Influence diagnostics in a multivariate normal regression model with general parameterization

Patriota and Lemonte [24] introduced a quite general multivariate normal regression model. This model considers that the mean vector and the covariance matrix share the same vector of parameters. In this paper we present some influence assessment for this model, such as the local influence, total local influence of an individual and generalized leverage which are discussed. Additionally, the normal curvatures for local influence studies are derived under some perturbation schemes.     

Making Meanings,Meaning Identity: Hmong Adolescent Perceptions and Use of Language and Style as Identity Symbols

Using qualitative interview data gathered from 28 Hmong adolescents, we examined the meaning ascribed to language and style and how language and style behaviors are used to distinguish identity. We found that the participants used language and style to define their own ethnic group membership and cultural identities. Moreover they inferred meaning from these identity behaviors to discern which peer groups are desirable (those who wear American style clothing and are bilingual) and which are of low social status (“fobby” style clothing and monolingual). The cultural identity symbols used by participants reveal heterogeneity among Hmong adolescent peer groups and evolving definitions of what it means to be Hmong in America.     

Grading with norm-referenced or criterion-referenced measurements: To curve or not to curve,that is the question

Assigning grades is an integral and everyday part of social work education. However, social work educators, especially those teaching the academically-based as opposed to practice-based courses, must decide whether to use norm-referenced or criterion-referenced measurements to grade exams and other assignments. Norm-referenced measurement is commonly called grading on a curve in higher education. While grading on the curve is not obsolete in academia, I have eliminated it in my courses. New and perhaps experienced social work educators may benefit from a review of both grading methods. This article examines both sides of a grading issue relevant to the wider context of higher education and, therefore, relevant to social work education. Grading with norm-referenced or criterion-referenced measurements is reviewed along with issues related to both types of grading. I will describe why I grade with criterion-referenced measurement and why I believe it is a better choice for social work education.     

Understanding information systems infrastructure in engineering SMEs: A case study

The benefits of integrated enterprise-wide information systems (IS), such as Enterprise Resource Planning (ERP) systems, are widely accepted. The implementation of such systems in large organisations is established with many in their second or third generation. However, in small to medium-sized enterprises (SMEs) the maturity and extent of their IS infrastructure is less clear. In engineering SMEs, this infrastructure needs to support not only business processes but also the activities of design and manufacture.In this case study, our goal is to provide a better understanding of current IS infrastructure, the functional elements of IS infrastructure, integration and expenditures are explored in ten engineering SMEs. A model of IS functionality is developed and used to identify and classify functional elements within the firms and to compare and contrast the IS infrastructures. The findings are contrasted with the SME literature and conclusions and implications developed.     

The folder feedback system: Making research content more understandable,enjoyable, and usable 1

This paper describes the use and evaluation of the folder feedback system. The folder feedback system is a useful teaching tool based in principles of adult learning. It is designed to help organize student learning, increase communication with the instructor, insert an element of fun into the class, and assist with student/teacher relationship building. An evaluation of the teaching tool produced mixed results. The treatment group received higher grades than the comparison group, yet in all other measures no differences were found.     

Estimating the prevalence of sensitive behaviour and cheating with a dual design for direct questioning and randomized response

Randomized response is a misclassification design to estimate the prevalence of sensitive behaviour. Respondents who do not follow the instructions of the design are considered to be cheating. A mixture model is proposed to estimate the prevalence of sensitive behaviour and cheating in the case of a dual sampling scheme with direct questioning and randomized response. The mixing weight is the probability of cheating, where cheating is modelled separately for direct questioning and randomized response. For Bayesian inference, Markov chain Monte Carlo sampling is applied to sample parameter values from the posterior. The model makes it possible to analyse dual sample scheme data in a unified way and to assess cheating for direct questions as well as for randomized response questions. The research is illustrated with randomized response data concerning violations of regulations for social benefit.     

The Victorian Gambling Screen: Reliability and Validation in a Clinical Population

There is a need to establish reliability and the various forms of validity in all measures in order to feel confident in the use of such tools across a wide diversity of settings. The aim of this study is to describe the reliability and validity of the Victorian Gambling Screen (VGS) and in particular one of the sub-scales (Harm to Self—HS) in a specialist problem gambling treatment service in Adelaide, Australia. Sixty-seven consecutive gamblers were assessed using a previously validated clinical interview and the VGS (Ben-Tovim et al., The Victorian Gambling Screen: project report. Victorian Research Panel, Melbourne, 2001). The internal consistency of the combined VGS scales had a Cronbach’s alpha of .85 with the HS scale .89. There was satisfactory evidence of convergent validity which included moderate correlations with another measure of gambling—the South Oaks Gambling Screen. There were also moderate correlations with other measures of psychopathology. Finally, how the VGS may best be used in clinical settings is discussed.     

An Empirical Analysis of Backlog,Inventory, Production,and Price Adjustments: An Application of Recursive Systems of Log-Linear Models

This article presents an empirical analysis of firms' order backlogs, inventories, production, and price adjustments to unanticipated demand shocks. The data are obtained from quarterly INSEE Business Survey Tests on firms' realizations, expectations, and appraisals of some various economic variables. The analysis is based on the formulation and the estimation of a recursive system of conditional log-linear probability models.     

Combinatoric classification of multivariate normal variates

Consider classifying an n × I observation vector as coming from one of two multivariate normal distributions which differ both in mean vectors and covariance matrices. A class of dis-crimination rules based upon n independent univariate discrim-inate functions is developed yielding exact misclassification probabilities when the population parameters are known. An efficient search of this class to select the procedure with minimum expected misclassification is made by employing an algorithm of the implicit enumeration type used in integer programming. The procedure is applied to the classification of male twins as either monozygotic or dizygotic.     

A time series model with random coefficients

There are many time series applications where an experi­menter observes the simultaneous responses of several sub­systems over time. In these instances one is often not interested in the parameters of individual subsystems, but rather in an overall characterization of the system in question. Under the assumption that subsystems are independent and first order autoregressive, the present paper presents two methods for estimating the distribution of the subsystem coefficients.