Application of the Kelly Criterion to Ornstein-Uhlenbeck Processes

In this paper, we study the Kelly criterion in the continuous time framework building on the work of E.O. Thorp and others. The existence of an optimal strategy is proven in a general setting and the corresponding optimal wealth process is found. A simple formula is provided for calculating the optimal portfolio for a set of price processes satisfying some simple conditions. Properties of the optimal investment strategy for assets governed by multiple Ornstein-Uhlenbeck processes are studied. The paper ends with a short discussion of the implications of these ideas for financial markets.Comment: presented at Complex'2009 (Shanghai, Feb. 23-25

TWO NEW PLOCENE SPECIES OF CYCLOSTEPHANOS (BACILLARIOPHYCEAE) WITH COMMENTS ON THE CLASSIFICATION OF THE FRESHWATER THALASSIOSIRACEAE 1

Two new species of the diatom genus Cyclostephanos Round are described from Pliocene fossil deposits in western North America. Cyclostephanos undatus is distinguished from other Cyclostephanos species by its tangentially undulate valve face; Cyclostephanos fenestratus is distinguished by its extremely shallow alveoli. This paper records previously unreported morphological detail of Cyclostephanos and speculates that structure of the punctum, labiate process and strutted process may enhance diagnosis of the freshwater genera of the Thalassiosiraceae Lebour emend. Hasle. Cyclostephanos undatus is similar to several Cyclotella species, but its external costae are raised and its alveolar morphology is similar to that of Cyclostephanos dubius (Fricke) Round. Cyclostephanos fenestratus is similar in external view to Stephanodiscus Ehrenb. However, the two species described here have flat cribra covering the mantle puncta and the labiate processes appear to lack external tubes, whereas Stephanodiscus species have domed mantle cribra and external tubes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65645/1/j.1529-8817.1986.tb04154.x.pd

Universal Rights and Wrongs

This paper argues for the important role of customers as a source of competitive advantage and firm growth, an issue which has been largely neglected in the resource-based view of the firm. It conceptualizes Penrose’s (1959) notion of an ‘inside track’ and illustrates how in-depth knowledge about established customers combines with joint problem-solving activities and the rapid assimilation of new and previously unexploited skills and resources. It is suggested that the inside track represents a distinct and perhaps underestimated way of generating rents and securing long-term growth. This also implies that the sources of sustainable competitive advantage in important respects can be sought in idiosyncratic interfirm relationships rather than within the firm itself

Family medicine in post-communist Europe needs a boost. Exploring the position of family medicine in healthcare systems of Central and Eastern Europe and Russia

<p>Abstract</p> <p>Background</p> <p>The countries of Central and Eastern Europe have experienced a lot of changes at the end of the 20th century, including changes in the health care systems and especially in primary care. The aim of this paper is to systematically assess the position of family medicine in these countries, using the same methodology within all the countries.</p> <p>Methods</p> <p>A key informants survey in 11 Central and Eastern European countries and Russia using a questionnaire developed on the basis of systematic literature review.</p> <p>Results</p> <p>Formally, family medicine is accepted as a specialty in all the countries, although the levels of its implementation vary across the countries and the differences are important. In most countries, solo practice is the most predominant organisational form of family medicine. Family medicine is just one of many medical specialties (e.g. paediatrics and gynaecology) in primary health care. Full introduction of family medicine was successful only in Estonia.</p> <p>Conclusions</p> <p>Some of the unification of the systems may have been the result of the EU request for adequate training that has pushed the policies towards higher standards of training for family medicine. The initial enthusiasm of implementing family medicine has decreased because there was no initiative that would support this movement. Internal and external stimuli might be needed to continue transition process.</p

The influence of using digital diagnostic information on orthodontic treatment planning - a pilot study

The purpose of this pilot study was to assess whether orthodontic treatment planning is reproducible when carried out using digital records compared with clinical examinations or using standard records. The study also assessed patients' opinion of face-to-face consultations and potential use of teleorthodontics. The study was designed as a prospective observational cross-sectional pilot study and carried out in a UK dental teaching hospital involving 27 subjects. Four consultant Orthodontists carried out treatment planning, firstly following a clinical examination, then using standard records, and then using digital records. Each subject completed a questionnaire. Cohen's kappa coefficient and Fleiss' kappa coefficient were used to assess intra-observer reproducibility and inter-observer reproducibility of treatment planning decisions, respectively. A change in the diagnostic information format affected treatment planning reproducibility for half of the observers. Inter-observer reproducibility was greater when using hard copy records in comparison to digital records. No subjects were unsatisfied with their face-to-face consultation

Ratings of age of acquisition of 299 words across 25 languages: Is there a cross-linguistic order of words?

We present a new set of subjective age-of-acquisition (AoA) ratings for 299 words (158 nouns, 141 verbs) in 25 languages from five language families (Afro-Asiatic: Semitic languages; Altaic: one Turkic language: Indo-European: Baltic, Celtic, Germanic, Hellenic, Slavic, and Romance languages; Niger-Congo: one Bantu language; Uralic: Finnic and Ugric languages). Adult native speakers reported the age at which they had learned each word. We present a comparison of the AoA ratings across all languages by contrasting them in pairs. This comparison shows a consistency in the orders of ratings across the 25 languages. The data were then analyzed (1) to ascertain how the demographic characteristics of the participants influenced AoA estimations and (2) to assess differences caused by the exact form of the target question (when did you learn vs. when do children learn this word); (3) to compare the ratings obtained in our study to those of previous studies; and (4) to assess the validity of our study by comparison with quasi-objective AoA norms derived from the MacArthur–Bates Communicative Development Inventories (MB-CDI). All 299 words were judged as being acquired early (mostly before the age of 6 years). AoA ratings were associated with the raters’ social or language status, but not with the raters’ age or education. Parents reported words as being learned earlier, and bilinguals reported learning them later. Estimations of the age at which children learn the words revealed significantly lower ratings of AoA. Finally, comparisons with previous AoA and MB-CDI norms support the validity of the present estimations. Our AoA ratings are available for research or other purposes