Information technologies and the

conclusion The evolution in the role of middlemen has many important implications at the macro-economic level as well. In many markets, the negative employment effects of labor-saving technologies are offset by increases in the demand for labor as transaction costs fall and additional labor is needed to produce more goods and services. As discussed above, middlemen operate successfully in markets when private transactions are costly and inefficiencies exist. Many traditional aspects of this role are being replaced by information technologies. Generally, information technologies are a close substitute for match-making services, but are less suited for reducing privately held asymmetric information. The reduction in transaction costs and improved efficiencies in match mak-ing provided by information technologies increases the demand for expert services which further increases the returns to education and widens the earnings gap. The widening should be greatest in industries that concentrate on match-making services such as real estate, however a widening is likely to be present in most sectors. Middle-men with expertise beyond match making will remain viable, while those lacking value-adding expertise will be rapidly marginalized.     

Caffeine consumption, expectancies of caffeine-enhanced performance, and caffeinism symptoms among university students

The expectancies paradigm developed in alcohol research was used to study caffeine consumption and signs of caffeinism in two groups of college students. A survey questionnaire was developed to gather self-report data on expectations of caffeine-enhanced performance (EP-CAFF), level of beverage caffeine consumed daily, and DSM-111 caffeinism signs reportedly experienced after consumption of caffeinated beverages. A positive association between EP-CAFF and both caffeine consumption and caffeinism signs was predicted. In both initial (n = 527) and cross-validation (n = 270) samples, significant correlations between EP-CAFF scores and both caffeine consumption and caffeinism symptoms were found. A small, but statistically significant, relationship was also found between caffeinism symptoms and both alcohol consumption and cigarette smoking. Of the 797 subjects in the combined sample, 151 (18.9%) endorsed five or more DSM-III caffeinism signs. Subjects endorsing five or more signs of caffeinism scored higher on the EP-CAFF scale, and consumed more caffeine and alcohol in both studies and smoked more cigarettes in study one--but not in study two--than did subjects who endorsed fewer than five caffeinism signs. Results support the utility of extending the expectancies model of substance use motivation from alcohol to caffeine.     

The influence of urine from asymptotic laboratory populations on sexual maturation in prairie deermice

Summary Male and female prairie deermice housed singly from weaning (21 days) until 40 days of age had urine from one of the following sources applied daily to their nostrils: sexually mature laboratory population males or females, and sexually mature breeder males or females from our laboratory colony. Other males and females were treated with water. Records were obtained of the weights of the tests, seminal vesicles and bacula of males and the ovaries and uteri of females at 40 days of age. The major results of this study were as follow: Female urine from sexually mature and inhibited population or isolated mice stimulated the development of the male reproductive organs significantly more than water or male urine. Male urine applied to young males did not differentially affect the weights of their reproductive organs compared with water and thus showed no inhibition effects. The reproductive organs of females treated with male urine did not differ significantly in weight from those of females treated with female urine. Females treated with water developed significantly larger uteri than those treated with urine from sexually mature population females (P≤0.02), inhibited population females (P<0.001) and inhibited population males (P<0.007).     

Risk factors and correlates of dating violence: the relevance of examining frequency and severity levels in a college sample

To determine whether categorizing levels of violence along dimensions of frequency and severity would result in informative distinctions among individuals using dating violence, reported use of physical violence, along with variables theorized to be related to use of force in intimate relationships, was assessed in a sample of 617 college students (males = 290; females = 327). When participants' scores were analyzed by dichotomizing them along the lines of ever versus never using dating violence, numerous past findings were replicated. However, participants using a higher frequency of force were distinguished by needing to control their partner and by less inhibition in expressing their anger. Higher severity of force by an individual was predicted only by a need to control his/her dating partner. Implications for these findings were discussed.     

Illness career descent in institutions for the elderly

This paper examines the social psychological consequences of illness careers in a retirement facility. As elderly residents' health declines, they experience an illness career descent. This refers to the movement through the social structure of the healthcare facility as a consequence of the downward trajectory of chronic illness. Illness career descent requires the formal relocation of the individual and the informal social consequences of loss of control, stigmatization, and segregation from prior friendship networks. Individuals react in a three-stage manner. At first, residents resist being moved down. Next, there is a negative impact on their self-image as relocated residents accept the evaulation by staff that they have become less competent. Third, they adjust to their new location and enhance their self-image by developing new roles, finding a poor dear, re-evaluating prior stereotypes, and engaging in post-decisional dissonance reduction.The author wishes to express his deepest appreciation to Jacob Climo, Peter Conrad, Stan Kaplowitz, and Shulamit Reinharz for their encouragement and their suggestions on earlier drafts of this paper.     

Making Privatization Work: Utilizing a Scorecard Model of Human Resource Strategy

Three-fourths of privatization efforts fail. Analyses of the other one-fourth have overlooked what is arguably the single most important element: successful management of human resources. In establishing the culture of change necessary to effect competitive initiatives and in motivating employees toward innovation and accountability, a scorecard-based human resource strategy is at the center of it all. A discussion of the strategic role of human resource management supporting privatization efforts in general, and of the remarkably successful Charlotte, North Carolina experience in particular, offers important lessons. Detailed here is a rubric of what works and why.     

The Potential Impact of ‘Public Access’ Legislation on Access to Forestry Literature

There have been increasing calls for the United States (U.S.) government’s implementation of broad public access policies mandating free online access to federally funded research. This study examines the potential impact of such a policy on peer-reviewed forestry literature. The authors analyze information about federal government authorship, federal government funding, and U.S. authorship indicated in articles published in five core forestry journals in 2006. The results of the analysis provide evidence that federal public access legislation would have a significant impact on the accessibility of forestry literature published in leading journals in the field.     

Maximum likelihood from spatial random effects models via the stochastic approximation expectation maximization algorithm

We introduce a class of spatial random effects models that have Markov random fields (MRF) as latent processes. Calculating the maximum likelihood estimates of unknown parameters in SREs is extremely difficult, because the normalizing factors of MRFs and additional integrations from unobserved random effects are computationally prohibitive. We propose a stochastic approximation expectation-maximization (SAEM) algorithm to maximize the likelihood functions of spatial random effects models. The SAEM algorithm integrates recent improvements in stochastic approximation algorithms; it also includes components of the Newton-Raphson algorithm and the expectation-maximization (EM) gradient algorithm. The convergence of the SAEM algorithm is guaranteed under some mild conditions. We apply the SAEM algorithm to three examples that are representative of real-world applications: a state space model, a noisy Ising model, and segmenting magnetic resonance images (MRI) of the human brain. The SAEM algorithm gives satisfactory results in finding the maximum likelihood estimate of spatial random effects models in each of these instances.     

Lifetime Buy Decisions with Multiple Obsolete Parts

Life‐cycle mismatch occurs when the life cycles of parts end before the life cycles of the products in which those parts are used. Lifetime buys are one tactic for mitigating the effect of part obsolescence, where a quantity of parts is purchased for the remaining life of a product. We extend prior work that determines optimal lifetime buy quantities for one product with one obsolete part by providing an analytic solution and two simple heuristic policies for the optimal lifetime buy quantities when many parts become obsolete over a product's life cycle. We determine which of our two heuristics is most accurate for different product life cycles, which yields a metaheuristic with increased accuracy. That analysis also reveals critical perspectives in making lifetime buy decisions with nonstationary life‐cycle demand patterns.