Classification of premium and regular gasoline by gas chromatography/mass spectrometry,principal component analysis and artificial neural networks

Detection and correct classification of gasoline is important for both arson and fuel spill investigation. Principal component analysis (PCA) was used to classify premium and regular gasolines from gas chromatography-mass spectrometry (GC-MS) spectral data obtained from gasoline sold in Canada over one calendar year. Depending upon the dataset used for training and tests, around 80-93% of the samples were correctly classified as either premium or regular gasoline using the Mahalanobis distances calculated from the principal components scores. Only 48-62% of the samples were correctly classified when the premium and regular gasoline samples were divided further into their winter/summer sub-groups. Artificial neural networks (ANNs) were trained to recognise premium and regular gasolines from the same GC-MS data. The best-performing ANN correctly identified all samples as either a premium or regular grade. Approximately 97% of the premium and regular samples were correctly classified according to their winter or summer sub-group.     

Modeling SSI financial eligibility and simulating the effect of policy options

This article simulates eligibility for Supplemental Security Income (SSI) among the elderly, analyzes factors affecting participation, and looks at the potential effects of various options to modify financial eligibility standards for the federal SSI program. We find that in the estimated noninstitutional elderly population of 30.2 million in the United States in 1991, approximately 2 million individuals aged 65 or older were eligible for SSI (a 6.6 percent rate of eligibility). Our overall estimate of the rate of participation among eligible elderly is approximately 63 percent, suggesting that more than a third of those who are eligible do not participate in the program. The results of our analysis of factors affecting participation among the eligible elderly show that expected SSI benefits and a number of demographic and socioeconomic variables are associated with the probability of participation. We also simulate the effects of various policy options on the poverty rate, poverty gap, annual program cost, the number of participants, and the average estimated benefits among participants. The simulations consider the potential effects of five policy alternatives: Increase the general income exclusion (GIE) from $20 to $80. Increase the earned income exclusion (EIE) from $65 to $260. Increase the federal benefit rate (FBR) by $50 for individuals and $75 for couples and eliminate the GIE. Increase the asset threshold to $3,000 for individuals and $4,500 for couples. Increase the asset threshold to $6,000 for individuals and $9,000 for couples. Using 1991 microdata from the Survey of Income and Program Participation (SIPP) matched to Social Security Administration administrative records and making adjustments reflecting aggregate program statistics, we present the results of our simulations for December 1999. The results show substantial variation in the simulated effects of the five policy alternatives along the various outcome dimensions considered. The simulated effects on the poverty gap of the elderly population range from a 7.9 percent reduction ("Increase the GIE from $20 to $80") to a 0.1 percent reduction ("Increase the EIE from $65 to $260"). All simulated interventions are expected to increase the rate of SSI participation among the elderly from a high of 20.3 percent ("Increase the GIE from $20 to $80") to a low of 0.5 percent ("Increase the EIE from $65 to $260"). We also find that the interventions that have greater estimated effects in terms of increased participation and reduced poverty tend to cost more. At the high end, we estimate that increasing the GIE from $20 to $80 could raise annual federal SSI cash benefit outlays by about 46 percent, compared with only 0.9 percent for increasing the EIE from $65 to $260. Similar to the EIE intervention, raising the resource thresholds by 50 percent would reduce the overall poverty gap of the elderly by only 0.2 percent, would increase SSI participation only modestly (by 1.3 percent), but would entail slightly higher program costs (by 1.4 percent). Increasing the asset threshold by 200 percent would have higher estimated effects on all three outcomes, but it would still be associated with relatively low increases in both costs and benefits. Finally, the simulated effects on the three key outcomes of increasing the FBR by $50 for individuals and $75 for couples, combined with eliminating the GIE, are relatively large but are clearly less substantial than increasing the GIE from $20 to $80. This work relies on data from the SIPP matched to administrative data on federal SSI benefits that provide a more accurate picture of SSI participation than has been feasible for previous studies. We simulate eligibility for federal SSI benefits by applying the program rules to detailed information on the characteristics of individuals and couples based on the rich array of demographic and socioeconomic data in the SIPP, particularly the comprehensive information SIPP provides on assets and monthly income. A probit model is estimated to analyze factors affecting participation among the eligible elderly. Finally, we conduct the policy simulations using altered program rules represented by the policy alternatives and predicted participation probabilities to estimate outcomes under simulated program rules. We compare those simulated outcomes to observed outcomes under current program rules. The results of our simulations are conditional on the characteristics of participants and eligibles in 1991, but they also reflect aggregate adjustments capturing substantial changes in overall participation and program benefit levels between 1991 and 1999.     

Technology and Criminal Justice

The extent and use of technology in the British criminal justice system is uneven. Two areas are examined; first where technology is used in prisons or by the police, and secondly when it is used to develop new sanctions, as with electronic monitoring, or as attachments to existing sanctions such as drug testing. Technology in prisons is mainly in the form of perimeter security, and in the police through CCTV cameras or databases. In the second the emphasis is on tracker systems which gives the supervisor greater control. Technological development in criminal justice is not without its critics. Some regard existing technological developments with suspicion, seeing them as a means of enhancing control, or as an attack on traditional liberal values, or more importantly as an extension of a form of behaviourism which is concerned only with the observable act. Others note the expensive failures of technology where systems fail to work or are delivered late. It is suggested a Government study is required to examine existing technologies and its likely future impact whether on the criminal justice system generally or on those working within it or as inmates.     

An Evaluation of the Use of Videotaped Evidence for Juvenile Witnesses in Criminal Courts in England and Wales

For the first time, the UK Criminal Justice Act (1991) allowed the videotaped evidence of a child to be substituted for the child's evidence-in-chief in a criminal court. The present study is an evaluation of that legislation. One hundred and fifty children were observed testifying in a criminal court in the UK. The use of the videotaped evidence and subsequent cross-examination of the child witness (usually via the closed circuit television system) was also observed. The data base from the Lord Chancellor's Department of all trials involving child witnesses in England and Wales was also analysed. The results showed that the introduction of the video technology into the criminal courts reduced the levels of stress of child witnesses but did not increase the conviction rates.     

Ambassadors in the community? Labour Party members in society

A political party's members are its ambassadors in the wider community. Based on a survey of Labour party members in Nuneaton, this article investigates the extent to which party members qua party members are visible amongst their friends and colleagues. It finds that there are few closet Labour party members. Most are known to friends and (slightly less commonly) colleagues. Party members also articulate a political message, discussing politics with friends and work colleagues. Around half of party members believe that they influence others as a result of their discussions; of those who are asked their opinions by friends, almost three-quarters believe that they influence others. Labour party members in Nuneaton are thus a visible and articulate manifestation of the party. The article ends by considering whether this is likely to be true in other constituencies, for other parties, and at other times.     

Globalization and the erosion of democracy

Despite the apparent development and spread of liberal democratic state forms in the 1980s and 1990s, possibilities for genuine democratic governance overall are declining. Firstly, the emergence and consolidation of modern liberal democracy was inextricably intertwined with the development of the nation–state and is profoundly socially embedded in that structural context. Secondly, in today's globalizing world, cross–cutting and overlapping governance structures and processes increasingly take private, oligarchic (and mixed public/ private) forms; hegemonic neoliberal norms are delegitimizing state–based governance in general; and democratic states are losing the policy capacity necessary for transforming democratically generated inputs into authoritative outputs. Consequently, robust constraints limit the potential for (a) reinstitutionalizing the 'democratic chain' between accountability and effectiveness, (b) rearticulating the multitasking character of authoritative institutions and (c) renewing the capacity of authoritative agents to make the side–payments and to undertake the monitoring necessary to control free–riding and assimilate alienated groups. Rather than a new pluralistic global civil society, globalization is more likely to lead to a growth in inequalities, a fragmentation of effective governance structures and the multiplication of quasi–fiefdoms reminiscent of the Middle Ages.     

The rise and fall of the legal expert system†

Those very few of us who were critical of the rise of legal expert systems in the early 1980s probably wonder, in idle moments, whether there is a possibility of rejuvenation of an approach which was once multi-various and is now obscure and esoteric. Is it possible that after rising and falling, that legal expert system research programme could rise again? What were the conditions which gave impetus to the field and could they be repeated? In this article I want to return, with a personal viewpoint, on the rise of expert systems and why - despite their failure - the appeal of commoditising legal expertise continues to allure the unwary.