem?
PHASE I: PHASE I: ‘‘HorizontalHorizontal’’ TransferTransfer
PHASE II: PHASE II: ‘‘VerticalVertical’’ TransferTransfer
PHASE III:PHASE III:Instructional StrategiesInstructional Strategies
13
Research Plan
‘Horizontal’ Transfer
‘Vertical’ Transfer
Study I-1: Quantitative: Exam problems
Study I-2: Qualitative: Textbook-like problems
Study II-1: Qualitative: ‘Contrasting Cases’ 9
Study II-2: Qualitative: ‘Jeopardy’ Problems 11
Phase I
Phase II
9 Schwartz, Bransford & Sears (2005)
11 Van Heuvelen & Maloney (1999)
Phase IIIInstructor Interviews
14
Participants
Students2nd semester, calculus-based physics
Electricity and Magnetism
Faculty, Instructors and TAs Physics
Mathematics
15
Phase I: Study I-1 Quantitative Students’ Exam Performance
Calculus-based physics studentsN=147 for Fall 2004
N=269 for Spring 2005
Three exams were collected each semester
Develop individual rubric to measure physics correctand calculus correct in every calculus-based physics problem
Calculate the Pearson Correlation between students’calculus and physics performance
16
Example of Exam and According Rubric
17
SummaryPhase I: Study I-1
Statistically significant correlations between math and
physics performance
Possibility of ‘horizontalhorizontal’ transfer from calculus to physics
Interview to further examine‘horizontalhorizontal’’ transfer
18
Phase I: Study I-2 Qualitative Interview, Fall 2004
Participants8 students, volunteer, male,
Most second year in college
Major in ME
Two sessions
For each session:About one hour long
Solve two physics problems
Solve isomorphic calculus problems
General questions about calculus background and application of their calculus knowledge in physics
1) E field caused by a half-circle charge distribution
2) Electric potential caused by changing E field
3) B field caused by a non-constant current distribution
4) Induced current caused by moving of the loop in a changing magnetic field
19
Results : Study I-2 (1 of 2)
Self-confidence in calculus knowledge retention
Realization that calculus is required in physicsCorrelation Transfer
Is the knowledge learned in calculus class enough for physics class?
Yes (7 of 8)
No (1 of 8)
“have done it so many times…”“remember well…”,
“just easy integrals…”, “using it all the time…”
“Not hard…”, “have not come across many situations that I have no idea what the math means over there…”
“because it would teach you the basic mathematics, but at some point, I need
them to teach me the different aspects as what’s going on here (physics question)…
although I am satisfied with my math, I think it is not enough to help me with
physics…”
“Use a lot of calculus in physics, more than use physics in calculus”“The math is kind of foundation of physics, do not understand math, you can not do physics”“Physics talks why to solve it, math talks how to solve it. You apply the formula to physics”
20
Lack of confidence in setting-up physics problems
Added question: Without calculus knowledge, it is possible to set up the physics problem?
Yes (2 of 5)
Do not know (1 of 5)
No (2 of 5)
Students’ self-reflections are consistent with our observations.
Role of calculus???
Results : Study I-2 (2 of 2)
“formula are all involved calculus, if I do not know, I will not understand the meaning of
physics at all…”“Although the set up part is basically physics, you still need certain math. Like the 20% is
math in the set up process …but you could not know what to do…”
“I am not confident if I set up the problem right or wrong…”
“so many numbers and constants to taking account, I get confused, I lose objective of
what I am actually looking for… ““as soon as I set it up, there is no problem”
“can set it up the relations…”“you do not need to do real calculation. So set it up is usually a physics thing. You can still
understand qualitatively…”
21
Phase I: Conclusions‘Horizontal’ Transfer
Students are able to retain their calculus schema.
Students have difficulty associating their physics problem variables into their calculus schema.
22
Phase II: Study II-1Interview, Spring 2005
ParticipantsFive males, three females
Various majors
For each session (two sessions total):Similar format as Study I-2
Do not solve pure calculus problem
Contrast use of “integration” vs. “summation”
Focus on exploring the origin of difficulties
23
Results : Study II-1 (1 of 4)
Consistent with Study I-2 results
When to use integration in physics problems When problems were similar to the examples they had seen in the text (4 out of 7 interviewees)
Could not explain why use integration
Could not solve the contrasting cases
Use integration in terms of adding up the infinitesimally small elements (3 out of 7 interviewees )
“...you can not add up an infinite number…then I used integrate”
“Because it is the example in the book….i do not know
the reason”; “I just know there is integral involved, I
do not know why”
Have difficulty deciding when to activate certain schema
24
Results : Study II-1 (2 of 4)
Difficulties when applying integralsDetermining the variable of integration
Deciding the limits of integration Students usually did not realize they used the wrong limits
Origin of difficultiesPhysics class (majority)
Calculus class
“I know how to integrate it, but it is just figuring out what to integrate,
that is the hard part…”; “…which is really general, but what is ds, what
should substitute to…” ; “These are all constants, I do not know what
should I integrate…”
“…not really to do with my math class. just what variable you put there, cause when I got something to integrate, I know how to integrate it, but it is just figuring out what to integrate, that is the hard part, getting to the part..”“probably from math, because the
concept of physics is pretty simple. Because you can see the concept, I
understand them well. …well, it is not physics is that hard, math is that hard, it
is putting them together is hard, it is writing a equation for what I
understanding is hard.”
25
Results : Study II-1 (3 of 4)
Students prefer to use pre-derived algebraic relationship over calculus relationship
unaware of whenwhen to use integration
Is use of calculus in physics just “plug and chug”?Yes (6 of 8)
No (2 of 8)
riE
πμ2
0= enclosedidsE 0μ=∫
“more confidently use algebra expression to go straight rather than understand this (calculus)”
“ I have to understand or I will be confused”
Again, have difficulty deciding when to activate certain schema
“I do not need to understand it, just how to do it. And I was doing good this way in calculus”
26
Results : Study II-1 (4 of 4)
To facilitate transfer from calculus to physics
Learning how to set-up physics problems
Focus on understanding
Course sequencing
More ‘word’ problems in calculus
“even in calculus, I had to understand why the
differentiation of s2 equal to 2s…”; “why integration and
differentiation works.”
“I do not think they need to go through all the integration
steps, but they need to show how to set
it up, show the different
varieties…so you know what is changing … “
“…in word problem, you need to think about what integral you want
to se up, so they can do that in calculus, that would be helpful, so when you go to physics, you are
learning new material, like electricity, but you already know
calculus.”
27
Phase II : Study II-2Interview, Fall 2006Participants
11 males, 1 female
Volunteers: Selected to represent different exam performance
Covered the required concept 2-3 weeks ago
For each session (two sessions total)Similar format as previous interview
Solve four ‘Jeopardy’ problems
28
Physics ‘Jeopardy’ Problems11Van Heuvelen & Maloney, (1999)
Work backwardEquation physical situation
Graph physical quantity
Why use ‘Jeopardy’ problems“Students can not use formula-centered, plug-and chug problem solving method, they must give meaning to symbols in the equation”11
“Help students to learn to translate between representations in a more robust manner”11
Look closely at how students understand the calculus-based equation in physics
Possible strategy to facilitate the transfer process
Difficult!
29
Sample ‘Jeopardy’ Equation Problems
⎥⎥⎥
⎦
⎤
⎢⎢⎢
⎣
⎡
×××
⋅×× ∫ −
−−6
022
210229
)105(cos)105)(102()1099.8(2
π
θθm
dmmCCmN
( ) ( )
R
rdrrJR
π
πμ
2
20
0 ∫ ⋅
Construct an appropriate physical situation that is consistent with the following expressions.
30
Sample ‘Jeopardy’ Graph ProblemsGiven the graph of E field, what is the electric potential at different points?
-25
-20
-15
-10
-5
0
5
10
15
20
25
0 1 2 3 4 5 6 7 8
x (m)
E (N
/C)
0
1
2
3
4
5
0 1 2 3 4 5 6
x (m)V
(KV)
Given the graph of potential, what is the E field in different regions?
31
Results: Study II-2 (1 of 2)
While solving ‘Jeopardy’ equation problems …Most tried to use units to find the physical quantity.
Some figured out the geometry from variables of integration, others could not.
Most appear to use pattern matching: Cannot explain why.
Most believe ‘Jeopardy’ problems would help understanding.
“I take all the units and convert to what variable
that they look for”
“I look for pieces of terms that I recognize,…, they will
tell what kind of problem they are, I just tend the recognize forms, like
derivative…” ; “I do not know why those formula work, I just use them”
Have difficulty deconstructing and reconstructing their schema
“Just working things backward, you have to understand it better, because if you just start with everything given and plug in the formula, you might get better out it, you might understand it better, but this way
you will understand it really well, because you have to know where is everything
come from”
32
Results: Study II-2 (2 of 2)
While solving ‘Jeopardy’ graph problems …
About half could recognize that…slope of graph ⇒ differentiation
area under curve ⇒ integration
Cannot explain why.“this is kind of thing that I have known so long and
I could not explain”
33
Phase II: Conclusions
‘Vertical’ Transfer
Students have difficulty deciding when to activatewhen to activatetheir calculus schemas.
Have difficulty deconstructingdeconstructing their schemas and constructingconstructingnew schemas based on the problem scenario.
34
Phase III : Faculty InterviewParticipants
Physics2 Faculty
4 Studio Instructors
Mathematics2 Faculty
2 Teaching Assistants
30 minutes interviewExpectation and outcomes of course
35
Results: Phase III (1 of 4)Mathematics faculty
Experienced in teaching calculus
Expectation after ‘Calculus-I’ & ‘Calculus-II’How to do integration and differentiation (4 of 4)Some applications (find maximum/minimum) (2 of 4)
Satisfied with course outcomes
Aware calculus is used in other subjectsEspecially physicsLimited examples of applications
“…I do not have enough background to actually know where
they are generally used”
36
Results: Phase III (2 of 4)Mathematics faculty
Limited use of “Word” Problems10% - 20%
Instructor own reflection
Reviewed past exams (from 2001-2005)
Interested to hear what physicists feel
“students told me that they even do not want to try…something I never understood myself, cause that is the problem that you encounter in everyday life, but for some reason, translate a word problem into a mathematical problem is the big step”
“they do not do well on the word problems, so, as far as on exams, I mean I was trying to put some on them, but I do not make the exam too hard”
37
Results: Phase III (3 of 4)Physics faculty
Experienced in teaching physics
What do you expect from the calculus class?Basic calculus
Do simple mechanically differentiation and integrals
Conceptual understanding
Strategies to overcome students’ conceptual difficulties
Give many examples (time constraints)
Emphasize concepts
Use Visualizations
YES
NO
38
Results: Phase III (4 of 4)Physics faculty
Suggestions for math department
More “word” problems to develop problem solving skills
Focus on conceptual understanding over mechanically doing calculus
“I would be happier if the mathematicians put more
emphasis on the theoretical basis of calculation, in terms of the exercises, more emphasis
on simple problems”
39
Phase III: ConclusionsTo facilitate transfer from calculus to physics
MathematicsFocus more on understanding
More “word” problems
PhysicsMore step by step “setting-up”
Different problem representation, e.g. Jeopardy
AdministratorCourse sequence
40
SummaryPhase I: Phase I: ‘‘HorizontalHorizontal’’ TransferTransfer
Students appear to retain their schema to solve calculus problems.Students have difficulty associating their physics problem variables into their calculus schema.
Phase II: Phase II: ‘‘VerticalVertical’’ TransferTransferStudents have difficulty deciding when to activate appropriate calculus schemas.Students have difficulty in deconstructing their schemas and constructing new ones based on the problem scenario.
Phase III: Instructional StrategiesPhase III: Instructional StrategiesMath : Focus on understanding, word problems.Physics : Focus on setting up, other problem types.
41
Future PlansInvestigate transfer across other domains e.g.
Physics to Engineering
Other disciplines
Are issues similar or different?
Develop instructional strategies to facilitate students’ ‘horizontal’ and ‘vertical’ transfer from calculus to physics.
42
Characteristics of Instructional Strategies
Balance ‘horizontal’ and ‘vertical’ transferFollow an ‘Optimal Adaptability Corridor’9
Adapt proven pedagogical strategies e.g.Small steps of Model Development followed by Model Deployment.10
Scaffolded learning in Zones of Proximal Development.12
Emphasize multiple representations‘Zone of Proximal
Development’ is the range of concepts that a student can learn with assistance of a
teacher
12 Vygotsky (1978)10 Hestenes (1987)
9 Schwartz, Bransford & Sears (2005)
43
In Terms of Our Framework…
Horizontal
Ver
tica
l
What we currently try to do…What we shouldshould try to do…
Mathematics
Mathematics
Physics
Physics
ModelDevelopment
ModelDevelopment
Model Deployment
Model Deployment
‘‘Optimal
Optimal
Adaptability
Adaptability
Corridor
Corridor’’
99
99 Schwartz, Bransford & Sears (2005)Schwartz, Bransford & Sears (2005)
Mathematics
Mostly ‘horizontal’
Scaffolded learning inZone of Proximal Dev.
Phy
sics
Mos
tly
‘ver
tica
l’
1010 Hestenes (1987)Hestenes (1987) 1212 VygotskyVygotsky (1978)(1978)
44
Thank You!
Lili CuiPhysics Education Research Group
Department of PhysicsKansas State University
[email protected]://www.phys.ksu.edu/personal/lili