Imperfect Information and Staggered Price Setting

Many Keynesian macroeconomic models are based on the assumption that firms change prices at different times. This paper presents an explanation for this "staggered" price setting. We develop a model in which firms have imperfect knowledge of the current state of the economy and gain information by observing the prices set by others. This gives each firm an incentive to set its price shortly after as many firms as possible. Staggering can be the equilibrium outcome. In addition, the information gains can make staggering socially optimal even though it increases aggregate fluctuations.

Inflation and Uncertainty at Long and Short Horizons

macroeconomics, Inflation, Uncertainty, Long Horizons, Short Horizons

Can People Compute? An Experimental Test of the Life Cycle Consumption Model

This paper presents the results of an experimental study of the life cycle model in which subjects were asked to make preferred consumption choices under hypothetical life cycle economic conditions. The questions in the experiment are designed to test the model's assumption of rational choice and to elicit information about preferences. The subjects' responses suggest a widespread inability to make coherent and consistent consumption decisions. Errors in consumption decision-making appear to be very substantial and, in many cases, systematic. In addition, the experiment's data strongly reject the standard homothetic, time-separable life cycle model. The principal specific findings of the laboratory experiment are: (1) Subjects displayed significant inconsistencies in their consumption decisions; each of the subjects, in at least two pairs of economically identical situations, chose consumption values that differed by 20 percent or more. From the perspective of the standard life cycle model, error in decision-making accounts, on average, for roughly half of the variation in consumption. (2) A sizeable fraction of subjects undervalued future earnings relative to present assets; i.e., they systematically overdiscounted future earnings. (3) Almost all subjects exhibited oversaving behavior, apparently because they underestimated the power of compound interest. (4) The hypothesis that intertemporal consumption preferences are uniform across individuals is strongly rejected. Indeed, the demographic characteristics of subjects are significant determinants of consumption choice in the experiment.

Levels and Variations of Violation in Rape.

This chapter investigates the variations in crime scene behaviour revealed in a sample of victim statements in cases of stranger sexual assault. Building on previous findings by Canter and Heritage (1990), and Canter (1994), it was hypothesised that there existed a scale of differing levels of violation by the offender. This scale, based upon actions in the offence, ranged from personal violation, through to physical violation and finally, at the most extreme level, sexual violation. Offences could also be differentiated at the personal and physical levels in terms of hostile, controlling, stealing or involving thematic emphases to the criminal’s actions. To test these hypotheses, crime scene data from the first detected offences of 112 British rapists were analysed using a multi-dimensional scaling procedure to explore the relationships amongst crime scene actions. The results provided empirical support for the four action themes as different expressions of various intensities of violation. The implications that these findings have for the investigation of stranger sexual assault and treatment of victims are discussed

Growth hormone and tissue growth factors in the pathogenesis of diabetic retinopathy

The aim of this work was to examine the role of Growth Hormone (GH) and tissue growth factors in the pathogenesis of diabetic retinopathy, and to investigate the mechanism of excessive GH secretion in diabetes. Levels of GH and insulin-like growth factor-I (IGF-I) (the principal mediator of the growth promoting activity of GH) were measured in diabetic patients with retinopathy and control subjects. The concentration of basic fibroblast growth factor (bFGF), a potent angiogenic growth factor, was also examined in vitreous and retinal extracts. 24h studies confirmed increased GH and normal IGF-I levels during poor diabetic control suggesting impaired IGF-I production. Serum IGF-I was inversely correlated with HbA1 concentration. Reduced feedback inhibition by IGF-I when control is poor could contribute to excessive GH release. In addition, pretreatment with GH failed to suppress the GH response to GH-releasing hormone (GHRH) in some patients indicating altered GH feedback control. Relative resistance to somatostatin was inferred from the results of treatment with octreotide, a potent somatostatin analogue. GH hypersecretion in diabetes is likely to be a product of several different mechanisms. No correlation was found between the development of background retinopathy and changes in serum IGF-I concentration, in patients commencing continuous subcutaneous insulin infusion. A significant increase in mean serum IGF-I occurred at the onset of proliferative retinopathy in patients treated conventionally (281 ± 54 versus 196 ± 58 micrograms/l; p <0.05). Cultured retinal endothelial cells were demonstrated to release IGF-I but not bFGF into the cell medium. A different release mechanism is likely for bFGF which was abundant in whole retinal extracts. In the diseased diabetic retina, cell damage could release bFGF which would then induce cell competence in surviving endothelial cells and fibroblasts. By allowing the cells to complete the cell cycle, the increase in IGF-I levels could play a crucial role in promoting cell proliferation and neovascularisation

Design and Development of Software Tools for Bio-PEPA

This paper surveys the design of software tools for the Bio-PEPA process algebra. Bio-PEPA is a high-level language for modelling biological systems such as metabolic pathways and other biochemical reaction networks. Through providing tools for this modelling language we hope to allow easier use of a range of simulators and model-checkers thereby freeing the modeller from the responsibility of developing a custom simulator for the problem of interest. Further, by providing mappings to a range of different analysis tools the Bio-PEPA language allows modellers to compare analysis results which have been computed using independent numerical analysers, which enhances the reliability and robustness of the results computed.

Cashing in on Seafood

Stephen Heard graduated from the University of Rhode Island in 1970 with a degree in business administration. He started his career by signing up as a management trainee at Woolworth’s Department Store in Wellesley, Massachusetts. It didn’t take him long to realize he missed his calling: being by the Rhode Island shoreline and employed in the fishing industry. Nearly 35 years later, Stephen is a self-made multimillionaire, having followed both his passion for entrepreneurship and for living his life on the Atlantic coast

The relationship between teachers' understanding of the nature of science and their science practice : four case studies from an urban primary school.

This is a digitised version of a thesis that was deposited in the University Library. If you are the author and you have a query about this item please contact PEARL Admin ([email protected])Merged with duplicate record (10026.1/432) on 03.01.2017 by CS (TIS)This thesis explores the relationship between a teacher's understanding of the nature of science and her practice. The idea that teachers' understanding of the nature of science is a powerful determinant of their actions in the classroom has a strong intuitive appeal. Research over the last forty years has provided inconclusive results; however, there is a clear implication within recent central policy on teacher education that such knowledge should translated directly into practice. This has led to the identification within teacher training, materials of specific expectations regarding understanding of the nature of science (DfEE 1998a). This thesis presents four case studies of the science teaching of primary teachers. The studies derive from data collected over the course of a year and analyse evidence of the teachers' ideas, both tacit and espoused, about the nature of science against their practice in the classroom. The research employed a methodology unlike other studies in the field. Primary teachers frequently lack experience of reflection on the philosophy of science, and their actions may convey tacit ideas different from those they espouse. In order to ensure that, a mechanism existed to facilitate elicitation of the teachers' philosophical understanding, to render possible the identification of any tacit ideas and to enable the inherent dialectical nature of theory and action within practice to be accommodated, the participating teachers were encouraged to engage in action research on their own practice. Data generated by this personal inquiry then served as evidence for the main research questions. This methodology yields results which are closely derived from the everyday reality of teachers' practice. The findings indicate that teachers' understanding of the nature of science does not translate directly into predictable approaches to science teaching. Teachers' understanding of the nature of science is seen to be mediated strongly by their pedagogical beliefs and aims and it is these beliefs that assume overriding importance in the derivation of science practice. These findings extend previous research results. They suggest that the development of science practice will need to have regard for factors other than mere extension of knowledge, raising implications for both preservice and inservice teacher education.Rolle School of Education Researc

Mid-frequency readers

This article describes a new free extensive reading resource for learning the mid-frequency words of English and for reading well known texts with minor vocabulary adaptation. A gap exists between the end of graded readers at around 3,000 word families and the vocabulary size needed to read unsimplified texts at around 8,000 word families. Mid-frequency readers are designed to fill this gap. They consist of texts from Project Gutenberg adapted for learners with a vocabulary size of 4,000 word families, 6,000 word families and 8,000 word families. Each text is available at these three different levels. The goal is to have at least fifty such texts at each of the three different levels freely available. The adaptation is done using the BNC/COCA word family lists and the AntWordProfiler program. The article also discusses research that needs to be done on learning mid-frequency vocabulary and on creating and using mid-frequency readers

Mechanical Properties Of Individual Southern Pine Fibers. Part II. Comparison Of Earlywood And Latewood Fibers With Respect To Tree Height And Juvenility

This paper reports variations in mechanical properties of individual southern pine fibers and compares engineering properties of earlywood and latewood tracheids with respect to tree height and juvenility. Results indicate that latewood fibers exhibit greater strength and stiffness than earlywood fibers irrespective of tree height or juvenility. Average earlywood loblolly pine fibers had modulus of elasticity and ultimate tensile stress values of 14.8 GPa and 604 MPa, respectively. Corresponding latewood fibers had modulus of elasticity and ultimate tensile stress values that were, respectively, 33 and 73% higher. These differences are attributable to microfibril angles and pitting. Juvenility as defined by the mechanical properties of individual wood fibers is not a cylindrical cone surrounding the pith but appears to be biconical, tapering from the base to below the live crown and then again from the live crown to the apex