8,113 research outputs found
E-testing in Graduate Courses: Reflective Practice Case Studies
Do testing and exam conditions make a difference in final exam grades? Do testing “out of class” and “in class” produce different results over the same courses? Several graduate courses (N = 84) were tested under different and varying conditions. The majority of students were international, where English was a second language. In general, the “online” e-testers performed at a higher level than the ““in class”” testers with and without any time restrictions while test taking. Tentative implications might be that online exams (less controls) yield grades which are possibly higher, and may or may not be “grade inflated.” On the other hand, possibly less controls in exams yield more learning and higher retention of course content
Presidential Elections - The Right to Vote and Access to the Ballot
The following article is a tripartite effort by Mitchell Berger and Grace E. Robson, members of the Florida Bar; John B. Anderson, a member of the Nova Southeastern University\u27s Shepard Broad Law Center faculty; and a team of two of the students at that law school, Jason Blank and Tom Brogan, to examine the subject of ballot access for non-major party candidates in presidential elections in the wake of the recent decision of the Supreme Court of Florida in Reform Party of Florida v. Black.\u27 Mr. Berger has furnished a critical analysis of that decision. Our team of students has catalogued the ballot access laws of the fifty states and the District of Columbia. John B. Anderson has reviewed United States Supreme Court decisions on the subject of ballot access specifically, and then also more generally on the way in which they reflect on the electoral process; a process which for a century and a half has been dominated by our two major parties. His criticism of the resulting duopoly of political power and control should be attributed to him alone and not to the other members of this collaborative effort. However, both Mr. Berger and Mr. Anderson support the idea of a constitutional amendment putting forth an affirmative right to vote as both necessary and desirable as a predicate for any effort to achieve a more uniform approach to ballot access in future presidential contests. We also join in our appreciation for the research assistance of Messrs. Blank and Brogan and their contribution to our joint effort
Extreme alpha-clustering in the 18O nucleus
The structure of the 18O nucleus at excitation energies above the alpha decay
threshold was studied using 14C+alpha resonance elastic scattering. A number of
states with large alpha reduced widths have been observed, indicating that the
alpha-cluster degree of freedom plays an important role in this N not equal Z
nucleus. However, the alpha-cluster structure of this nucleus is very different
from the relatively simple pattern of strong alpha-cluster quasi-rotational
bands in the neighboring 16O and 20Ne nuclei. A 0+ state with an alpha reduced
width exceeding the single particle limit was identified at an excitation
energy of 9.9+/-0.3 MeV. We discuss evidence that states of this kind are
common in light nuclei and give possible explanations of this feature.Comment: 4 pages, 2 figures, 1 table. Resubmission with minor changes for
clarity, including removal of one figur
Observables in the Decays of B to Two Vector Mesons
In general there are nine observables in the decay of a B meson to two vector
mesons defined in terms of polarization correlations of these mesons. Only six
of these can be detected via the subsequent decay angular distributions because
of parity conservation in those decays. The remaining three require the
measurement of the spin polarization of one of the decay products.Comment: 12 pages, no figur
Quantum Monte Carlo calculations of six-quark states
The variational Monte Carlo method is used to find the ground state of six
quarks confined to a cavity of diameter R_c, interacting via an assumed
non-relativistic constituent quark model (CQM) Hamiltonian. We use a flux-tube
model augmented with one-gluon and one-pion exchange interactions, which has
been successful in describing single hadron spectra. The variational wave
function is written as a product of three-quark nucleon states with
correlations between quarks in different nucleons. We study the role of quark
exchange effects by allowing flux-tube configuration mixing. An accurate
six-body variational wave function is obtained. It has only ~13% rms
fluctuation in the total energy and yields a standard deviation of ~<.1%; small
enough to be useful in discerning nuclear interaction effects from the large
rest mass of the two nucleons. Results are presented for three values of the
cavity diameter, R_c=2, 4, and 6 fm. They indicate that the flux-tube model
Hamiltonian with gluon and pion exchange requires revisions in order to obtain
agreement with the energies estimated from realistic two-nucleon interactions.
We calculate the two-quark probability distribution functions and show how they
may be used to study and adjust the model Hamiltonian.Comment: 49 pages, 13 figures, submitted to Phys. Rev.
The Unfulfilled Potential of Data-Driven Decision Making in Agile Software Development
With the general trend towards data-driven decision making (DDDM),
organizations are looking for ways to use DDDM to improve their decisions.
However, few studies have looked into the practitioners view of DDDM, in
particular for agile organizations. In this paper we investigated the
experiences of using DDDM, and how data can improve decision making. An emailed
questionnaire was sent out to 124 industry practitioners in agile software
developing companies, of which 84 answered. The results show that few
practitioners indicated a widespread use of DDDM in their current decision
making practices. The practitioners were more positive to its future use for
higher-level and more general decision making, fairly positive to its use for
requirements elicitation and prioritization decisions, while being less
positive to its future use at the team level. The practitioners do see a lot of
potential for DDDM in an agile context; however, currently unfulfilled
An optical-IR jet in 3C133
We report the discovery of a new optical-IR synchrotron jet in the radio
galaxy 3C133 from our HST/NICMOS snapshot survey. The jet and eastern hotspot
are well resolved, and visible at both optical and IR wavelengths. The IR jet
follows the morphology of the inner part of the radio jet, with three distinct
knots identified with features in the radio. The radio-IR SED's of the knots
are examined, along with those of two more distant hotspots at the eastern
extreme of the radio feature. The detected emission appears to be synchrotron,
with peaks in the NIR for all except one case, which exhibits a power-law
spectrum throughout.Comment: ApJ accepted. 14 pages, 6 figure
Understanding Search Trees via Statistical Physics
We study the random m-ary search tree model (where m stands for the number of
branches of a search tree), an important problem for data storage in computer
science, using a variety of statistical physics techniques that allow us to
obtain exact asymptotic results. In particular, we show that the probability
distributions of extreme observables associated with a random search tree such
as the height and the balanced height of a tree have a traveling front
structure. In addition, the variance of the number of nodes needed to store a
data string of a given size N is shown to undergo a striking phase transition
at a critical value of the branching ratio m_c=26. We identify the mechanism of
this phase transition, show that it is generic and occurs in various other
problems as well. New results are obtained when each element of the data string
is a D-dimensional vector. We show that this problem also has a phase
transition at a critical dimension, D_c= \pi/\sin^{-1}(1/\sqrt{8})=8.69363...Comment: 11 pages, 8 .eps figures included. Invited contribution to
STATPHYS-22 held at Bangalore (India) in July 2004. To appear in the
proceedings of STATPHYS-2
Analytic solution of the fractional advection diffusion equation for the time-of-flight experiment in a finite geometry
A general analytic solution to the fractional advection diffusion equation is
obtained in plane parallel geometry. The result is an infinite series of
spatial Fourier modes which decay according to the Mittag-Leffler function,
which is cast into a simple closed form expression in Laplace space using the
Poisson summation theorem. An analytic expression for the current measured in a
time-of-flight experiment is derived, and the sum of the slopes of the two
respective time regimes on logarithmic axes is demonstrated to be -2, in
agreement with the well known result for a continuous time random walk model.
The sensitivity of current and particle number density to variation of
experimentally controlled parameters is investigated in general, and the
results applied to analyze selected experimental data.Comment: 10 pages, 6 figure
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