Interpreting Bivariate Regression Coefficients: Going Beyond The Average

Statistics, econometrics, investment analysis, and data analysis classes often review the calculation of several types of averages, including the arithmetic mean, geometric mean, harmonic mean, and various weighted averages.  This note shows how each of these can be computed using a basic regression framework.  By recognizing when a regression model is computing one of these averages, students can properly interpret these types of regressions.  Similarly, by seeing how these averages fit into a common framework, students can have a better understanding of the different calculations

Unions and Democracy: When Do Nonmembers Have Voting Rights?

La Salud Sexual y Reproductiva se define como “un estado general de bienestar físico, mental y social, y no de mera ausencia de enfermedades o dolencias” (Stampar,1946). Sobre las acciones hacia adolescentes, ha sido dilemático y conflictivo el trato en relación a la vivencia de la sexualidad y a los aspectos referidos a las decisiones de esta población. La Conferencia Internacional de Población y Desarrollo de Naciones Unidas aborda las necesidades de la población adolescente, y recomienda la implementación de servicios específicos resaltando el derecho de los y las adolescentes “a la intimidad, confidencialidad, el respeto y el consentimiento basado en una información correcta y respetuosa de los valores culturales y las creencias religiosas” (CIPD, 1994). En marzo de 2005, se crea en Uruguay el Programa Nacional de Salud Adolescente, con el objetivo de construir una política nacional de salud integral para la adolescencia, basada en principios de universalidad, equidad, accesibilidad, territorialidad y respeto por la diversidad. En el marco de estas acciones, se crean luego los “espacios adolescentes” los cuales se presentan como un espacio diferencial de atención y promoción de la salud con especial énfasis en el enfoque de derecho y género. Este estudio pretende evaluar el funcionamiento de una selección de espacios diferenciales destinados a adolescentes con el fin de contribuir a su desarrollo, expansión y fortalecimiento

Misleading Betas: An Educational Example

The dual-beta model is a generalization of the CAPM model. In the dual-beta model, separate beta estimates are provided for up-market and down-market days. This paper uses the historical “Anscombe quartet” results which illustrated how very different datasets can produce the same regression coefficients to motivate a discussion of the dual-beta model. Using data from 39 mutual funds, it is shown how very different dual-beta models can lead to the same CAPM beta estimates, much like the Anscombe quartet scenarios

Improved Margin Of Error Estimates For Proportions In Business: An Educational Example

This paper presents the Agresti & Coull “Adjusted Wald” method for computing confidence intervals and margins of error for common proportion estimates.  The presented method is easily implementable by business students and practitioners and provides more accurate estimates of proportions particularly in extreme samples and small sample situations.  The proposed method may have particular applications to focus group analysis, industry benchmarking, and destructive testing sampling.  The paper discusses a computational strategy and several comparison examples

Statistical Analysis Of A Class: Monte Carlo And Multiple Imputation Spreadsheet Methods For Estimation And Extrapolation

The Monte Carlo method and related multiple imputation methods are traditionally used in math, physics and science to estimate and analyze data and are now becoming standard tools in analyzing business and financial problems.  However, few sources explain the application of the Monte Carlo method for individuals and business professionals who are not immersed in the realm of mathematics or science.  This paper introduces these Monte Carlo methods for the non-mathematician and business student, providing examples where the Monte Carlo method is applied when only small samples are available.  Statistical analysis and statistically sound extrapolation of sample characteristics to the larger class population can be facilitated by applying Monte Carlo methods and the related concept of multiple imputation, which is also explained.  Appendices provide step-by-step instructions for using two popular spreadsheet add-ins to run Monte Carlo based analysis

Does Political and Economic Freedom Matter for Inbound Tourism? A Cross-National Panel Data Estimation

The paper examines the impact of political and economic freedom on inbound tourism for over 110 countries during 1995-2012. Panel country fixed-effects techniques are utilized to examine the relationship after controlling for other factors that contribute to inbound tourism. The results show that civil liberties and economic freedom (among several other freedom measures) are positively and significantly associated with inbound tourism. Examination of the moderation effect reveals that civil liberties (economic freedom) tend to play a more influential role on inbound tourism when the level of economic freedom (civil liberties) is relatively low

Twenty-five years of end-user searching, Part 1: Research findings

This is the first part of a two-part article that reviews 25 years of published research findings on end-user searching in online information retrieval (IR) systems. In Part 1 (Markey, 2007 ), the author seeks to answer the following questions: What characterizes the queries that end users submit to online IR systems? What search features do people use? What features would enable them to improve on the retrievals they have in hand? What features are hardly ever used? What do end users do in response to the system's retrievals? Are end users satisfied with their online searches? Summarizing searches of online IR systems by the search features people use everyday makes information retrieval appear to be a very simplistic one-stop event. In Part 2, the author examines current models of the information retrieval process, demonstrating that information retrieval is much more complex and involves changes in cognition, feelings, and/or events during the information seeking process. She poses a host of new research questions that will further our understanding about end-user searching of online IR systems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/56093/1/20462_ftp.pd

Exploratory information searching in the enterprise: A study of user satisfaction and task performance

No prior research has been identified which investigates the causal factors for workplace exploratory search task performance. The impact of user, task and environmental factors on user satisfaction and task performance was investigated through a mixed methods study with 26 experienced information professionals using enterprise search in an oil and gas enterprise. Some participants found 75% of high value items, others found none with an average of 27%. No association was found between self-reported search expertise and task performance, with a tendency for many participants to overestimate their search expertise. Successful searchers may have more accurate mental models of both search systems and the information space. Organizations may not have effective exploratory search task performance feedback loops, a lack of learning. This may be caused by management bias towards technology not capability, a lack of systems thinking. Furthermore, organizations may not ‘know’ they ‘don’t know’ their true level of search expertise, a lack of knowing. A metamodel is presented identifying the causal factors for workplace exploratory search task performance. Semi-structured qualitative interviews with search staff from the Defence, Pharmaceutical and Aerospace sectors indicates the potential transferability of the finding that organizations may not know their search expertise levels