Joint impact of multiple observations on a subset of variables in multiple linear regression

In multiple linear regression analysis, each observation affects the fitted regression equation differently and has varying influences on the regression coefficients of the different variables. Chatterjee & Hadi (1988) have proposed some measures such as DSSE_ij (Impact on Residual Sum of Squares of simultaneously omitting the ith observation and the jth variable), F_j (Partial F-test for the jth variable) and F_j(i) (Partial F-test for the jth variable omitting the ith observation) to show the joint impact and the interrelationship that exists among a variable and an observation. In this paper we have proposed more extended form of those measures DSSE_IJ, F_J and F_J(I) to deal with the interrelationships that exist among the multiple observations and a subset of variables by monitoring the effects of the simultaneous omission of multiple variables and multiple observations.     

Book reviews

Nathan Glazer Ethnic Dilemmas Harvard, Harvard University Press. 1985

Giddens, Anthony The Constitution of Society, Berkeley, University of California, 1985, pp.XXXVII, 402. Notes, glossary, diagrams, bibliographic notes and index.

Jeremy Rifkin Declaration of a Heretic. Boston. London, Melbourne and Henley, Routledge and Kegan Paul, 1985, pp.X,140.

Ted Benton The Rise and Fall of Structural Marxism: Althusser and his Influence, New York, St.Martin's Press, 1984, pp. VII,259.

Raymond L. Garthoff Détente and Confrontation Washington, The Brookings Institution, 1985, pp.XVI,1126.

Joseph J. Collins The Soviet Invasion of Afghanistan. A Study in the Use of Force in Soviet Foreign Policy, Massachusetts/Toronto, D.C. Heath and Company/Lexington, 1986, pp. XV, 195.

Jan Shipps Mormonism: The Story of a New Religious Tradition, Chicago, University of Illinois Press, 1985, pp.211.

Robert Jay Lifton Home from the War: Vietnam Veterans: Neither Victims nor Executioners, New York, Basic Books, 1985, pp.478     

How can David orchestrate resources to enhance firm performance? A dynamic approach to coping with resource constraints

Given that the possession of abundant resources does not always guarantee superior firm performance, this study proposes a dynamic approach to enhancing firm value. Building on the resource orchestration thesis, we investigate how firms facing resource constraints enhance their capabilities over time by orchestrating resources and how this resource orchestration can play a role in improving firm performance. Using the dynamic perspective, this study identifies four resource orchestration modes, which are specified based on how a given firm dynamically allocates its resources to technology (enacted by R&D activities) and marketing (enacted by advertising activities). Accordingly, we claim that firms with resource constraints can enhance their performance by escalating or altering their resources over time. To test our hypotheses, we used a sample of 4078 small and medium-sized enterprises in manufacturing industries between 1984 and 2018. We found that focus escalation for technology positively affects firm performance, captured by Tobin's q, and that focus alternation toward either technology or market is positively related to firm performance. Finally, we discuss the theoretical and practical implications of our findings.     

Understanding manager resistance to blockchain systems

Blockchain technology has received much attention in the media and there is an increasing interest amongst organizations within financial services due to the potential benefits. As blockchain-based systems are a nascent technology, the requirements of the technology need to be understood, to allow blockchain systems to be successfully integrated within financial service organizations. There are gaps in academic research in understanding how managers evaluate the value of a blockchain-based system. This study develops a model to explain manager resistance to implementing blockchain-based systems in financial services organizations. This research advances the theoretical understanding of managers’ perspectives on blockchain-based systems and models their resistance to blockchain technology.     

Audience effects on solitary faces during imagery: Displaying to the people in your head

Subjects imagined situations in which they reported enjoying themselves either alone or with others. Electromyographic (EMG) activity was recorded bilaterally from regions overlying thezygomatic major muscles responsible for smiling. Controlling for equal rated happiness in the two conditions, subjects showed more smiling in high-sociality than low-sociality imagery. In confirming imaginary audience effects during imagery, these data corroborate hypotheses that solitary facial displays are mediated by the presence of imaginary interactants, and suggest caution in employing them as measures of felt emotion.Avery Gilbert and Amy Jaffey had compelling insights throughout the course of study. We thank Paul Ekman, Carroll Izard, and Paul Rozin for extensive comments on earlier drafts. We also thank Bernard Apfelbaum, Jon Baron, Janet Bavelas, John Cacioppo, Linda Camras, Dean Delis, Rob DeRubeis, Alan Fiske, Stephen Fowler, Greg McHugo, Harriet Oster, David Premack, W. John Smith, and David Williams for their valuable comments and suggestions.     

Minimal treatments and problem gamblers: A preliminary investigation

In view of the increasing popularity of minimal intervention treatments for problem drinking, a self-help manual for people who wish to reduce or stop gambling was prepared. Twenty-nine (ACT residents) who responded to advertisements for help with problem gambling were allocated to either of two minimal treatments, Manual (only) and Manual & Interview. On average, clients from both groups reduced the frequency of their gambling sessions, frequency of overspending, and amount spent per week in the first three months and next three months after first contact, but expenditure per session increased from three to six months, after an initial improvement. There was no evidence that a single in-depth interview added to the effectiveness of the manual.This project was funded by a grant from the Australian National University Faculties Research Fund.     

“Consumer Confidence” Indexes as social indicators

Consumer Confidence Indexes can be sensibly used in economic and social research conducted in theoretical and methodological framework of social indicators research. They are good predictors of other attitudes, such as voting preferences. Voting preferences are determined much more strongly by expectations of changes in economic conditions than by evaluations of present situation. On the other hand, Consumer Sentiment Indexes — irrespective whether they concern future or present times — are correlated more strongly with leading than with coincident indexes of economic cycles. That proves very important role of predictions, expectations and hopes in attitude formation.     

When push comes to shove: implementing VBAC practice guidelines

The dramatic increase in U.S. cesarean sections over the past two decades has been significantly driven by repeat C-sections. In response to this trend, clinical guidelines recommending vaginal birth after cesarean-section (VBAC) have been promulgated by national organizations. Adherence to these guidelines would reduce the number of repeat C-sections, lower the overall C-section rate, and improve both the quality and the cost of health care. While these guidelines have received professional endorsement, their implementation has been clouded by issues of patient acceptance and provider payment. To examine implementation of these guidelines by health care organizations, the authors surveyed 156 members of the American College of Physician Executives to determine their policies, practices, and attitudes toward VBAC guidelines. Those surveyed generally were medical directors in HMOs, hospitals, and other practice settings. The findings indicate that the health care organizations represented by these physician executives have not consistently implemented VBAC guideline and that they are reluctant to hold physicians, their patients, or hospitals accountable for the financial, utilization, and quality impact of the elective decision ot to pursue appropriate VBACs. We conclude that, even when widely accepted, clinical practice guidelines may be ineffective in reducing the costs or improving the quality of medical care.