bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Cost of Adverse Selection in Individual Annuity Markets: Evidence From Singapore
Authors: Fong Wai Mun 
Published: March 2003

AbstractNew evidence is presented on the cost of adverse selection in individual annuity markets using Singapore data. The Singapore annuity market is an interesting setting to examine the cost of adverse selection for three reasons. First, unlike many Western countries, the Singapore government provides very limited public financial assistance for retirees. Second, while social security contributions mandated under the Central Provident Fund (CPF) result in a high forced savings rate, a large proportion of CPF savings, are used up for housing. Third, to ensure that retirees have sufficient funds to meet basic needs, individuals who reach age 55 are required to set aside a minimum amount of their CPF savings, which can be withdrawn at age 62. The CPF Board allows various options for investing the minimum sum, but the most attractive option is to purchase an annuity. The institutional setting in Singapore in effect provides insurers with a large captive market for annuities. It is conjectured that this should be reflected in a significantly lower cost of adverse selection for annuities sold in Singapore as compared with other countries. The results herein, using data for CPF‐approved insurers, are strongly consistent with this conjecture. On average, money's worth of annuities is higher than annuities sold to a similar age‐gender mix in the United States, United Kingdom, and Australia. Adverse selection accounts for less than 13 percent of the cost of longevity insurance compared to 30–50 per‐ cent documented in many previous studies. These results suggest that one way to resolve the adverse selection problem is to adopt a universal individual defined contribution pension scheme that mandates or provides strong incentives for retirees to purchase annuities.
Adverse Selection and the Capped Premium Subsidy in the Federal Employees Health Benefits Program
Authors: Gray Bradley M. , Selden Thomas M. 
Published: March 2003

AbstractThis article examines the relationship between adverse selection and the capped premium subsidy in the Federal Employees Health Benefit Program (FEHBP). Understanding this relationship is important, not only because the FEHBP is the largest employer‐sponsored health program in the United States, but also because it has been proposed as a market‐based model for the reform of both Medicare and the market for nongroup private coverage. We present a theoretical model of the FEHBP that we then test using enrollee data. In particular, we exploit the natural experiment that arises from variation in the premium subsidy cap across Metropolitan Statistical Areas (MSAs). Although the nominalsubsidy cap is constant across MSAs, its real value varies greatly across MSAs with different price levels. The empirical analysis herein supports the contention that the premium subsidy in the FEHBP helps reduce adverse selection.
A Comparison of State‐of‐the‐Art Classification Techniques for Expert Automobile Insurance Claim Fraud Detection
Authors: Viaene Stijn , Derrig Richard A. , Baesens Bart , Dedene Guido 
Published: March 2003

AbstractSeveral state‐of‐the‐art binary classification techniques are experimentally evaluated in the context of expert automobile insurance claim fraud detection. The predictive power of logistic regression, C4.5 decision tree,k‐nearest neighbor, Bayesian learning multilayer perceptron neural network, least‐squares support vector machine, naive Bayes, and tree‐augmented naive Bayes classification is contrasted. For most of these algorithm types, we report on several operationalizations using alternative hyperparameter or design choices. We compare these in terms of mean percentage correctly classified (PCC) and mean area under the receiver operating characteristic (AUROC) curve using a stratified, blocked, ten‐fold cross‐validation experiment. We also contrast algorithm type performance visually by means of the convex hull of the receiver operating characteristic (ROC) curves associated with the alternative operationalizations per algorithm type. The study is based on a data set of 1,399 personal injury protection claims from 1993 accidents collected by the Automobile Insurers Bureau of Massachusetts. To stay as close to real‐life operating conditions as possible, we consider only predictors that are known relatively early in the life of a claim. Furthermore, based on the qualification of each available claim by both a verbal expert assessment of suspicion of fraud and a ten‐point‐scale expert suspicion score, we can compare classification for different target/class encoding schemes. Finally, we also investigate the added value of systematically collecting nonflag predictors for suspicion of fraud modeling purposes. From the observed results, we may state that: (1) independent of the target encoding scheme and the algorithm type, the inclusion of nonflag predictors allows us to significantly boost predictive performance; (2) for all the evaluated scenarios, the performance difference in terms of mean PCC and mean AUROC between many algorithm type operationalizations turns out to be rather small; visual comparison of the algorithm type ROC curve convex hulls also shows limited difference in performance over the range of operating conditions; (3) relatively simple and efficient techniques such as linear logistic regression and linear kernel least‐squares support vector machine classification show excellent overall predictive capabilities, and (smoothed) naive Bayes also performs well; and (4) the C4.5 decision tree operationalization results are rather disappointing; none of the tree operationalizations are capable of attaining mean AUROC performance in line with the best. Visual inspection of the evaluated scenarios reveals that the C4.5 algorithm type ROC curve convex hull is often dominated in large part by most of the other algorithm type hulls.
Firm Size and Growth in the United Kingdom Life Insurance Industry
Authors: Hardwick Philip , Adams Mike 
Published: March 2003

AbstractThis study tests whether the organic growth rates of United Kingdom (UK) life insurance firms are independent of size, as predicted by Gibrat's (1931) Law of Proportionate Effects. Using data for 1987–1996 and the three subperiods, 1987–1990, 1990–1993, and 1993–1996, we find that smaller life insurance firms tended to grow faster than larger ones in the 1987–1990 period and that larger life insurers tended to grow faster than smaller ones in the 1990–1993 and 1993–1996 periods. But over the ten‐year period, we find no significant difference between the growth rates of small and large firms, thus supporting Gibrat's Law as a long‐run tendency in the UK life insurance industry. When we examine firm‐specific determinants of asset growth, we find evidence in 1987–1996 and 1987–1990 that more diversified life insurance firms experienced higher growth rates on average than more specialized life insurers. We also find that the growth of life insurance firms was related to input costs during the 1990–1993 and 1993–1996 subperiods.
Flexible Spending Accounts as Insurance
Authors: Cardon James H. , Showalter Mark H. 
Published: March 2003

AbstractWe model flexible spending accounts (FSAs) as a special type of insurance policy. We prove the following results given losses drawn from a continuous distribution: (1) the optimal election amount, F*, is increasing in the consumer's level of risk aversion; (2) F* is increasing in the level of the maximum loss; If utility is decreasing in absolute risk aversion (DARA), then F* is (3) decreasing in income and (4) increasing in the marginal tax rate.
The Impact of Communication Strategy on Launching New Products: The Moderating Role of Product Innovativeness
Authors: Lee Yikuan , Colarelli O'Connor Gina 
Published: March 2003

Academic literature is filled with debate on whether product innovativeness positively impacts new product performance (NPP) because of increasing competitive advantage or negatively impacts performance due to consumers' fears of novel technology and resultant resistance to adopt. This study investigates this issue by modeling product innovativeness as a moderator that influences the relationship between communication strategy and new product performance. The authors emphasize that the impact of innovativeness to producers is different from that to consumers and that the differences have strategic impact when commercializing highly innovative products. Product innovativeness is conceptualized as multidimensional, and each dimension is tested separately. Four dimensions of innovativeness are explored—product newness to the firm, market newness to the firm, product superiority to the customer, and adoption difficulty for the customer.In this study, communication strategy is comprised of preannouncement strategy and advertising strategy. First, the relationship between whether or not a preannouncement is offered and NPP is explored. Then three types of preannouncement messages (customer education, anticipation creation, and market preemption) are investigated. Advertising strategy is characterized by whether the advertisement campaign at the time of launch was based primarily on emotional or functional appeals.Using empirical results from 284 surveys of product managers, the authors find that the relationship between communication strategy and NPP is moderated by innovativeness, and that the relationships differ not only by degree but also by type of innovativeness. Implications for research and practice are discussed.
Do Banks Provide Financial Slack?
Authors: Hadlock Charles J. , James Christopher M. 
Published: March 2003

ABSTRACTWe study the decision to choose bank debt rather than public securities in a firm's marginal financing choice. Using a sample of 500 firms over the 1980 to 1993 time period, we find that firms are relatively more likely to choose bank loans when variables that measure asymmetric information problems are elevated. The sensitivity of the likelihood of choosing bank debt to information problems is greater for firms with no public debt outstanding. These results are consistent with the hypothesis that banks help alleviate asymmetric information problems and that firms weigh these information benefits against a wide range of contracting costs when choosing bank financing.
Tactile sensory function in the forearm of the monotreme Tachyglossus aculeatus
Authors: Mahns David A. , Coleman Gordon T. , Ashwell Ken W.S. , Rowe Mark J. 
Published: March 2003

AbstractPeripheral tactile neural mechanisms in the forepaw of the echidna (Tachyglossus aculeatus, from the order Monotremata) were investigated to establish the extent of correspondence or divergence that has emerged over the widely different evolutionary paths taken by monotreme and placental mammals. Electrophysiological recordings were made in anesthetized echidnas from 29 single tactile sensory nerve fibers isolated in fine strands of the median or ulnar nerves of the forearm. Controlled tactile stimuli were applied to the forepaw glabrous skin to classify fibers, initially, into two broad divisions, according to their responses to static skin displacement. One displayed slowly adapting (SA) response properties, and the other showed a selective sensitivity to the dynamic components of the skin displacement. The SA class was made up of low‐threshold SA fibers and other less sensitive SA fibers, and the purely dynamically sensitive tactile fibers could be subdivided according to vibrotactile sensitivity and receptive field characteristics into a rapidly adapting (RA) class, sensitive to low‐frequency (≤50‐Hz) vibration, that resembled a corresponding RA class in placental species, and another class, sensitive to a broader range of vibrotactile frequencies (∼50–300 Hz), that may represent a monotreme equivalent of the Pacinian corpuscle (PC)‐related fiber class of placental mammals. The differential tactile sensitivity of the three principal fiber classes and their individual coding characteristics, determined by quantitative stimulus‐response analysis, indicate, first, that this triad of fiber classes can subserve high‐acuity tactile signalling from the echidna footpad and, second, that peripheral tactile sensory mechanisms are highly conserved across evolutionarily divergent mammalian orders. J. Comp. Neurol. 459:173–185, 2003. © 2003 Wiley‐Liss, Inc.
A statistical method for judging synergism: application to an endocrine disruptor animal experiment
Authors: Matsunaga Nobuhito , Kanno Jun , Yoshimura Isao 
Published: March 2003

AbstractThis article proposes a statistical method for judging whether or not the combined action of chemicals is synergistic, being focused on the case in which two or more endocrine disruptors are made to act simultaneously. After defining synergism, the synergistic relation of two chemicals is formulated for a higher response than that expected under an exchangeable relation between them. Using this formulation as a basis, we then rationalize the triangular design for an animal experiment in which all dose settings are controlled within a triangle domain that prescribes the sum of doses of simultaneously applied chemicals less than a certain level. In addition, a statistical test is proposed for judging the synergism among chemicals used in animal experiments, i.e. the test evaluates the discrepancy between the observed mean response from simultaneous administration groups of chemicals and an estimated response under the null hypothesis of zero interaction based on data from single administration groups. Finally, test performance is examined using a simulation study and a case study—the rodent uterotrophic assay. The simulation study revealed that the test is not superior in power to the standard analysis of variance test based on a linear model with interaction term, yet robust in the sense that type I errors under variance heterogeneity were better controlled using Welch correction than the analysis of variance test. The application of the proposed statistical test to an animal experiment is considered acceptable based on results. Copyright © 2003 John Wiley & Sons, Ltd.
HLA‐A, ‐B, ‐C polymorphism in a UK Ashkenazi Jewish potential bone marrow donor population
Authors: Cox S.T. , Marsh S.G.E. , Scott I. , Clayton J. , Argüello J.R. , McWhinnie A.J. , Prokupek B. , Holman R. , Madrigal J.A. , Little A.‐M. 
Published: March 2003

Abstract:To further our knowledge of HLA polymorphism in different ethnic populations and to increase the number of full HLA class I typed potential bone marrow donors on the Anthony Nolan Bone Marrow Trust register, HLA‐A, ‐B and ‐C polymorphism was characterised in 412 Ashkenazi Jewish potential donors. Serological typings and limited molecular analysis was performed for HLA‐A and ‐B, and molecular typings were performed for HLA‐C. Gene and haplotype frequencies were calculated using the maximum likelihood method and compared with UK Caucasoid and other Jewish populations. While the specificities identified were in general overlapping with the UK Caucasoid data, a difference in the frequencies of individual specificities was observed. For example, HLA‐B62, a common serotype found in the UK Caucasoid population, is almost absent in the Ashkenazim. HLA‐A, ‐C, ‐B haplotype frequencies also differ between the two populations with A26‐Cw*1203‐B38 and A24‐Cw*04‐B35 significant in the Ashkenazim, whilst A1‐Cw*07‐B8, a common Caucasoid haplotype, was found to be less frequent. Overall the results for the UK Ashkenazi population were most similar to previous reports on Polish/Russian Jews.
Genetic polymorphisms at the tumour necrosis factor loci (TNFA and TNFB) in cardiac sarcoidosis
Authors: Takashige N. , Naruse T.K. , Matsumori A. , Hara M. , Nagai S. , Morimoto S. , Hiramitsu S. , Sasayama S. , Inoko H. 
Published: March 2003

Abstract:Many studies have previously confirmed high TNFα (tumor necrosis factor‐alpha) production in sarcoidosis, and have shown that TNFα plays an important role in granuloma formation. We investigated TNFA and TNFB (lymphotoxin‐alpha) gene polymorphisms in 26 cardiac sarcoidosis patients of Japanese origin. These studies revealed a significant increase in the more uncommon TNFA2 allele in the patient group, suggesting that the TNFA gene controls the genetic susceptibility to cardiac sarcoidosis.
Nucleotide sequence of a new HLA‐DQB1 allele, DQB1*03033
Authors: Schranz P. , Renz M. , Seelig R. , Seelig H.P. 
Published: March 2003

Abstract:HLA‐genotyping by sequencing of the corresponding polymerase chain reaction (PCR) product allow the identification of a new HLA‐DQB1 allele, DQB1*03033. To confirm the finding the entire exon 2 was sequenced Note.
A unique second donor splice site in the intron 5 sequence of the HLA‐A*11 alleles results in a class I transcript encoding a molecule with an elongated cytoplasmic domain
Authors: Tijssen H.J. , Sistermans E.A. , Joosten I. 
Published: March 2003

Abstract:Full‐length cDNA sequencing of the A*1103 allele revealed an insertion of 18 bp between exon 5 and 6. We hypothesized that this could be the result of alternative splicing. Sequencing of intron‐5 of A*1101, *1102 and *1103 alleles demonstrated that this 18‐bp insertion consisted of the 5′‐end of intron 5, concluded by a second in‐frame donor splice site. Alignment of the 5′‐end intron 5 sequence of A*1101–3 with that of A*0101, *0201 and 0301 revealed a unique polymorphism at position 17 of the intron (A to G) that created this second donor splice site. To exclude the possibility of an Epstein‐Barr virus (EBV)‐induced event, reverse transcriptase‐polymerase chain reaction (RT‐PCR) analysis was performed on both peripheral blood mononuclear cells (PBMC) and EBV‐transformed b‐LcL’s of several A*11‐positive individuals, using primers spanning exons 5 and 6. Without exception, both cell types revealed two products for A*11. Densitometric analysis using EBV‐transformed b‐LcL’s and PBMC indicated a ratio of approximately 4:1 in favor of the alternative splice product. Notably, except for the A*11’s none of the other A‐locus alleles yields this alternative splice product. Translation of this product will result in a protein that has an additional 6 amino acids in its cytoplasmic domain. This introduces a negative charge just behind the basic anchor residues of the cytoplasmic segment and results in the loss of the single potential protein kinase C phosphorylation site ( Note).
HLA‐DRB1 and DQB1 genotypes in patients with insulin‐dependent neonatal diabetes mellitus. A study of 13 cases
Authors: Marquis E. , Le Monnier de Gouville I. , Bouvattier C. , Robert J.J. , Junien C. , Charron D. , Hors J. , Diatloff‐Zito C. 
Published: March 2003

Abstract:Insulin‐dependent neonatal diabetes mellitus (NDM) is a rare form of diabetes with a heterogeneous genetic background. The HLA‐DRB1 and DQB1 genotypes were determined for 13 patients with NDM, from 9 unrelated families. Four patients had permanent NDM (PNDM) and 9 patients had transient NDM (TNDM). No excess of HLA susceptibility markers for type 1 diabetes (IDDM) was observed in this series of patients, whatever the forms of diabetes PNDM or TNDM. Paternal isodisomy of chromosome 6 was observed in two TNDM cases. These observations are consistent with the current hypothesis that there is a recessive susceptibility gene, at least in the transient form of the disease, unlinked to the MHC locus on chromosome 6. Although established in a short series, our results do not support an additive role of IDDM1 in the progression of the disease.
CDw149 antibodies recognize a clustered subset of CD47 molecules associated with cytoplasmic signaling molecules
Authors: Drbal K. , Černý J. , Angelisová P. , Hilgert I. , Cebecauer M. , Šinkora J. , Hořejší V. 
Published: March 2003

Abstract:One of the recently described antigens broadly expressed on human leukocytes is CDw149, which was defined at the 6th Human Leukocyte Differentiation Antigen (HLDA) Workshop by means of 2 monoclonal antibodies (mAbs). Molecular characterization of this antigen has been lacking. In the present study we demonstrate that these anti‐CDw149 mAbs actually recognize a clustered subset of a well‐defined membrane protein, CD47, also known as integrin‐associated protein (IAP). This clustered subset is present on leukocytes but not erythrocytes. The anti‐CDw149 mAbs bind with only low affinity to a monomeric (unclustered) subset of CD47 but with high avidity to the CD47 clusters. A fraction of CD47 is associated with large complexes containing cytoplasmic signaling molecules (Src family kinases and heterotrimeric G‐proteins) similar to glycosphingolipid‐enriched microdomains (GEMs), which may explain the previously described signaling capacity of CD47. The low‐affinity anti‐CD47 mAbs may be useful tools targeting specific receptor complexes involved in cell activation. Specific reactivity of low‐affinity mAbs with clustered subsets of cell surface antigens may more generally explain the nature of poorly defined “activation forms” or activation neoepitopes described previously for several cell surface molecules.
A point mutation in β2‐microglobulin results in loss of epitope expression
Authors: Dimaano C. , Nguyen T. , Ahmed A. , Abel E. , Schultz C.S. , Nieto M.C. 
Published: March 2003

Acknowledgments:This work was supported by a National Institutes of Health‐Minority Biomedical Research Support (MBRS) grant (S06 GM48135).Abstract:A common tool in studying the structure and function of major histocompatibility complex: (MHC) class I is the generation and analysis of β2‐microglobulin (β2m) mutations. β2m has been shown to affect proper class I antigen presentation at the level of structural functionality. Many studies characterizing β2m function in class I presentation have used antibody‐based assays. Monitoring the effect of β2m mutation on antibody epitope expression, therefore, is essential in being able to truly characterize the impact of a mutant interaction between β2m and class I. Here we describe a mutant β2m molecule, β2m #32, that in association with class I loses reactivity with the human β2m‐specific monoclonal antibody, BBM.1. However, the BBM.1 epitope remains intact when β2m #32 is free from class I association.
MICA 5.1 allele is a susceptibility marker for psoriasis in the Korean population
Authors: Choi H.B. , Han H. , Youn J.I. , Kim T.Y. , Kim T.G. 
Published: March 2003

Abstract:In order to investigate the possibility that the MICA gene is involved in the pathogenesis of psoriasis, microsatellite polymorphism in the transmembrane region of MICA was studied in 138 Korean patients with psoriasis and compared with 126 healthy controls. The MICA 5.1 microsatellite allele, consisting of 5.1 repetitions of GCT/AGC, showed significantly higher frequencies in all patients and in patients with type I psoriasis than in the controls. HLA‐A30‐B13‐Cw*0602‐MICA 5.1 and A1‐B37‐Cw*0602‐MICA 5.1 were found to be an extended haplotype associated with psoriasis. Our results suggest that the MICA 5.1 allele might be a genetic marker related to the early onset of psoriasis and play a secondary role to the HLA‐Cw*0602 gene or an unknown causative gene closely linked to HLA‐Cw*0602 in the genetic susceptibility to psoriasis.