Transcript What did you mean? What did they see?

Visual Misconceptions: What did you
mean? What did they see?
How do you know?
Michelle Hall
Isostasy
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A supposed equality
existing in vertical sections
of the earth, whereby the
weight of any column from
the surface of the earth to
a constant depth is
approximately the same as
that of any other column of
equal area, the equilibrium
being maintained by
plastic flow of material
from one part of the earth
to another.
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NASA.gov
Isostasy
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A state of equilibrium,
resembling flotation, in
which segments of
Earth's crust float (on
liquid mantle material)
at levels determined
by their thickness and
density. Isostatic
equilibrium is attained
by flow of material in
the mantle.
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isu.edu
Isostasy
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The equilibrium
maintained between
the gravity tending
to depress and the
buoyancy tending to
raise a given
segment of the
lithosphere as it
floats above the
asthenosphere.
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Modeling tool from umich.edu
mit.edu
Visualizations Tell Stories
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Mantle is molten.
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Mid-ocean ridges are locations of underwater
volcanoes.
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Where do the volcanoes go as the plate moves away
from the ridge?
Magma is stored in large open chambers in the
crust; flows to fill in open spaces.
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If it is not molten, where does magma come from? How
does the mantle convect?
If there are no magma “chambers” how do we create
giant batholiths?
Students visualize the objects but not the process.
Flow in the (Fluid?) Mantle
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Conveyor belt flow model with no sense of time
How is oceanic lithosphere
formed?
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Complete melting beneath ridges
No labeling of layers
No temperature or density information
Magma fills
empty spaces?
Magma intrusions
causing no
metamorphism of
surrounding area
 The space
problem is poorly
addressed
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Visualizations Translate Data into
Models
Where is the deepest seafloor?
Applying the Research
What causes confusion?
 Metaphors,
analogies and models
that get merged with incorrect or
incomplete current and prior
understandings?
 Ineffective / incomplete graphics?
 Poor spatial skills?
 All of the above.
Challenges of Visualizing Earth
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Temporal and spatial scales cannot be modeled
in a laboratory
99.9% of Earth is inaccessible
Visualizing the 3-D and 4-D processes in
traditional 2-D representations requires
advanced spatial reasoning
Process-oriented thinking requires fundamental
knowledge of physics, chemistry and biology
How do we learn?
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Goal-oriented - motivation and interest are high
Failure driven - have identified a knowledge gap
and need to fill it
Case-based - draws upon previous knowledge
and experience
By doing - knowledge is acquired through
interaction between the self and the world
• Brandsford et al, 2000; Piaget, 1983; Shank et al, 1995
Visualizations improve learning
when they …
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Incorporate learner controlled manipulation of
real or computer simulated models
Direct the learner to observe effects of
changes in an objects orientation on its 2D
image.
Encourage hypothesis testing about 2D and
3D objects
Require externalizing mental images
Provide practice in mentally rotating an object
Encourage visualizing the interior of bodies
Lord, 1985; Ben-Chaim et al, 1988;
Duesbury and O’Neil, 1996; Kali and Orion, 1997
Strengths and Weaknesses of
Visual Learning
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Strengths
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Information in multiple modes improves
comprehension
Organization improves memory
Complex relationships or processes can be easier
to understand
Weaknesses
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Simple diagrams cannot accurately convey
complexity of process or its time scale
Complex diagrams are too advanced for most
learners
Spatial Ability
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Topological develops early
Projective adolescent through
adult
Euclidean adolescent through
adult
Miller Indices 111
Developing Spatial Abilities
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Spatial skills vary with age and experience (Linn
and Petersen, 1985)
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Spatial skills can be improved with training (Blade
and Watson, 1955; Lord, 1985; Kali et al., 1996)
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Skill differences are minimized or disappear
when time limitations on tests are removed (Linn
and Petersen, 1985)
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Students level of spatial ability directly affects
interpretation of a model (McClurg et al., 1993)
Evaluating Spatial Skills
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Mental Rotation Test - tests projective skills
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Surface Development Test - tests Euclidean
skills
MS thesis of T. Baldwin
Methods
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Conduct pre- and post-tests of spatial skills in
introductory courses to determine spatial
abilities of groups and measure any changes.
Geoscience majors had extensive laboratory
exercises (3 hrs/week) using maps, interactive
computer models of Earth objects and
processes, and field trips
Non-majors completed 8-10 hours of homework
assignments, some with maps.
Mental Rotation Skills
Pre-Test
Post-Test
Nonmajors
x 6.8
sd 4.2
n 174
x 8.2
sd 5.1
n 174
Majors
x 7.9
sd 5.5
n 55
x 11.0
sd 5.8
n 55
Surface Development Skills
Pre-Test
Post-Test
Nonmajors
x 1.6
sd 12.3
n 164
x 3.1
sd 14.1
n 164
Majors
x 14.8
sd 10.9
n 48
x 18.0
sd 9.5
n 48
Conclusion
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Analysis of spatial abilities of undergraduate
students suggests the need to evaluate
teaching strategies to ensure that students can
interpret and understand visual imagery used in
lectures.
Development of visualizations would be
improved by more focused approach to content.
Simple viewing of visualizations is passive
learning and likely no more effective than
passive listening to a lecture.
Interpretation Without
Context or Culture
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Si usted pudiera predecir lo que va a pasar en el futuro,
cuantas cosas cambiaria en su vida para prepararse?
literally translates to
If you could predict what is going to pass in the future,
as many foreign exchange things in its life to be
prepared?
but means
If you could predict the future, how many things would
you change in your life to better prepare yourself?