8,859 research outputs found
An Examination of Social Adaptation Processes of Vietnamese Adolescents
The purpose of the study was to examine the factors that affect the ways in which Vietnamese youth feel about themselves and their place in society. More specifically, the purpose was to determine the relationship between sociocultural factors (L e. language proficiency, length of residence, socioeconomic class, ethnic identity, and cultural continuity) and such person-oriented variables as depression and alienation. Thrity-one college and fifteen high school students responded to a series of questions about themselves, family, relationships, personality, and achievement motivation. It was found that perceived problems with one\u27s ethnic group, cultural continuity, and parental attitudes toward schooling significantly predicted depression. Degree of attachment to one\u27s ethnic community, English speaking and writing abilities, and outlets for derpession tended to predict future outlook or feelings of hope versus alienation. Several variables were highly predictive of acculturation. Some of those variables are native language ability, English speaking and writing ability, outlets for depression, and perceived problems with one\u27s ethnic group. Implications of the findings for Vietnamese youth and future directions are discussed
Sums and differences of correlated random sets
Many fundamental questions in additive number theory (such as Goldbach's
conjecture, Fermat's last theorem, and the Twin Primes conjecture) can be
expressed in the language of sum and difference sets. As a typical pair of
elements contributes one sum and two differences, we expect that for a finite set . However, in 2006 Martin and O'Bryant showed that a
positive proportion of subsets of are sum-dominant, and Zhao
later showed that this proportion converges to a positive limit as . Related problems, such as constructing explicit families of
sum-dominant sets, computing the value of the limiting proportion, and
investigating the behavior as the probability of including a given element in
to go to zero, have been analyzed extensively.
We consider many of these problems in a more general setting. Instead of just
one set , we study sums and differences of pairs of \emph{correlated} sets
. Specifically, we place each element in with
probability , while goes in with probability if
and probability if . If , we
call the pair a \emph{sum-dominant -pair}. We prove
that for any fixed in , is a
sum-dominant -pair with positive probability, and show that
this probability approaches a limit . Furthermore, we show that
the limit function is continuous. We also investigate what
happens as decays with , generalizing results of Hegarty-Miller on phase
transitions. Finally, we find the smallest sizes of MSTD pairs.Comment: Version 1.0, 19 pages. Keywords: More Sum Than Difference sets,
correlated random variables, phase transitio
A Standardized Orientation Course on Central Line Placement Leads to Persistent Knowledge Improvement.
Sets Characterized by Missing Sums and Differences in Dilating Polytopes
A sum-dominant set is a finite set of integers such that .
As a typical pair of elements contributes one sum and two differences, we
expect sum-dominant sets to be rare in some sense. In 2006, however, Martin and
O'Bryant showed that the proportion of sum-dominant subsets of
is bounded below by a positive constant as . Hegarty then extended
their work and showed that for any prescribed , the
proportion of subsets of that are missing
exactly sums in and exactly differences in
also remains positive in the limit.
We consider the following question: are such sets, characterized by their
sums and differences, similarly ubiquitous in higher dimensional spaces? We
generalize the integers in a growing interval to the lattice points in a
dilating polytope. Specifically, let be a polytope in with
vertices in , and let now denote the proportion of
subsets of that are missing exactly sums in and
exactly differences in . As it turns out, the geometry of
has a significant effect on the limiting behavior of . We define
a geometric characteristic of polytopes called local point symmetry, and show
that is bounded below by a positive constant as if
and only if is locally point symmetric. We further show that the proportion
of subsets in that are missing exactly sums and at least
differences remains positive in the limit, independent of the geometry of .
A direct corollary of these results is that if is additionally point
symmetric, the proportion of sum-dominant subsets of also remains
positive in the limit.Comment: Version 1.1, 23 pages, 7 pages, fixed some typo
A Standardized Orientation Course on Central Line Placement Leads to Persistent Knowledge Improvement
Central and Peripheral Nervous System Demyelination Following Mycoplasma Pneumonia Infection With Review of Literature
Obsolete or Essential? Gastrointestinal Decontamination in Severe Bupropion Ingestions: A Case Series
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