Weighted ancestors in suffix trees

The classical, ubiquitous, predecessor problem is to construct a data structure for a set of integers that supports fast predecessor queries. Its generalization to weighted trees, a.k.a. the weighted ancestor problem, has been extensively explored and successfully reduced to the predecessor problem. It is known that any solution for both problems with an input set from a polynomially bounded universe that preprocesses a weighted tree in O(n polylog(n)) space requires \Omega(loglogn) query time. Perhaps the most important and frequent application of the weighted ancestors problem is for suffix trees. It has been a long-standing open question whether the weighted ancestors problem has better bounds for suffix trees. We answer this question positively: we show that a suffix tree built for a text w[1..n] can be preprocessed using O(n) extra space, so that queries can be answered in O(1) time. Thus we improve the running times of several applications. Our improvement is based on a number of data structure tools and a periodicity-based insight into the combinatorial structure of a suffix tree.Comment: 27 pages, LNCS format. A condensed version will appear in ESA 201

Insiders\u27 Profits in the Australian Equities Market

In this paper we investigate if directors of Australian companies earn persistent profits on their reported trades, if these abnormal profits are significant enough to be mimicked by outsiders, and if these insider trades have an effect on returns of other investors. We find that insiders take advantage of their private information in stocks of larger corporations, but generally do not in medium and small capitalization firms, indicating that they insiders are attracted to the liquidity and a greater presence of uninformed traders in large stocks. Insiders appear able to determine the value of their information in by trading larger volume and larger portion of their holdings when they have access to valuable information. We find that outsiders can make profitable trades by following insider\u27s trades in large firms, but abnormal returns mimicking insiders in small and medium size firms are limited to insiders\u27 sell trades only, and otherwise result in losses for outsiders. Implications on market fairness and integrity are discussed and conclude that market quality can be improved with public access to good quality aggregated data on reported director insider trades

Prenatal Lead Exposure Risk Assessment by Vermont Maternity Care Providers

Introduction. One percent of women of childbearing age in the U.S. have blood lead levels ≥ 5 ug/dL, which are associated with maternal hypertension during pregnancy, neural tube and cardiac defects in infants, low birth weight, prematurity, and spontaneous abortion. It is unknown whether obstetrics providers in Vermont are screening their pregnant patients for lead levels and educating them on lead exposure risks. Objective. To gain an understanding of current lead screening practices in Vermont and issue recommendations for disseminating lead screening information. Methods. We developed and e-mailed a survey to practicing OB/GYN physicians, maternity care focused family medicine physicians, nurse midwives, and professional midwives. The survey assessed current screening practices for lead exposure in their pregnant patients, interest in receiving statewide guidelines, and guideline dissemination preferences. Results. Of the 41 respondents, 12% currently conduct risk assessments for lead exposure with all of their pregnant patients. Fifty four percent of maternity providers give all of their patients educational materials about lead exposure and risk of toxicity. Seventy one percent of maternity providers think that having guidelines provided by the Vermont Department of Health would encourage them to begin or continue lead exposure screening. The two preferred methods of communicating guidelines to physicians were grand rounds and email whereas non-physician providers preferred email and webinar. Discussion. The majority of pregnant patients in Vermont are not properly assessed or educated about lead risks. However, there is interest in having statewide standardized lead risk assessment guidelines, with dissemination preferences differing by provider type.https://scholarworks.uvm.edu/comphp_gallery/1248/thumbnail.jp

Erratum: “Evaluating computer‐aided detection algorithms”

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134826/1/mp5750.pd

Cross-Document Pattern Matching

We study a new variant of the string matching problem called cross-document string matching, which is the problem of indexing a collection of documents to support an efficient search for a pattern in a selected document, where the pattern itself is a substring of another document. Several variants of this problem are considered, and efficient linear-space solutions are proposed with query time bounds that either do not depend at all on the pattern size or depend on it in a very limited way (doubly logarithmic). As a side result, we propose an improved solution to the weighted level ancestor problem

Insiders’ profits in the Australian Equities Market

In this paper we investigate if directors of Australian companies earn persistent profits on their reported trades, if these abnormal profits are significant enough to be mimicked by outsiders, and if these insider trades have an effect on returns of other investors. We find that insiders take advantage of their private information in stocks of larger corporations, but generally do not in medium and small capitalization firms, indicating that they insiders are attracted to the liquidity and a greater presence of uninformed traders in large stocks. Insiders appear able to determine the value of their information in by trading larger volume and larger portion of their holdings when they have access to valuable information. We find that outsiders can make profitable trades by following insider’s trades in large firms, but abnormal returns mimicking insiders in small and medium size firms are limited to insiders’ sell trades only, and otherwise result in losses for outsiders. Implications on market fairness and integrity are discussed and conclude that market quality can be improved with public access to good quality aggregated data on reported director insider trade

Professional boundaries: crossing a line or entering the shadows?

This article explores the professional boundaries guidance for social workers. It presents research findings from the formal literature, from agency codes of practice, from telephone interviews with regulatory and professional bodies and from an exercise using ‘snowballing techniques’ in which informants responded to brief scenarios illustrating boundary dilemmas. The findings suggest that formal research plays little part in the guidance that individuals use to help them determine professional boundaries. Similarly, only 10–15 per cent of informants made regular reference to regulatory and professional codes of practice, with an even smaller percentage quoting specific sections from these codes. A slightly larger group (15–20 per cent) made fairly regular reference to their agency's policy documents. However, a clear majority relied on their own sense of what is appropriate or inappropriate, and made their judgements with no reference to any formal guidance. Agency guidance tended to ignore the ambiguous areas of practice and seemed to act as an insurance policy, brought out and dusted off when something goes awry. The authors caution against ever-increasing bullet points of advice and prescription, and advance a notion of ethical engagement in which professionals exercise their ethical senses through regular discussion of professional boundary dilemmas

Knowledge Exchange Through Science Diplomacy to Assist Disaster Risk Reduction. Progress in Disaster Science

This paper analyses science diplomacy efforts to reduce disaster risks and proposes establishing national knowledge exchange centers (KECs) to help individual states adhere to their Sendai Framework goals. KECs are considered to be interconnected globally and work together to promote resilience efforts by facilitating sharing of information and strategies in risk monitoring, assessment, and ultimately reduction across the globe. KECs can provide high-quality scientific evidence for informed decisionmaking along with a component related to disaster science media to ensure that appropriate knowledge reaches a variety of people who need it in different forms tailored for them. KECs can promote transdisciplinary education in disaster-related science diplomacy (i.e., disaster diplomacy). The United Nations Office for Disaster Risk Reduction (UNDRR) and the International Science Council (ISC) can provide assistance to KECs through UNDRR National Platforms and ISC Members