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171.
Partisan bias refers to an asymmetry in the way party vote share is translated into seats, i.e., a situation where some parties are able to win a given share of seats with a lesser (share of the) vote than is true for other parties. Any districted system is potentially subject to partisan biases. We show that there are three potential sources of partisan bias: (1) differences in the nature of the vote shares of the winning candidates of different parties that give rise to differences in the proportion of each party's votes that come to be ‘wasted’—differences which arise because of the nature of the geographic distribution of partisan support; (2) turnout rate differences across districts that are linked to the partisan vote shares in those districts, such that certain parties are more likely to have ‘cheap seats’ vis-à-vis turnout; and (3) malapportionment. In the context of two-party competition over single-member districts we provide a simple formulation to calculate the independent effect of each of these three factors. We illustrate our analysis with a calculation of the magnitude and direction of effects of the three determinants of partisan bias in elections to the US House and the US Senate in 1984, 1986 and 1988; then we consider how to extend the approach to a system with a mix of single- and multi-member districts or to a weighted voting system such as the US electoral college. We then apply the method to calculate the nature and sources of partisan bias in the 1984 and 1988 US presidential elections. 相似文献
172.
173.
The pattern of state support for Prohibition (18th Amendment, 1919) and Repeal (21st Amendment, 1933) is analyzed and compared. This comparison is important because Prohibition is the only amendment ever to be repealed. The main thesis is that there was no wholesale change in preferences of citizens. Instead, producer interests failed to mobilize effectively in 1919, and the coupling of moral and economic arguments that worked in 1919 broke apart in 1933. Regression analysis is conducted on state legislatures (for Prohibition) and state referenda on convention delegates (for Repeal), so states are observations in the cross-sectional regression analysis. The results broadly support the main thesis. 相似文献
174.
This paper evaluates the role that partisan politics plays in altering public spending levels. The analysis covers over three decades of data on the developments of the public sectors in 16 OECD countries. The results of the analysis lend firm support to the partisan politics model. Of special note is the distinction between the electorate' and the government' ideological preferences and the dominant role that the former plays. The results also suggest, contrary to conventional wisdom, that partisan political influences have not been eliminated with the tightening of linkages to the international economy. 相似文献
175.
176.
Lewis RJ Huffine EF Chaturvedi AK Canfield DV Mattson J 《Journal of forensic sciences》2000,45(4):898-901
During fatal aviation accident investigations, biosamples from the victims are submitted to the FAA Civil Aeromedical Institute (CAMI) for drug analysis. In the process of one such analysis by CAMI, an unknown substance was found in a urine sample. Simultaneous screening by thin layer chromatography (TLC) and gas chromatography/FID (GC/FID) suggested the presence of pseudoephedrine. A subsequent routine confirmation analysis of a separate urine aliquot by GC Fourier transform infrared (GC/FTIR) and GC mass spectrometry (GC/MS) indicated that the retention times of the unknown substance matched with those of pseudoephedrine. However, its infrared and mass spectra were different--the -OH and -NH groups were missing, a C-O-C group was present, and the molar mass was 12 atomic mass units (amu) more than that of pseudoephedrine. A subsequent literature search suggested that ephedrine-like amines react with aldehydes to form oxazolidines. Therefore, the 12-amu increase could be accounted for by condensation of pseudoephedrine with formaldehyde. Since this aldehyde is present in various grades of methanol and ethyl acetate, and these solvents were used during the solid-phase extraction, 3,4-dimethyl-5-phenyl-1,3-oxazolidine was synthesized by using (+)-pseudoephedrine HCl and formaldehyde. The analytical findings of the synthesized compound were consistent with those of the unknown interfering substance, confirming that it was the oxazolidine. Aldehyde contaminants in solvents or specimens can transform drugs of interest and may result in misidentification of a compound originally present in specimens. Therefore, chemicals used in analyses should be of the highest available purity, and a multi-analytical approach should be adopted to maintain a high degree of quality assurance. 相似文献
177.
Morphine-3-D glucuronide stability in postmortem specimens exposed to bacterial enzymatic hydrolysis
Carroll FT Marraccini JV Lewis S Wright W 《The American journal of forensic medicine and pathology》2000,21(4):323-329
Medical examiners frequently rely on the finding of free morphine present in postmortem specimens to assist in certifying deaths associated with narcotics. In vitro hydrolysis of morphine-3-D glucuronide (M3DG) to free morphine was studied using variable specimen pH, initial degree of specimen putrefaction, storage temperature and time, and the effectiveness of sodium fluoride (NaF) preservation. Reagent M3DG was added to opiate-free fresh blood and urine and to autopsy-derived blood specimens. Reagent bovine glucuronidase was also added to certain specimens. Freshly collected and refrigerated NaF-preserved blood produced minimal free morphine, whereas four of five autopsy blood specimens produced free morphine from M3DG. Increased storage time, temperature, and initial degree of putrefaction resulted in greater free morphine generation despite the absence of viable bacteria. Hydrolysis occurring during specimen storage can generate free morphine from M3DG and may result in erroneous conclusions in certifying narcotic deaths. 相似文献
178.
Steadman HJ Silver E Monahan J Appelbaum PS Robbins PC Mulvey EP Grisso T Roth LH Banks S 《Law and human behavior》2000,24(1):83-100
Since the 1970s, a wide body of research has suggested that the accuracy of clinical risk assessments of violence might be increased if clinicians used actuarial tools. Despite considerable progress in recent years in the development of such tools for violence risk assessment, they remain primarily research instruments, largely ignored in daily clinical practice. We argue that because most existing actuarial tools are based on a main effects regression approach, they do not adequately reflect the contingent nature of the clinical assessment processes. To enhance the use of actuarial violence risk assessment tools, we propose a classification tree rather than a main effects regression approach. In addition, we suggest that by employing two decision thresholds for identifying high- and low-risk cases--instead of the standard single threshold--the use of actuarial tools to make dichotomous risk classification decisions may be further enhanced. These claims are supported with empirical data from the MacArthur Violence Risk Assessment Study. 相似文献
179.
Thomas J. Cottle 《Journal of youth and adolescence》1973,2(3):201-212
A study of the recollections of childhood of a 12-year-old girl is placed in the context of developmental perceptions of time. Specifically, the transition from wishful to more realistic perceptions of the future is discussed, along with the growing capacity of the older child to incorporate experiences of the past into the present. The role of time perception in the formation of identity is presented from the perspective of psychological maturation and the growing comprehension of social roles and personal competence.In order to preserve confidentiality, I have used a fictitious name for a real family. In addition, the family has granted permission to publish this paper.Received B. A. from Harvard University and M.A. and Ph.D. from the University of Chicago in the Department of Sociology. Interests lie in the areas of social theory, poverty, psychotherapy, youth and adolescence, and perceptions of time. 相似文献
180.
The purpose of this study was to examine conflict in the home environment of adolescents from divorced families across a 3-year period. Adolescents from intact (106) and mother-custody divorced (60) families participated. Interparental conflict and parent-adolescent relations were assessed. Results indicated that adolescents from divorced families did not experience more conflictual home environments than those from intact families. In fact, interparental relations after the first year and parent-adolescent relations in general appeared to be less conflictual in divorced families. Limitations and implications of the findings are discussed. 相似文献