STUDENT RESEaRch SympoSiUm 2010 - Graduate and Research ...

196
AbstrActs
#444 11:15
Exploring the Spatial Resolution Limitations of Satellite
Imagery for Slum Detection in Accra, Ghana
Justin Stoler, Geography (D)
John Weeks, Geography
Analysis of remote sensing imagery has the potential for identifying
and categorizing slums, but little research has been conducted
on how differing spatial resolutions or classification techniques
affect the results of this type of analysis. This study assesses
the correlation between satellite-derived land cover and censusderived
socioeconomic variables in Accra, Ghana to determine
whether the relationship between these variables is altered with
a change in spatial resolution or scale. An ASTER composite
and Landsat TM composite, with spatial resolution of 15 and 30
meters respectively, were used to conduct the comparison. Land
cover was classified and converted into percentages for each
Enumeration Area in Accra using a sub-pixel modeling classification
technique known as spectral mixture analysis (SMA). Correlation
and regression analyses were conducted to compare the
SMA results to a slum index created from various socio-economic
data taken from the Census of Ghana, as well as to data derived
from a “hard” per-pixel classification of a 2.4 m Quickbird image.
The analysis identified a significant link between vegetation
fraction and the slum index, however results suggested that this
variable alone cannot confidently predict slum presence, although
the use of the spatial error model does improve the results. The
SMA-derived ASTER data proved to be a sufficient substitute for
the QB data when using land cover fractions as a proxy for slum
presence, in many instances outperforming the higher resolution
data. While SMA might be useful for deriving land cover fractions
from ASTER imagery, the SMA-derived TM data did not exhibit
strong relationships to the slum index and should not be considered
for this type of demographic analysis.
Session D-15
Oral Presentation: Philosophy
Saturday, March 5, 2010, 10:15 am
Location: Quetzalcoatl B
#445 See Session B-13
#446 10:15
Burge, Marty, and Fallibility
Jonathan Hecht, Philosophy (U)
Angelo Corlett, Philosophy
In recent years, a topic of great controversy has been the claim
by Tyler Burge that cogito-like judgments, or second-order
STUDENT RESEARCH SYMPOSIUM 2010
judgments, are self-verifying and infallible. He avers that “these
sort of judgments are self-verifying in an obvious way: making
these judgments itself makes them true” infallibly. A second-order
judgment is a thought about a thought. This can take the form
of propositions such as, “I think water is wet”. Burge claims that
it cannot be erroneous in its correspondence to the first-order
belief that one thinks water is wet, if one has such a thought.
There have been a number of counterarguments to this claim,
and responses to these counterarguments. I believe that in the
controversy, a relatively simple argument against Burge has been
overlooked, which can be demonstrated by a thought experiment.
Although Burge maintains the discussion of second-order judgments
using the form “I think water is wet”, I shall be discussing
it as “I think I think water is wet”, with that representing the
second-order judgment and “I think water is wet” representing
the first order thought. One possible formulation of the thought
experiment can be explained symbolically as follows: Let P 1 be
proposition 1, P 2 be proposition 2, B m be the belief of Marty, ¬B m
be the disbelief of Marty, S be the said thing, A be lawyer A, B be
lawyer B, and J m be the second-order judgment of Marty.
S(A,P 1) (B m(P 1)) (J m(B m(P 1)))
S(B, P 2) (¬B m(P 2)) (J m(¬B m(P 2))
S(A, P 2=P 1) (B m(P 2=P 1)) (J m(B m(P 2=P 1)))
Therefore, B m(P 1) (¬B m(P 1)) (J m(B m(P 1))) (J m(¬B m(P 1)))
B m(B m) (¬B m(P 1)) is impossible
Therefore, Jm does not correspond to Bm Therefore, second-order judgments are not infallible.
#447 10:30
On the Semantics of Singular Statements in Aristotle
Kevin Lopez, Philosophy (M)
Mark Wheeler, Philosophy
Aristotle appears to endorse the semantical claim that true singular
affirmations guarantee the existence of their subjects: ostensible
support for this claim can be found at Categories 13b12-35.
However, it has frequently been noted that Aristotle shows signs
of rejecting this position at De Interpretatione 21a18-33. In this
passage it is stated that ‘Homer is’ cannot be inferred from
‘Homer is a poet’ and this, Aristotle says, is because ‘is’ holds
accidentally of Homer. One of the questions that will be answered
is what exactly Aristotle means by ‘accidentally’.. How ought
these two texts to be reconciled? First, I take up Michael Wedin’s
attempts to explain the hermeneutical inconsistency. Immediately
following my criticisms, I provide an interpretation that corrects
and develops from Wedin’s position. Wedin expresses a fundamental
insight: the De Interpretatione passage concerns rules