Showing papers by "Georgia State University published in 2003"

Trust and TAM in online shopping: an integrated model

Abstract: A separate and distinct interaction with both the actual e-vendor and with its IT Web site interface is at the heart of online shopping Previous research has established, accordingly, that online purchase intentions are the product of both consumer assessments of the IT itself-specifically its perceived usefulness and ease-of-use (TAM)-and trust in the e-vendor But these perspectives have been examined independently by IS researchers Integrating these two perspectives and examining the factors that build online trust in an environment that lacks the typical human interaction that often leads to trust in other circumstances advances our understanding of these constructs and their linkages to behavior Our research on experienced repeat online shoppers shows that consumer trust is as important to online commerce as the widely accepted TAM use-antecedents, perceived usefulness and perceived ease of use Together these variable sets explain a considerable proportion of variance in intended behavior The study also provides evidence that online trust is built through (1) a belief that the vendor has nothing to gain by cheating, (2) a belief that there are safety mechanisms built into the Web site, and (3) by having a typical interface, (4) one that is, moreover, easy to use

Surface plasmon amplification by stimulated emission of radiation: quantum generation of coherent surface plasmons in nanosystems.

Abstract: We make a step towards quantum nanoplasmonics: surface plasmon fields of a nanosystem are quantized and their stimulated emission is considered. We introduce a quantum generator for surface plasmon quanta and consider the phenomenon of surface plasmon amplification by stimulated emission of radiation (spaser). Spaser generates temporally coherent high-intensity fields of selected surface plasmon modes that can be strongly localized on the nanoscale, including dark modes that do not couple to far-zone electromagnetic fields. Applications and related phenomena are discussed.

Empirical testing of a model of online store atmospherics and shopper responses

Abstract: This study empirically tests a model that proposes that the atmospheric cues of the online store influence shoppers' emotional and cognitive states, which then affect their shopping outcomes. The results support the model propositions and show a significant effect of site atmospherics on shopper attitudes, satisfaction, and various approach/avoidance behaviors as a result of the emotions experienced during the shopping episode. In addition, the findings confirm the hypothesized moderating effects of two individual traits, namely, involvement and atmospheric responsiveness. The results underscore the role that online store atmospherics play in creating positive reactions from shoppers and demonstrate that these positive reactions will be more pronounced under certain conditions. © 2003 Wiley Periodicals, Inc.

Self-similar chain of metal nanospheres as an efficient nanolens.

Abstract: As an efficient nanolens, we propose a self-similar linear chain of several metal nanospheres with progressively decreasing sizes and separations. To describe such systems, we develop the multipole spectral expansion method. Optically excited, such a nanolens develops the nanofocus ("hottest spot") in the gap between the smallest nanospheres, where the local fields are enhanced by orders of magnitude due to the multiplicative, cascade effect of its geometry and high Q factor of the surface plasmon resonance. The spectral maximum of the enhancement is in the near-ultraviolet region, shifting toward the red region as the separation between the spheres decreases. The proposed system can be used for nanooptical detection, Raman characterization, nonlinear spectroscopy, nanomanipulation of single molecules or nanoparticles, and other applications.

Disentangling the "whys" from the "whats" of aggressive behaviour

Abstract: We examined the validity of a measurement system for the study of aggression that distinguishes among four principle dimensions of aggressive behaviour: overt and relational aggression (i.e., the "whats") and instrumental and reactive aggression (i.e., the "whys"). The sample comprised 1723 adolescents (Grades 5 through 10) from Berlin, Germany. The internal validity of the measurement system was strongly supported, revealing four discrete dimensions of aggression: two overriding forms (overt and relational) and two underlying functions (instrumental and reactive). The differential and unique patterns of criterion-related validity strongly supported the distinctions among the constructs. The importance of disentangling these dimensions in understanding the development of aggressive behaviour is discussed.

Prevalence and predictors of women's experience of psychological trauma during childbirth.

Abstract: Background: The increased acceptance of the prevalence of trauma in human experience as well as its psychological consequences has led to revisions of diagnostic criteria for the disorder. The three purposes of this study were to examine the rates at which women experienced psychological trauma in childbirth, to explore possible causal factors, and to examine possible factors in the development of the disorder. Methods: One hundred and three women from childbirth education classes in the Atlanta metropolitan area completed a survey in late pregnancy and a follow-up interview approximately 4 weeks after the birth. Results: The childbirth experience was reported as traumatic by 34 percent of participants. Two women (1.9%) developed all the symptoms needed to diagnose posttraumatic stress disorder, and 31 women (30.1%) were partially symptomatic. Regression analysis showed that antecedent factors (e.g., history of sexual trauma and social support) and event characteristics (e.g., pain in first stage of labor, feelings of powerlessness, expectations, medical intervention, and interaction with medical personnel) were significant predictors of perceptions of the childbirth as traumatic. The pain experienced during the birth, levels of social support, self-efficacy, internal locus of control, trait anxiety, and coping were significant predictors of the development of posttraumatic stress disorder symptoms after the birth. Conclusions: These findings suggest several intervention points for health care practitioners, including careful prenatal screening of past trauma history, social support, and expectations about the birth; improved communication and pain management during the birth; and opportunities to discuss the birth postpartum. (BIRTH 30:1 March 2003)

Elliptic flow of identified hadrons in [formula presented] collisions at [formula presented]

Abstract: The anisotropy parameter (v(2)), the second harmonic of the azimuthal particle distribution, has been measured with the PHENIX detector in Au+Au collisions at roots(NN)=200 GeV for identified and inclusive charged particle production at central rapidities (eta 2 GeV/c, in marked contrast to the predictions of a hydrodynamical model. A quark-coalescence model is also investigated.

A Comparison of International and Domestic New Ventures

Abstract: Differences between international new ventures (INVs) and domestic new ventures (DNVs) were examined using a sample of 214 IPO new ventures (ventures 6 years old or less). INVs were found to be significantly different on the basis of their entrepreneurial team experience, strategy, and industry structure. Specifically, the entrepreneurial team of INVs exhibited higher levels of previous international and industry experience. The strategies of INVs were more aggressive, and they operated in more channels of distribution than did DNVs. INVs competed on the basis of differentiation, placing greater emphasis on product innovation, quality, service, and marketing as strategic weapons. In addition, INVs were more likely than DNVs to operate in industries characterized by a high degree of global integration.

The New Face of Government: Citizen-Initiated Contacts in the Era of E-Government

Abstract: Dramatic developments in information technology are transforming society, challenging our nation’s many governments to keep pace. As e-governance grows in popularity, Web pages could well become the new face of government. But how are citizens responding? We suggest that government Web sites may provide a new vehicle for citizen-initiated contacts with government, and, drawing from the literature on those traditional contacts, we propose a number of hypotheses on citizen interaction with government via the Web. To test those hypotheses, we examine data from a survey concerning how Georgians are contacting government via the Web. We find that citizen visits to governmental Web sites are increasingly common, and as such appear to have become a major new form of the traditional citizen-initiated contact. To date, however, most of these Web contacts have been made only to obtain information, thus lacking the interactive quality crucial to other citizen-initiated contacts. As an encouraging finding for government, visitors to governmental Web sites appear to be mostly pleased with their experiences, rating those sites as at least comparable in quality to other Web sites. A discouraging finding, however, is that the demographics of these visitors suggest cause for concern, since the digital divide is even more pronounced among government Web site visitors than among Internet users in general. In the concluding section, we discuss the implications of the findings for government and for future research. One of the most remarkable and dramatic changes in recent decades has been the explosion of interest in the Internet, with the phenomenon of e-commerce—unheard of only a decade ago—becoming in just a few years a principal growth area in the American economy. As use of the Web by the private sector has grown, the public sector has followed closely behind, and virtually all large U.S. governments and their agencies—federal, state, and local —now having their own Web sites. As public-sector Web sites proliferate and expand in function, they are rapidly becoming a new aspect of government. Many citizens who previously would visit or call gov

Suppressed π0 Production at Large Transverse Momentum in Central Au + Au Collisions at √sNN = 200 GeV

Abstract: Transverse momentum spectra of neutral pions in the range 1 < p_T < 10 GeV/c have been measured at mid-rapidity by the PHENIX experiment at RHIC in Au+Au collisions at sqrt(s_NN) = 200 GeV. The pi^0 multiplicity in central reactions is significantly below the yields measured at the same sqrt(s_NN) in peripheral Au+Au and p+p reactions scaled by the number of nucleon-nucleon collisions. For the most central bin, the suppression factor is ~2.5 at p_T = 2 GeV/c and increases to ~4-5 at p_T ~= 4 GeV/c. At larger p_T, the suppression remains constant within errors. The deficit is already apparent in semi-peripheral reactions and increases smoothly with centrality.

The Mythology of Privatization in Contracting for Social Services

Abstract: States and municipalities have privatized services in an effort to improve their cost-effectiveness and quality. Competition provides the logical foundation for an expectation of cost savings and quality improvements, but competition does not exist in many local marketplaces—especially in the social services, where governments contract primarily with nonprofit organizations. As government increases its use of contracting, it simultaneously reduces its own public-management capacity, imperiling its ability to be a smart buyer of contracted goods and services. This article examines two questions about the privatization of social services based on interviews conducted with public and nonprofit managers in New York state: Does social services contracting exist in a competitive environment? And do county governments have enough public-management capacity to contract effectively for social services? The findings suggest an absence of competition and public-management capacity, raising the question of why governments contract when these conditions are not met.

Finance and the Sources of Growth at Various Stages of Economic Development

Abstract: This paper studies the effects of financial development on the sources of growth in different groups of countries. Recent theoretical work shows that financial development may affect productivity and capital accumulation in different ways in industrial versus developing countries. This hypothesis is tested with panel data from 74 countries using GMM dynamic panel techniques. Results are consistent with the hypothesis: finance has a strong positive influence on productivity growth primarily in more developed economies. In less developed economies, the effect of finance on output growth occurs primarily through capital accumulation.

PHENIX detector overview

Abstract: The PHENIX detector is designed to perform a broad study of A-A, p-A, and p-p collisions to investigate nuclear matter under extreme conditions A wide variety of probes, sensitive to all timescales, are used to study systematic variations with species and energy as well as to measure the spin structure of the nucleon Designing for the needs of the heavy-ion and polarized-proton programs has produced a detector with unparalleled capabilities PHENIX measures electron and muon pairs, photons, and hadrons with excellent energy and momentum resolution The detector consists of a large number of subsystems that are discussed in other papers in this volume The overall design parameters of the detector are presented (C) 2002 Elsevier Science BV All rights reserved

Does a Seller’s eCommerce Reputation Matter? Evidence from eBay Auctions

Abstract: With internet commerce, a buyer cannot directly examine the product and so must rely upon the accuracy and reliability of the seller in deciding whether and how much to bid. In this setting, the seller’s reputation can become an important factor in the bid. This paper examines the impact of the seller’s reputation on the willingness of buyers to bid on items sold via internet auctions, using a 1999 mint condition U.S. $5 gold coin whose average price was $32.73. The empirical results show that the seller’s reputation has a positive, statistically signi¢cant, but small impact on the price.

Black-White Differences in Attitudes toward Homosexuality and Gay Rights

Abstract: Black homophobia has been cited as a contributing factor in slowing mobilization against AIDS in the African-American community, as an obstacle to black lesbians and gay men in coming to terms with their sexuality, and as a challenge to the legitimacy of the gay rights movement. Yet evidence that blacks are more homophobic than whites is quite limited. This article uses responses from almost seven thousand blacks and forty-three thousand whites in 31 surveys conducted since 1973 to give more definitive answers on black-white attitudinal differences and their demographic roots. Despite their greater disapproval of homosexuality, blacks' opinions on sodomy laws, gay civil liberties, and employment discrimination are quite similar to whites' opinions, and African Americans are more likely to support laws prohibiting antigay discrimination. Once religious and educational differences are controlled, blacks remain more disapproving of homosexuality but are moderately more supportive of gay civil liberties and markedly more opposed to antigay employment discrimination than are whites. Yet religion, education, gender, and age all have weaker impacts on black than on white attitudes, suggesting that black and white attitudes have different roots

Absence of suppression in particle production at large transverse momentum in √sNN = 200 GeV d + Au collisions

Abstract: Transverse momentum spectra of charged hadrons with p(T)<8 GeV/c and neutral pions with p(T)<10 GeV/c have been measured at midrapidity by the PHENIX experiment at BNL RHIC in d+Au collisions at sqrt[s(NN)]=200 GeV. The measured yields are compared to those in p+p collisions at the same sqrt[s(NN)] scaled up by the number of underlying nucleon-nucleon collisions in d+Au. The yield ratio does not show the suppression observed in central Au+Au collisions at RHIC. Instead, there is a small enhancement in the yield of high momentum particles.

Comparisons and validation of statistical clustering techniques for microarray gene expression data

Abstract: Motivation: With the advent of microarray chip technology, large data sets are emerging containing the simultaneous expression levels of thousands of genes at various time points during a biological process Biologists are attempting to group genes based on the temporal pattern of their expression levels While the use of hierarchical clustering (UPGMA) with correlation ‘distance’ has been the most common in the microarray studies, there are many more choices of clustering algorithms in pattern recognition and statistics literature At the moment there do not seem to be any clear-cut guidelines regarding the choice of a clustering algorithm to be used for grouping genes based on their expression profiles Results: In this paper, we consider six clustering algorithms (of various flavors!) and evaluate their performances on a well-known publicly available microarray data set on sporulation of budding yeast and on two simulated data sets Among other things, we formulate three reasonable validation strategies that can be used with any clustering algorithm when temporal observations or replications are present We evaluate each of these six clustering methods with these validation measures While the ‘best’ method is dependent on the exact validation strategy and the number of clusters to be used, overall Diana appears to be a solid performer Interestingly, the performance of correlation-based hierarchical clustering and model-based clustering (another method that has been advocated by a number of researchers) appear to be on opposite extremes, depending on what validation measure one employs Next it is shown that the group means produced by Diana are the closest and those produced by UPGMA are the farthest from a model profile based on a set of hand-picked genes Availability: S+ codes for the partial least squares based clustering are available from the authors upon request All ∗ To whom correspondence should be addressed other clustering methods considered have S+ implementation in the library MASS S+ codes for calculating the validation measures are available from the authors upon request The sporulation data set is publicly available at

The Relationship between Overconfidence and the Introduction of Risky Products: Evidence from a Field Study

Abstract: To date, no field research has examined the effects of overconfidence on ill-structured decisions made by managers, such as product introductions. We explored this gap in the literature and found, ...

Gender And Elder Care In China: The Influence of Filial Piety and Structural Constraints

Abstract: The authors explore the changing dynamics of gendered familial caregiving in urban China within the context of economic reforms and the continued cultural influence of xiao (filial piety). Data collected in China through interviews with 110 familial caregivers were used to examine cultural and structural influences on the caregiving behavior of adult children. Results from multiple regression analyses provide evidence of a gendered division of parental care tasks, a decline in the patrilocal tradition of caregiving, and a strong social pressure that influences caregiving behavior. Structural factors linked to caregiving performance included family size, lack of pensions for elders, and caregivers’ employment status and income. Findings portend deleterious effects for the women who are now caregivers as they are likely to live longer but be more financially dependent and have fewer children available to help them.

Novel bis-tetrahydrofuranylurethane-containing nonpeptidic protease inhibitor (PI) UIC-94017 (TMC114) with potent activity against multi-PI-resistant human immunodeficiency virus in vitro

Abstract: We designed, synthesized, and identified UIC-94017 (TMC114), a novel nonpeptidic human immunodeficiency virus type 1 (HIV-1) protease inhibitor (PI) containing a 3(R),3a(S),6a(R)-bis-tetrahydrofuranylurethane (bis-THF) and a sulfonamide isostere which is extremely potent against laboratory HIV-1 strains and primary clinical isolates (50% inhibitory concentration [IC(50)], approximately 0.003 micro M; IC(90), approximately 0.009 micro M) with minimal cytotoxicity (50% cytotoxic concentration for CD4(+) MT-2 cells, 74 micro M). UIC-94017 blocked the infectivity and replication of each of HIV-1(NL4-3) variants exposed to and selected for resistance to saquinavir, indinavir, nelfinavir, or ritonavir at concentrations up to 5 micro M (IC(50)s, 0.003 to 0.029 micro M), although it was less active against HIV-1(NL4-3) variants selected for resistance to amprenavir (IC(50), 0.22 micro M). UIC-94017 was also potent against multi-PI-resistant clinical HIV-1 variants isolated from patients who had no response to existing antiviral regimens after having received a variety of antiviral agents. Structural analyses revealed that the close contact of UIC-94017 with the main chains of the protease active-site amino acids (Asp-29 and Asp-30) is important for its potency and wide spectrum of activity against multi-PI-resistant HIV-1 variants. Considering the favorable pharmacokinetics of UIC-94017 when administered with ritonavir, the present data warrant that UIC-94017 be further developed as a potential therapeutic agent for the treatment of primary and multi-PI-resistant HIV-1 infections.

The Still Face: A History of a Shared Experimental Paradigm

Abstract: When faced by a suddenly unresponsive social partner, young infants typically react by sobering and gazing away. This still-face reaction has intrigued researchers for several decades. In this article, we present a history of the still-face paradigm in which we locate early observations of the still-face effect, describe the formalization of a procedure that reliably produces it, and discuss how this procedure has been used to investigate a broad range of questions about early social and emotional development. In addition, we reflect on the heuristic value of shared experimental paradigms.

The comparative psychology of uncertainty monitoring and metacognition.

Abstract: Researchers have begun to explore animals' capacities for uncertainty monitoring and metacognition. This exploration could extend the study of animal self-awareness and establish the relationship of self-awareness to other-awareness. It could sharpen descrip- tions of metacognition in the human literature and suggest the earliest roots of metacognition in human development. We summarize research on uncertainty monitoring by humans, monkeys, and a dolphin within perceptual and metamemory tasks. We extend phyloge- netically the search for metacognitive capacities by considering studies that have tested less cognitively sophisticated species. By using the same uncertainty-monitoring paradigms across species, it should be possible to map the phylogenetic distribution of metacognition and illuminate the emergence of mind. We provide a unifying formal description of animals' performances and examine the optimality of their decisional strategies. Finally, we interpret animals' and humans' nearly identical performances psychologically. Low-level, stim- ulus-based accounts cannot explain the phenomena. The results suggest granting animals a higher-level decision-making process that in- volves criterion setting using controlled cognitive processes. This conclusion raises the difficult question of animal consciousness. The results show that animals have functional features of or parallels to human conscious cognition. Remaining questions are whether ani- mals also have the phenomenal features that are the feeling/knowing states of human conscious cognition, and whether the present par- adigms can be extended to demonstrate that they do. Thus, the comparative study of metacognition potentially grounds the systematic study of animal consciousness.

School social bonds, school climate, and school misbehavior: A multilevel analysis

Abstract: This research examines the extent to which individual- and school-level factors explain variation in school misbehavior among a nationally representative sample of high school students. The results reveal that higher levels of school attachment, school commitment, and belief in school rules are associated with lower levels of misbehavior in school, net of family and peer influences. With regard to school climate, larger schools in urban areas explain variations in school misbehavior. Overall, the results suggest that individual- and school-level covariates should be included in the study of school misbehavior.

Freaks, gold diggers, divas, and dykes: The sociohistorical development of adolescent African American women’s sexual scripts

Abstract: The development of a sexual self is based in an understanding of the messages and meanings an individual is given about sexual roles and behaviors. To understand how meanings become scripts unique to adolescent African American women’s experiences, it is important to look at how their images have been framed within a racialized and sexualized sociohistorical context. The remnants of the foundational Jezebel, Mammy, Matriarch, and Welfare. Mother images of African American womanhood remain today, as exemplified by similar, yet more sexually explicit scripts that include the Freak, Gold Digger, Diva, and Dyke. This paper explores the sociohistorical development of current sexual scripts for African American female adolescents through an interpretation of Hip Hop culture documents, and the available empirical research. The relevance of these current sexual scripts to sexual identity development, sexual risk-taking behaviors, and interpersonal relationship dynamics are also addressed.

State And Local E-Government: Prospects and Challenges

Abstract: This article presents a self-contained yet comprehensive discussion of the prospects of state and local electronic government (e-government), the status of its development across the states and local communities, and the difficult challenges faced in making it a reality. In taking a very broad approach to e-government, the hope is that the analysis helps to bring perspective to the issue and to synthesize a literature that is increasingly becoming a series of disconnected case studies. Although the prospects at all levels of government for improving public services, reducing costs, and enhancing the democratic process are high, e-government has been penetrating state government much more rapidly than local government. The most salient obstacles to full penetration of e-government seem to be proper marketing, privacy issues, equity, and financing.

The Hedonic Method

Abstract: Heterogeneous or differentiated goods are products whose characteristics vary in such a way that there are distinct product varieties even though the commodity is sold in one market (e.g., cars, computers, houses). The variation in product variety gives rise to variations in product prices within each market. The hedonic method for non-market valuation relies on market transactions for these differentiated goods to determine the value of key underlying characteristics. For instance, by observing the price differential between two product varieties that vary only by one characteristic (e.g., two identical cars, but with one having more horsepower than the other), we indirectly observe the monetary trade-offs individuals are willing to make with respect to the changes in this characteristic. As such, the hedonic method is an “indirect” valuation method in which we do not observe the value consumers have for the characteristic directly, but infer it from observable market transactions.

A Secure Base in Adolescence: Markers of Attachment Security in the Mother–Adolescent Relationship

Abstract: This study sought to identify ways in which adolescent attachment security, as assessed via the Adult Attachment Interview, is manifest in qualities of the secure base provided by the mother-adolescent relationship. Assessments included data coded from mother-adolescent interactions, test-based data, and adolescent self-reports obtained from an ethnically and socioeconomically diverse sample of moderately at-risk 9th and 10th graders. This study found several robust markers of adolescent attachment security in the mother-adolescent relationship. Each of these markers was found to contribute unique variance to explaining adolescent security, and in combination, they accounted for as much as 40% of the raw variance in adolescent security. These findings suggest that security is closely connected to the workings of the mother-adolescent relationship via a secure-base phenomenon, in which the teen can explore independence in thought and speech from the secure base of a maternal relationship characterized by maternal attunement to the adolescent and maternal supportiveness.

The Black Hole-Bulge Relationship in Quasars

Abstract: We use quasi-stellar object (QSO) emission-line widths to examine the MBH-σ* relationship as a function of redshift and to extend the relationship to larger masses. Supermassive black holes in galactic nuclei are closely related to the bulge of the host galaxy. The mass of the black hole MBH increases with the bulge luminosity and with the velocity dispersion of the bulge stars, σ*. An important clue to the origin of this correlation would be an observational determination of the evolution, if any, in the MBH-σ* relationship as a function of cosmic time. The high luminosity of QSOs affords the potential for studies at large redshifts. We derive black hole masses from the continuum luminosity and the width of the broad Hβ line and σ* from the width of the narrow [O III] lines. We find that radio-quiet QSOs conform to the established MBH-σ* relationship up to values of MBH ≈ 1010 M☉, with no discernible change in the relationship out to redshifts of z ≈ 3. These results are consistent with the idea that the growth of supermassive black holes and massive bulges occurred simultaneously.