bluuebunny/crossref_metadata_2025 huggingface dataset:
The Strategic Choice of Location and Transport Mode in a Successive Monopoly Model
Authors: Gupta Barnali , Heywood John S. , Pal Debashis
Published: March 2003

This work emphasizes the incentives for vertical integration in a spatial model. A downstream monopoly will both strategically increase its transport costs and locate inefficiently relative to its customers. This forces the upstream monopolist to lower its input price rather than permit sales to decline. The excess costs and the inefficient location lower total profit in the vertical stream generating an incentive for vertical integration.
Regional Specialization and Technical Leapfrogging
Authors: Amiti Mary
Published: March 2003

This paper investigates circumstances where a region loses its technological leadership after some major technological breakthrough. Input‐output linkages between firms in a Cournot upstream industry and a perfectly competitive downstream industry create forces for agglomeration in particular locations, driving up prices of immobile factors. A new technology that is incompatible with the old will not benefit from these linkages and so is more likely to be established in locations with little existing industry due to lower factor prices. Furthermore, in some circumstances the old and new technologies may coexist.
A General Misspecification Test for Spatial Regression Models: Dependence, Heterogeneity, and Nonlinearity
Authors: De Graaff Thomas , Florax Raymond J.C.M. , Nijkamp Peter , Reggiani Aura
Published: March 2003

There is an increasing awareness of the potentials of nonlinear modeling in regional science. This can be explained partly by the recognition of the limitations of conventional equilibrium models in complex situations, and also by the easy availability and accessibility of sophisticated computational techniques. Among the class of nonlinear models, dynamic variants based on, for example, chaos theory stand out as an interesting approach. However, the operational significance of such approaches is still rather limited and a rigorous statistical‐econometric treatment of nonlinear dynamic modeling experiments is lacking. Against this background this paper is concerned with a methodological and empirical analysis of a general misspecification test for spatial regression models that is expected to have power against nonlinearity, spatial dependence, and heteroskedasticity. The paper seeks to break new research ground by linking the classical diagnostic tools developed in spatial econometrics to a misspecification test derived directly from chaos theory—the BDS test, developed by Brock, Dechert, and Scheinkman (1987). A spatial variant of the BDS test is introduced and applied in the context of two examples of spatial process models, one of which is concerned with the spatial distribution of regional investments in The Netherlands, the other with spatial crime patterns in Columbus, Ohio.
Preferences for Housing, Jobs, and Commuting: A Mixed Logit Analysis
Authors: Rouwendal Jan , Meijer Erik
Published: March 2003

This paper reports stated preferences of Dutch workers for combinations of housing, employment, and commuting. The analysis uses standard logit models as well as mixed logit models. Estimation results offer insights into the relative importance of various aspects of housing, employment, and commuting. Households dislike commuting and the value of commuting time implied by the model is high in comparison to the wage rate. Nevertheless, preferences for some housing attributes are strong enough to make substantially longer commuting acceptable to most workers. Of special interest is the strong preference for living in small‐or medium‐size cities, especially among two income households. Using a mixed logit model instead of a standard logit model results in a substantial improvement of the loglikelihood, reflecting the importance of heterogeneity among respondents. If no individual characteristics are incorporated into the model, the mixed logit implies substantially lower average monetary evaluations of most attributes. These differences are much smaller if some individual characteristics are incorporated into the model.
First Language Influences on Second Language Word Reading: All Roads Lead to Rome
Authors: Wade‐Woolley Lesley
Published: March 2003

This article reports an experiment investigating similarities and differences in basic processing involved in the word reading of second language (L2) readers of English. The investigation specifically targeted phonological and orthographic processes in the context of language transfer from native language (L1) to L2 during reading tasks. Groups of young adults who were native speakers of either Russian or Japanese and low‐intermediate ESL learners were matched on a measure of English word reading and then compared on a number of cognitive and linguistic reading‐related tasks. Despite differences in processing strengths, neither group demonstrated an advantage in nonword reading. The results have implications for theories of reading disability built around the notion of deficits in phonological processing.
Individual Differences and the Fundamental Similarity of Implicit and Explicit Adult Second Language Learning
Authors: Robinson Peter
Published: March 2003

This study examines evidence for the claims of Krashen (1981, 1985) and Reber (1989, 1993; Reber, Walkenfield & Hernstadt, 1991) that unconscious learning under Implicit and Incidental conditions is insensitive to measures of individual differences in cognitive abilities, in contrast to learning under conscious Rule‐search and Instructed conditions. I assessed individual differences between 104 learners of English as a second language using two subtests of the Modern Language Aptitude Test (Carroll & Sapon, 1959). Following the participants' exposure to sentences illustrating easy and hard second language rules during training, I assessed their learning through a grammaticality judgment test. I assessed rule awareness on the basis of responses to a debriefing questionnaire which asked if learners had noticed rules, were looking for rules, and could verbalize the rules. Only in the Incidental condition was the extent of learning and awareness unrelated to individual differences in aptitude. Awareness at the level of Noticing did not accompany superior learning in any condition, but at the level of Looking for Rules, awareness accompanied superior learning for Implicit learners. At the level of Ability to Verbalize, awareness accompanied superior learning for both Implicit and Rule‐search learners.
What's the Subject of Study Abroad?: Race, Gender, and "Living Culture"
Authors: Talburt Susan , Stewart Melissa A.
Published: March 2003

Based on an ethnographic study that focused on the relations of students’ in‐ and out‐of‐class cultural learning during a 5‐week study abroad program in Spain, this article analyzes processes of teaching and learning in a Spanish culture and civilization class, the experiences of the only African‐American student on the program, and students’ responses to a class meeting in which race was overtly problematized. In contrast to the shared construction of cultural knowledge that characterized the class, discussion of race and gender was limited in its complexity, despite signs of new understandings among students. Given a need for all students to gain multiple cultural perspectives and growing evidence that peer groups constitute sources of identity and cross‐cultural understanding for students abroad, we suggest that study abroad curricula incorporate sustained discussion of students’ sociocultural differences and resulting particularities in their experiences in the host culture as part of the formal curriculum.
Teachers and Students, Students and Teachers: An Ever‐Evolving Partnership
Authors: Horwitz Elaine K.
Published: March 2003

This article provides a historical overview of Modern Language Journal (MLJ) articles that describe the teacher‐learner relationship. From the earliest issues of the MLJ, authors have noted the importance of recognizing and responding to individual learner differences. This review focuses on how language learners have been portrayed in the MLJ and the implications of these portrayals for language teaching. It, thus, addresses the characteristics that language learners have been seen to possess and how language teachers have been urged to respond to these characteristics. Specific topics include foreign language aptitude, motivation and other emotional responses to language learning, reasons for student attrition, and advice for modifying instruction for different learner‐types. This review also considers a number of articles written by language learners and addressed to their language teachers. Several recommendations are offered, including reinstitution of learner‐authored articles in the MLJ and closer attention to the learner's voice in reports of classroom‐based research.
The Relationship between Knowledge of Icraab, Lexical Knowledge, and Reading Comprehension of Nonnative Readers of Arabic
Authors: Khaldieh Salim A.
Published: March 2003

This article reports on an investigation into the role played by knowledge of both icraab and vocabulary in the reading comprehension of American learners of Arabic as a foreign language (AFL). Two groups (46 participants), proficient and less proficient, of nonnative readers of Arabic read an expository text, wrote an immediate recall protocol in their first language to measure their overall reading comprehension, and completed a vocabulary task and an icraab task. Whereas the analysis of the data revealed that vocabulary knowledge had a significant main effect, icraab was found not to have a significant role in reading comprehension. Although the issue of icraab needs further investigation, the results suggest that reading comprehension is independent of a knowledge of icraab and depends mainly on vocabulary knowledge.
The Geocoding of Synthetic Aperture Radar Imagery and an Application to Nautical Charting
Authors: Saundercock G.P.
Published: March 2003

An ERS‐1 SAR image of Frankfurt was geocoded using a variety of DEM spatial resolutions to examine the influence on positional accuracy compared with control points derived from a 1:50 000 scale map of the same area. It was demonstrated that mapping to 1:50 000 scale was possible in flat areas with a DEM resolution finer than 200 m.

The case for SAR imagery in nautical charting is discussed in the light of these results, drawing on recent experiences at the Hydrographic Office in charting the South Orkney Islands.
The Photogrammetric Society Analogue Instrument Project: a Fourth Extract
Authors: Burnside C. D.
Published: March 2003

The paper entitled The Photogrammetric Society Analogue Instrument Project was published in The Photogrammetric Record, 14(82): 565‐582 (October 1993) and contained, as Appendix A, an extract from the Archive concerned with the history of the Zeiss Stereoplanigraph in Great Britain. A further two extracts have since been published to provide details of direct optical projection instruments used in this country. This fourth extract now goes on to begin to provide some details of analogue plotters that employed a purely mechanical solution. The first instrument of this type to be described is the Vivian Thompson Stereo‐plotter of 1907. It was in fact the very first instrument of this important category ever to be produced but unfortunately it was also the only one produced in Great Britain.
Aerial Photography for Survey Purposes with a High Resolution, Small Format, Digital Camera
Authors: Mills J. P. , Newton I. , Graham R. W.
Published: March 2003

This paper discusses the work carried out to obtain stereoscopic “photography” from airborne platforms with a Kodak DCS200 digital camera, as part of an investigation into the suitability of current digital camera technology for use in air survey. Details of the work, from the initial test flight in a Cessna light aircraft through to tests utilizing a Thruster microlight platform, are documented. The paper concludes with a summary of the present shortcomings in obtaining aerial photography for survey purposes with still video technology and discusses the future prospects.
Surveying Stonehenge By Photogrammetry
Authors: Bryan P. G. , Clowes M.
Published: March 2003

For centuries the ruins of Stonehenge have proved to be both a source of fascination and mystery for the many visitors to this World Heritage Site. The monument itself sets a puzzle that even to this day has not been solved, although there have been numerous theories suggested as to its construction. There is little accurate survey data currently available on the stones themselves, against which these many theories could be tested. The Photogrammetric Unit of English Heritage was therefore requested, in 1993, to commence a project to digitally map all the external faces of all the stones that form the visible remains of this internationally important monument. Photogrammetry was the chosen survey technique and this paper outlines the work of the Unit in using the latest digital photogrammetric equipment to generate a basic three dimensional model of Stonehenge.
Mathematical Modelling and Accuracy Testing of Spot Level 1B Stereopairs
Authors: Valadan Zoej M. J. , Petrie G.
Published: March 2003

During a project concerned with DEM generation using SPOT stereoscopic imagery, difficulties were experienced when using Level 1B stereopairs for the task. This paper presents a mathematical solution to overcome this problem which has been implemented at the University of Glasgow. Results are included from experimental tests which were carried out over a test field in Jordan using this solution. These tests used five SPOT Level 1B stereopairs together with a single SPOT Level 1A stereopair for comparative purposes. The residual errors at the ground control points and independent check points are given and show that a satisfactory solution was achieved.
The Z/I Imaging Digital Camera System
Authors: Hinz A. , Heier H.
Published: March 2003

Market needs for airborne and spaceborne imagery used in photogrammetry and GIS applications are changing. Fundamental changes in sensors, platforms and applications are currently taking place. Most recently, new high resolution spaceborne sensors have become available. Besides classical photogrammetry, new thematic applications will drive the future image market. Savings in cost and time, together with the need for higher and reproducible radiometric resolution or spectral information will push forward the change from analogue to digital imagery. High resolution satellites will compete with airborne film‐based photography and digital camera systems.

With the availability of a digital airborne camera, it is possible to completely close the digital chain from image acquisition to exploitation and data distribution. The key decision regarding the camera design in this case is whether a linear or area array sensor should be used. In view of the high geometric accuracy requirements in photogrammetry, Z/I Imaging has focused development on a digital camera based on an area sensor. An essential aspect of this decision was not only the aerial camera system, but also the entire photogrammetric process to the finished photographic or mapping product. If this point of view is adopted, it becomes clear that the development of a digital camera involves more than simply exchanging film for silicon. Aspects such as data transfer rates, in‐flight data processing and storage, image archiving, georeferencing, colour fusion, calibration and preprocessing have the same influence on the economic assessment of a digital camera system. This paper describes current development activities and application aspects of a digital modular airborne camera system.
Budgeters' Views of State Performance‐Budgeting Systems: Distinctions across Branches
Authors: Melkers Julia E. , Willoughby Katherine G.
Published: March 2003

Given that a majority of states have had some sort of performance‐budgeting initiative on the books for several years, how has implementation of such reform progressed? To answer this question, we surveyed legislative and executive budgeters from the 50 states, asking them for their impressions of performance‐budgeting implementation in their state. Specifically, we asked these budget officers about the reasons for introducing performance budgeting in their state; the types of activities required of their system; responsible oversight bodies; extent of application across state agencies and departments; and perceived levels of effectiveness and problems experienced with implementation of the budget reform. Our findings indicate that implementation of performance‐based budgeting systems is proceeding slowly. While there are some benefits to highlight, results show that implementing performance budgeting is not without problems—perhaps the greatest being differing perceptions of use and success among budget players, particularly across branches of government.
Environmental Policy As Learning: A New View of an Old Landscape
Authors: Fiorino Daniel J.
Published: March 2003

Environmental policy in the United States has always been characterized by high levels of political conflict. At the same time, however, policy makers have shown a capacity to learn from their own and others' experience. This article examines U.S. environmental policy since 1970 as a learning process and, more specifically, as an effort to develop three kinds of capacities for policy learning. The first decade and a half may be seen in terms of technical learning, characterized by a high degree of technical and legal proficiency, but also narrow problem definitions, institutional fragmentation, and adversarial relations among actors. In the 1980s, growing recognition of deficiencies in technical learning led to a search for new goals, strategies, and policy instruments, in what may be termed conceptual learning . By the early 1990s, policy makers also recognized a need for a new set of capacities at social learning, reflecting trends in European environmental policy, international interest in the concept of sustainability, and dissatisfaction with the U.S. experience. Social learning stresses communication and interaction among actors. Most industrial nations, including the United States, are working to develop and integrate capacities for all three kinds of learning. Efforts to integrate capacities for conceptual and social learning in the United States have had mixed success, however, because the institutional and legal framework for environmental policy still is founded on technical learning.
Employer Liability for Employee Sexual Harassment: A Judicial Policy‐Making Study
Authors: Lee, Jr. Robert D. , Greenlaw Paul S.
Published: March 2003

Since 1964 and 1972 when Congress passed key legislation concerning sex discrimination, the courts have been left to fashion policies on sexual harassment in employment. In 1998, the Supreme Court issued four major decisions in this area, one dealing with suits against school districts, one involving same‐sex discrimination, and two pertaining to the application of common law to employer liability in sexual harassment cases. The ruling in the first case is at odds with the others, suggesting that Congress may need to intervene. The other three pose a series of complex issues that could benefit from congressional action and administrative guidance from the Equal Employment Opportunity Commission. The Court's rulings have answered some legal questions, but posed others that will produce extensive litigation in coming years.
Gendering the “Graying” of Society: A Discourse Analysis of the Care Gap
Authors: Outshoorn Joyce
Published: March 2003

This article analyzes to what extent the “care‐gap”—that is, too few carers looking after increasing numbers of the elderly—has become part of the problem definition of the demographic shift in the Netherlands in reports of the major scientific policy advisor to the government. Do these reports still assume a gender order in which women are informal carers and men are breadwinners? What notions about gender are circulating, and is the gender order challenged by policy recommendations? With a framework for gender‐discourse analysis, the author shows that, despite increasing awareness of the care gap, the problem definition remains framed as the costs of collective provision of health care and pensions. Recommendations still assume that women will continue to provide informal care while they also enter the labor market to maintain collective provisions.
Who Wants to Work for the Government?
Authors: Lewis Gregory B. , Frank Sue A.
Published: March 2003

In an era when everyone wants to be a millionaire, governments struggle to attract and retain highly qualified employees, making it more important than ever to understand what attracts people to the public service. Using contingency table analysis and logistic regression on the 1989 and 1998 General Social Surveys, we explore how individuals' demographic characteristics and the importance they place on various job qualities influence their preference for and employment in the public sector. Job security may still be the strongest attraction of government jobs, but high income and the opportunity to be useful to society also attract some Americans to the public service. Minorities, veterans, Democrats, and older Americans preferred public‐sector jobs more than whites, nonveterans, Republicans, and younger Americans, who were otherwise similar. Women and college graduates were more likely than comparable men and less‐educated respondents to have government jobs, but no more likely to prefer them. Overall, desire for government jobs declined markedly between 1989 and 1998.
A Test of the Racial Contact Hypothesis from a Natural Experiment: Baseball's All‐Star Voting as a Case
Authors: Hanssen F. Andrew
Published: March 2003

Objective. The contact hypothesis is difficult to test because of selectivity bias: the direction of causation between contact and attitudes cannot be definitively determined. Selectivity bias can be avoided given a sample for which, for reasons unrelated to group member attitudes, whites divide into groups that differ systematically in the amount of contact they have with blacks. This paper uses a natural experiment that provides such a test: All‐Star voting by baseball players versus fans. The average white player has more substantial and persistent contact with African Americans (as teammates) than does the average white fan, and the contact hypothesis would thus predict that players will discriminate less than fans, all else equal. Methods. Logistic, ordinary‐least‐squares (OLS), and tobit regressions are used to analyze the effect of candidate race on votes received, controlling for other factors. Results. No evidence is found of a differential in discrimination related to the amount of contact, although discrimination by both groups is found to decline between 1970 and 1980. Conclusion. The contact hypothesis is not supported; exogenous variations in the amount of interracial contact are not associated with difference in levels of discrimination.
Education and Public Attitudes toward Science: Implications for the “Deficit Model” of Education and Support for Science and Technology
Authors: Bak Hee‐Je
Published: March 2003

Objective. By critically examining the deficit model, this research attempts to grasp the multifaceted relationships between education and public attitudes toward science. Methods.It analyzes a series of nationwide surveys of public attitudes toward science conducted over a decade. Results. First, respondents' levels of education and levels of scientific knowledge make independent contributions to public attitudes toward science. Second, college (and postgraduate) majors have very weak effects on public attitudes toward science. Third, education is a much weaker predictor of public attitudes toward controversial scientific research, compared to its strong influence on science in general. Conclusions. Although education may indeed enhance public support for science in general, it may not help much to reduce tensions around politicized, controversial scientific research. For scientific controversies, gender might be a more important variable than education.
The Psychology of Dependence Between Landlord and Sharecropper in Northeastern Brazil
Authors: Johnson Allen
Published: March 2003

Contrasting beliefs and attitudes held by sharecroppers and their landlord on a fazenda in Northeastern Brazil reveal a tendency to split one another into positively and negatively idealized images. Sharecroppers who ambivalently seek patronage construct good vs. bad landlords/patrons. The landlord, defensive about envy and hostility among sharecroppers, constructs good vs. bad tenants/workers. Theory from the Kleinian school of psychoanalysis concerning envy, splitting, and idealization provides a framework for interpreting ethnographic case materials.
On the Varieties of National Attachment: Blind Versus Constructive Patriotism
Authors: Schatz Robert T. , Staub Ervin , Lavine Howard
Published: March 2003

Two studies explored a theoretical distinction between “blind” and “constructive” patriotism. Blind patriotism is defined as an attachment to country characterized by unquestioning positive evaluation, staunch allegiance, and intolerance of criticism. Constructive patriotism is defined as an attachment to country characterized by support for questioning and criticism of current group practices that are intended to result in positive change. Items designed to investigate these dimensions of national attachment were administered to two groups of undergraduates in separate surveys. Measures of the two constructs derived from factor analysis of the responses proved to be reliable and valid. Blind patriotism was positively associated with political disengagement, nationalism, perceptions of foreign threat, perceived importance of symbolic behaviors, and selective exposure to pro‐U.S. information. In contrast, constructive patriotism was positively associated with multiple indicators of political involvement, including political efficacy, interest, knowledge, and behavior. The implications of this distinction for theory and research on patriotism are discussed.
Pluralistic Ignorance and Political Correctness: The Case of Affirmative Action
Authors: Van Boven Leaf
Published: March 2003

The pressure to appear politically correct can have important consequences for social life. In particular, the desire to appear politically correct, and to avoid being seen as racist, sexist, or culturally insensitive, can lead people to espouse publicly support for politically correct issues, such as support for affirmative action, despite privately held doubts. Such discrepancies between public behavior and private attitudes, when accompanied by divergent attributions for one's own behavior and the identical behavior of others, can lead to pluralistic ignorance. Two studies investigated pluralistic ignorance with respect to affirmative action among undergraduates. Their survey responses indicate that people overestimate their peers' support for affirmative action and underestimate their peers' opposition to affirmative action, that people's ratings of the political correctness of supporting affirmative action are correlated with their overestimation of support for affirmative action, and that people view their own attitudes toward affirmative action as unique.
The Etiology of Individual‐Targeted Intolerance: Group Stereotypes and Judgments of Individual Group Members
Authors: Golebiowska Ewa A.
Published: March 2003

Virtually all scientific writing on attitudes toward political unorthodoxy in the United States focuses on group‐targeted tolerance, or the question of whether Americans are willing to extend constitutional rights and freedoms to groups outside the political mainstream. Less is known about the etiology of individual‐targeted tolerance, or the question of whether Americans are willing to tolerate the exercise of constitutional rights and freedoms by individuals who belong to unpopular groups. This paper examines the sources of attitudes toward individuals belonging to disliked and stereotyped political groups—in particular, the extent to which political tolerance judgments about gay and racist targets are influenced by attributes of those targets that are either consistent or inconsistent with group stereotypes. In line with expectations, an empirical analysis showed that individuals exhibiting attributes inconsistent with their group's stereotype (whether neutral with respect to stereotypic beliefs or directly challenging them) are tolerated more than those with stereotype‐consistent attributes. Because members of political outgroups can control the timing of disclosing their group membership, they have the power to determine whether and to what extent stereotypic beliefs associated with their group will influence the reactions they provoke. This analysis confirms that the impact of stereotypic beliefs on tolerance varies as a function of timing of group membership revelation, although the direction of this interaction depends on the intensity of dislike for the group of which the individual target is a member.
Psychocultural Interpretations and Dramas: Identity Dynamics in Ethnic Conflict
Authors: Ross Marc Howard
Published: March 2003

Ethnic identity connects individuals through perceived common past experiences and expectations of shared future ones. Identity is concerned with group judgments and judgments about groups and their motives. This article explores identity through the case of Loyal Order Protestant parades in Northern Ireland and the concepts of psychocultural interpretations (shared, deeply held worldviews found in group narratives) and psychocultural dramas (conflicts over competing, and apparently irresolvable, claims that engage the central elements of a group's historical experience). Psychocultural dramas are polarizing events whose manifest content involves non‐negotiable cultural claims, threats, and/or rights that become important because of their connections to core metaphors and group narratives that embody a group's identity. In ethnic conflicts, psychocultural dramas arise over competing claims that evoke deeply rooted dimensions of the conflict which cannot be settled by reference to more general rules or higher authority. Psychocultural dramas are tools of analysis for understanding the centrality of cultural identity and ritual in ethnic conflict and for the redefinition of such conflicts in ways that increase the chances for managing them constructively. Examining the psychocultural dramas surrounding parades disputes in Northern Ireland suggests why and how some conflicts are more amenable to constructive outcomes than others.
Managing natural resources in the light of climate variability
Authors: Lenton Roberto
Published: March 2003

Natural resource management is central to global efforts to reduce poverty and environmental degradation, and is one of the principal ways in which countries are seeking to advance sustainable development and the implementation of Agenda 21. But these efforts to advance natural resource management are strongly impacted by climate and by seasonal and inter–annual climate variability.

This article aims to further advance understanding of the relationship between natural resource management and climate variability, with particular attention to ways in which natural resource managers at every level — from the household to the national and international levels — can cope more effectively with such variability. In particular, the article provides an overview of the way in which efforts to manage natural resources to reduce poverty and environmental degradation are impacted by natural climate variability. It examines what natural resource managers are doing to cope with these challenges, and discusses the kinds of new approaches and partnerships that are needed to improve their capacity to cope more effectively with climate variability. In doing so, the article touches on the implications of future climate changes for natural resource managers and the way in which their efforts to cope more effectively with climate variability will provide opportunities to gain experience in identifying and adjusting responses to longer–term climate change.
Cryptosporidium Dose‐Response Studies: Variation Between Hosts
Authors: Teunis Peter F. M. , Chappell Cynthia L. , Okhuysen Pablo C.
Published: March 2003

The issue of variation is highly important in dose‐response analysis: variation among genetically related pathogens infecting the same host, but also variation among hosts, in susceptibility to infection by the same pathogen. This latter issue is addressed here for the protozoan parasite Cryptosporidium parvum, the causative agent for many outbreaks of water‐borne gastrointestinal illness. In human feeding studies, infectivity has been shown to be low in subjects with high preexisting anti‐Cryptosporidium IgG‐levels. Here we adapt the hit theory model of microbial infection to incorporate covariables, characterizing the immune status of the susceptible host. The probability of any single oocyst in the inoculum to cause infection appears to depend on preexisting IgG‐levels. This does not necessarily imply direct protection by the humoral immune system; high IgG‐levels may reflect a recent episode of infection/illness, and be an epi‐phenomenon associated with other protective responses. The IgG‐dependence of the dose‐response relation can be easily applied in quantitative risk analysis. The distribution of anti‐Cryptosporidium IgG levels in the general population is accessible by analyzing serum banks, which are maintained in many Western countries. Using such an approach provides first insights into the variation of susceptibility to infection in the general population.
Validating Benefit and Cost Estimates: The Case of Airbag Regulation
Authors: Thompson Kimberly M. , Segui‐Gomez Maria , Graham John D.
Published: March 2003

Preregulation estimates of benefits and costs are rarely validated after regulations are implemented. This article performs such a validation for the mandatory automobile airbag requirement. We found that the original 1984 model used to estimate benefits became invalid when 1997 values were input into that 1984 model. However, using a published 1997 cost‐effectiveness model, we demonstrate, by replacing the model inputs with the values from 1984, that the 1997 cost‐effectiveness ratios, based on real‐world crash data and tear‐down cost data, are less attractive than what would have been originally anticipated. The three most important errors in the 1984 input values are identified: the overestimation of airbag effectiveness, the overestimation of baseline fatality/injury rates, and the underestimation of manual safety belt use. This case study, which suggests that airbags are a reasonable investment in safety, shows that the regulatory analysis tools do not always produce findings that are biased against health, safety, and environmental regulation. Future validation studies of health, safety, and environmental regulation should focus on validation of benefit and risk estimates, areas where we found significant error, as well as on cost estimates.
Evaluating the Simplified Conjoint Expected Risk Model: Comparing the Use of Objective and Subjective Information
Authors: Carlstrom Lisa K. , Woodward J. Arthur , Palmer Christina G. S.
Published: March 2003

The simplified Conjoint Expected Risk (CER) model by Holtgrave and Weber posits that perceived risk is a linear combination of the subjective judgments of the probabilities of harm, benefit, and status quo, and the expected harm and benefit of an activity. It modifies Luce and Weber's original CER model—that uses objective information to evaluate financial gambles—to accommodate activities such as health/technology activities where values of the model variables are subjective. If the simplified model is a valid modification of the original model, its performance should not be sensitive to the use of subjective information. However, because people may evaluate information differently when objective information is provided to them than when they generate information on their own, the performance of the simplified CER model may not be robust to the source of model‐variable information. We compared the use of objective and subjective information, and results indicate that the estimates of the simplified CER model parameters and the proportion of variance in risk judgments accounted for by the model are similar under these two conditions. Thus, the simplified CER model is viable with activities for which harm and benefit information is subjective.
Do People Actually Pursue Risk Elimination in Environmental Risk Management?
Authors: Nakayachi Kazuya
Published: March 2003

This study examines whether people pursue the total elimination of environmental risks even if the risk reduction occurs incrementally and requires steadily increasing amounts of money to achieve. Participants' willingness to pay (WTP) was measured for various levels of reduction in the risk of cancer caused by dioxin. Results showed that: (1) people were willing to pay more for an initial reduction in risk than for subsequent reductions, (2) the WTP for the final risk decrement—which achieved total risk elimination—was higher than the WTP for either of the two previous decrements but barely half of that for the first reduction, and (3) the manner in which the questions were framed did not affect participants' responses. These results suggest that the public will not always try to pursue perfect safety at the cost of a large sum of money, but rather may seek a decreasing expenditure as the risk level is reduced.
From Breeder Reactors to Butterflies: Risk, Culture, and Biotechnology
Authors: Lomax Geoffrey P.
Published: March 2003

Social theories of risk suggest that a combination of scientific and cultural perspectives converge to influence risk perception. This article first surveys sociological perspectives suggesting that risks from modern technological development have become predominant concerns in the social consciousness. Particular attention is given to those theses describing how social elements work to create perception of risks in relation to new technologies. The themes that emerge from this survey are then related to comtemporary debates concerning biotechnology. Specific attention is given to recent controversies regarding genetically modified crops, and parallels are drawn between debates over nuclear power and biotechnology. A procedural ethic for public discourse and decision making over the diffusion of genetically modified foods is offered. Ethical and social theories are linked with the hope that by recognizing the social dimensions of debates over new technologies a broader framework for conducting risk analysis may emerge.
Radiocesium in Fish from the Savannah River and Steel Creek: Potential Food Chain Exposure to the Public
Authors: Burger Joanna , Gaines K. F. , Peles J. D. , Stephens Jr. W. L. , Boring C. Shane , Brisbin Jr. >I. L. , Snodgrass J. , Bryan, Jr. A. L. , Smith M. H. , Gochfeld M.
Published: March 2003

This study examined radiocesium (137Cs) levels in fish from the vicinity of the Department of Energy's Savannah River Site (SRS), a former nuclear weapons production facility in South Carolina. Fish from the Savannah River were sampled above (upstream), along, and below (downstream) the SRS, and from Steel Creek, a tributary that runs through the SRS. There was some off‐site contamination of 137Cs in the Savannah River watershed due to low‐level releases from past nuclear production on the SRS. The null hypotheses tested were that there would be no differences in 137Cs levels as a function of location along the river, and between species collected from the river and from Steel Creek on the SRS. For six of eight species of fish collected from the Savannah River, there were no differences in 137Cs levels in muscle from fish collected above, along, or below the SRS; exceptions were bowfin and shellcracker. Fish collected from Steel Creek had significantly higher levels (by about an order of magnitude) of 137Cs in muscle tissue than fish collected in the Savannah River. However, no fish from either Steel Creek or the Savannah River had 137Cs levels above the European Economic Community limit for fresh meat of 0.6 Bq/g. Lifetime cancer risk was calculated using the cancer slope factor of 3.2 × 10−11/pCi, and various fish consumption scenarios reflecting actual data from Savannah River fishermen. Using mean 137Cs concentrations and median fish consumption for 70 years for Black males—the group with the highest consumption—the excess lifetime risk associated with the eight species of fish in the Savannah River ranged from 9.0 × 10−7 to 1.0 × 10−5. The same calculation for fish from Steel Creek gave risk estimates from 1.4 to 8.0 × 10−5. The 95% level for consumption by Blacks, however, was about 70 kg/year. Black fishermen consuming that amount of bass from Steel Creek would sustain a lifetime risk of 3.1 × 10−4, whereas the same consumption of Savannah River bass would yield a risk estimate of 1.5 × 10−5.
Sensitivity Analysis, Monte Carlo Risk Analysis, and Bayesian Uncertainty Assessment
Authors: Greenland Sander
Published: March 2003

Standard statistical methods understate the uncertainty one should attach to effect estimates obtained from observational data. Among the methods used to address this problem are sensitivity analysis, Monte Carlo risk analysis (MCRA), and Bayesian uncertainty assessment. Estimates from MCRAs have been presented as if they were valid frequentist or Bayesian results, but examples show that they need not be either in actual applications. It is concluded that both sensitivity analyses and MCRA should begin with the same type of prior specification effort as Bayesian analysis.
Effects of Uncertainties on Exposure Estimates to Methylmercury: A Monte Carlo Analysis of Exposure Biomarkers versus Dietary Recall Estimation
Authors: Sanga Ravi N. , Bartell Scott M. , Ponce Rafael A. , Boischio Ana A. P. , Joiris Claude R. , Pierce Crispin H. , Faustman Elaine M.
Published: March 2003

This article presents a general model for estimating population heterogeneity and “lack of knowledge” uncertainty in methylmercury (MeHg) exposure assessments using two‐dimensional Monte Carlo analysis. Using data from fish‐consuming populations in Bangladesh, Brazil, Sweden, and the United Kingdom, predictive model estimates of dietary MeHg exposures were compared against those derived from biomarkers (i.e., [Hg]hair and [Hg]blood). By disaggregating parameter uncertainty into components (i.e., population heterogeneity, measurement error, recall error, and sampling error) estimates were obtained of the contribution of each component to the overall uncertainty. Steady‐state diet:hair and diet:blood MeHg exposure ratios were estimated for each population and were used to develop distributions useful for conducting biomarker‐based probabilistic assessments of MeHg exposure. The 5th and 95th percentile modeled MeHg exposure estimates around mean population exposure from each of the four study populations are presented to demonstrate lack of knowledge uncertainty about a best estimate for a true mean. Results from a U.K. study population showed that a predictive dietary model resulted in a 74% lower lack of knowledge uncertainty around a central mean estimate relative to a hair biomarker model, and also in a 31% lower lack of knowledge uncertainty around central mean estimate relative to a blood biomarker model. Similar results were obtained for the Brazil and Bangladesh populations. Such analyses, used here to evaluate alternative models of dietary MeHg exposure, can be used to refine exposure instruments, improve information used in site management and remediation decision making, and identify sources of uncertainty in risk estimates.
A Deliberative Method for Ranking Risks (I): Overview and Test Bed Development
Authors: Florig H. Keith , Morgan M. Granger , Morgan Kara M. , Jenni Karen E. , Fischhoff Baruch , Fischbeck Paul S. , DeKay Michael L.
Published: March 2003

Risk ranking offers a potentially powerful means for gathering public input to help set risk‐management priorities. In most rankings conducted to date, the categories and attributes used to describe the risks have varied widely, the materials and procedures have not been designed to facilitate comparisons among risks on all important attributes, and the validity and reproducibility of the resulting rankings have not been assessed. To address these needs, a risk‐ranking method was developed in which risk experts define and categorize the risks to be ranked, identify the relevant risk attributes, and characterize the risks in a set of standardized risk summary sheets, which are then used by lay or other groups in structured ranking exercises. To evaluate this method, a test bed involving 22 health and safety risks in a fictitious middle school was created. This article provides an overview of the risk‐ranking method and describes the challenges faced in designing the middle school test bed. A companion article in this issue reports on the validity of the ranking procedures and the level of agreement among risk managers regarding ranking of risks and attributes.
The Changing Property Tax in the West: State Centralization of Local Finances
Authors: Sokolow Alvin D.
Published: March 2003

Diminished local government autonomy and increased fiscal centralization in the hands of state government are the consequences of the restrictions on the local property tax imposed in the western states in the past twenty years. While the trend is a national one, it is more evident in the West than in other regions. Statewide voter initiatives account for some of the restrictions, particularly the more severe ones, but legislatures and governors also impose these limitations. In tracing the recent course of the centralization of local finance, this article details the property tax restrictions adopted in individual western states, examines the initiative and conventional legislative sources of these actions, and provides quantitative and qualitative evidence for the centralization thesis. In many western states the property tax has lost much of its local character, becoming in large part a fiscal and political tool for state policymakers.
State Item‐Veto Legal Issues in the 1990s
Authors: Lee Robert D.
Published: March 2003

During the 1990s, legal issues arising from governors exercising their item‐veto powers were prevalent. These issues arose despite the fact that in most instances, state constitutions grant these powers to governors. Also, legal issues were prevalent, even though these powers had been exercised for decades; one might have expected that most legal issues would have been resolved long before the 1990s. Topics in court included standing, advisory opinions, definitions of ’appropriation‘ and ’item,‘ reasons used by governors in exercising the veto power, post‐adjournment vetoes, and labor relations in conjunction with item‐vetoes that affect personnel. The item‐veto cases need to be considered in the broader context of state government, which encompasses such topics as initiatives and referenda, biennial budgeting, school desegregation mandates by courts, and balanced budget requirements. No single topic dominated litigation in the 1990s, but instead a breadth of topics was evident.