The estimation of statistical coefficients from samples

Statistics, it has been said, is the reduction of data. This definition fails, however, to bring out one of the most important and interesting aspects of modern statistical theory - the making of estimates. Let us consider a typical example. An investigator collects a body of data, consisting, say, of the heights, or other attribute, of some members of a community. He calculates a few quantities - such as a mean, a measure of dispersion, perhaps one of skewness - which enable him to apprehend the properties of the assemblage of figures. This is the reduction of data. But now curiosity or practical need poses a new question. What can be said regarding the heights of all the members of the community - not merely of those in respect of whom information is tabulated? Of course, nothing can be stated with certainty. The heights of the members who were measured may vary widely from those of the others. Nevertheless, intuition, or experience, suggests that at least a guess might be hazarded. One suspects, too, that in some instances a better guess is justified than in others. Can one, then, measure in some fashion the reliability of a guess? Questions such as these are the subject-matter of the Theory of Estimation.This theory, as our example indicates, has nothing in common with the deductive problems frequently encountered.in Pure Mathematics, such as the deduction of a particular geometrical theorem, given a few general axioms. On the contrary, Estimation is concerned with the realm of induction; with passing from the particular to the general; with the making of inferences regarding a population from the data of a sample thereof. By their nature, these inferences are uncertain. Perhaps it is the insufficient appreciation of this which has led to the well-known criticism that statistics "can be made to prove anything." It would be fairer to say that statistics proves nothing - but that it may suggest a great deal

Pendred's syndrome in South African Bantu brothers

No Abstract

Using LiDAR to assess the effect of fire and floods on upland peat bogs, Waterfall Gully, Mount Lofty Ranges, South Australia

A flood exceeding the 100 year average recurrence interval in November 2005 led to the failure of an upland peat bog in Waterfall Gully. The area is prone to severe bushfire and flood events and the control dam at the base of First Falls was filled with sediment sourced from Wilson Bog. A resistant quartzite bar at Fourth Falls has formed a natural constriction point against which burnt logs and debris have collected following previous fire events forming a natural dam resulting in sediment/peat accumulation upstream. The failure of the bog was inevitable as the vegetative material in the log-jam progressively weakened and rotted. Intense flooding triggered the failure but it was augmented by the build up of a critical mass of sediment upstream of the restriction point. The downstream force of the flood waters and the weight of the saturated bog sediments was enough to overcome the basal frictional forces resulting in slumping and headward erosion. LiDAR data clearly shows an erosion channel scoured out by the flood. Approximately 5000 m3 of sediment (-10,100 tonnes) was washed downstream. LiDAR coupled with a tri-spectral scanner has the capacity to identify other upland peat bogs due to their high NDVI value and assess their stability on steep slopes or narrow valleys. Fire is another risk to the stability of these bogs as it has the potential to remove binding vegetation and expose unconsolidated sediments to erosion during subsequent rain events. Groundsurface and vegetation surface DEM\u27s generated from LiDAR combined with NDVI maps derived from a tri-spectral scanner provide an ideal tool to monitor and assess the risk of slumping in other upland peat bogs

Forecasting Energy Demand in Large Commercial Buildings Using Support Vector Machine Regression

As our society gains a better understanding of how humans have negatively impacted the environment, research related to reducing carbon emissions and overall energy consumption has become increasingly important. One of the simplest ways to reduce energy usage is by making current buildings less wasteful. By improving energy efficiency, this method of lowering our carbon footprint is particularly worthwhile because it reduces energy costs of operating the building, unlike many environmental initiatives that require large monetary investments. In order to improve the efficiency of the heating, ventilation, and air conditioning (HVAC) system of a Manhattan skyscraper, 345 Park Avenue, a predictive computer model was designed to forecast the amount of energy the building will consume. This model uses Support Vector Machine Regression (SVMR), a method that builds a regression based purely on historical data of the building, requiring no knowledge of its size, heating and cooling methods, or any other physical properties. SVMR employs time-delay coordinates as a representation of the past to create the feature vectors for SVM training. This pure dependence on historical data makes the model very easily applicable to different types of buildings with few model adjustments. The SVM regression model was built to predict a week of future energy usage based on past energy, temperature, and dew point temperature data

Preliminary needs assessment of mobile technology use for healthcare among homeless veterans

Background. Homeless veterans have complex healthcare needs, but experience many barriers to treatment engagement. While information technologies (IT), especially mobile phones, are used to engage patients in care, little is known about homeless veterans\u27 IT use. This study examines homeless veterans\u27 access to and use of IT, attitudes toward health-related IT use, and barriers to IT in the context of homelessness. Methods. Qualitative interviews were conducted with 30 homeless veterans in different housing programs in Boston, MA, ranging from emergency shelters to supportive transitional housing that allow stays of up to 2 years. Interviews were conducted in person, audio recorded and then transcribed. Three researchers coded transcripts. Inductive thematic analysis was used. Results. Most participants (90%) had a mobile phone and were receptive to IT use for health-related communications. A common difficulty communicating with providers was the lack of a stable mailing address. Some participants were using mobile phones to stay in touch with providers. Participants felt mobile-phone calls or text messages could be used to remind patients of appointments, prescription refills, medication taking, and returning for laboratory results. Mobile phone text messaging was seen as convenient, and helped participants stay organized because necessary information was saved in text messages. Some reported concerns about the costs associated with mobile phone use (calls and texting), the potential to be annoyed by too many text messages, and not knowing how to use text messaging. Conclusion. Homeless veterans use IT and welcome its use for health-related purposes. Technology-assisted outreach among this population may lead to improved engagement in care

Improving Efficiency and Reliability of Building Systems Using Machine Learning and Automated Online Evaluation

A high percentage of newly-constructed commercial office buildings experience energy consumption that exceeds specifications and system failures after being put into use. This problem is even worse for older buildings. We present a new approach, 'predictive building energy optimization', which uses machine learning (ML) and automated online evaluation of historical and real-time building data to improve efficiency and reliability of building operations without requiring large amounts of additional capital investment. Our ML approach uses a predictive model to generate accurate energy demand forecasts and automated analyses that can guide optimization of building operations. In parallel, an automated online evaluation system monitors efficiency at multiple stages in the system workflow and provides building operators with continuous feedback. We implemented a prototype of this application in a large commercial building in Manhattan. Our predictive machine learning model applies Support Vector Regression (SVR) to the building's historical energy use and temperature and wet-bulb humidity data from the building's interior and exterior in order to model performance for each day. This predictive model closely approximates actual energy usage values, with some seasonal and occupant-specific variability, and the dependence of the data on day-of-the-week makes the model easily applicable to different types of buildings with minimal adjustment. In parallel, an automated online evaluator monitors the building's internal and external conditions, control actions and the results of those actions. Intelligent real-time data quality analysis components quickly detect anomalies and automatically transmit feedback to building management, who can then take necessary preventive or corrective actions. Our experiments show that this evaluator is responsive and effective in further ensuring reliable and energyefficient operation of building systems

Four award-winning novellas

Kao prethodnica onome što će od 1955. godine postati „Nagradni konkurs Saveza jevrejskih opština Jugoslavije“ (od 2006. godine - Saveza JO Srbije) svakako je vredno pomenuti jednu inicijativu pokrenutu još 1935. godine, od strane aktivista tadašnje Jevrejske čitaonice u Beogradu, koji su te godine raspisali nagradni konkurs „za neobjavljenu originalnu pripovetku sa jevrejskom tematikom sa ciljem podstreka za takmičenje jevrejskih omladinaca u duhovnom radu, te sa pravom učešća omladinaca Jevreja iz naših krajeva, do svoje 25 godine starosti, bez obzira na njihove školske kvalifikacije“. Tadašnji žiri činili su urednik Politike Živko Miličević, književnik dr Isak Samokovlija i lekar Bukić Pijade. Sledeće, 1935. godine Jevrejska čitaonica izdala je knjigu „Četiri nagrađene novele“ u kojoj su objavljeni nagrađeni rukopisi sa tog nagradnog konkursa. Reč je o novelama „Komadić hleba s medom“ - Julije Špicer, „Ludi Bohor“ - Solomona Fincija, „Najsrećniji dan rabi Rafaela - Jahiela Katana, i „Tiju Hajim“ - Leona M. Išaha.As an announcement to what will become the "Award competition of the Federation of Jewish communities of Yugoslavia" from 1955 (since 2006 - the Federation of JC Serbia), it is certainly worth mentioning an initiative launched in 1935, by the activists of the then Jewish reading room in Belgrade, which that year announced a prize competition "for an unpublished original short story with a Jewish theme to encourage the competition of Jewish youth in spiritual work, and with the right of participation of Jewish youth from our regions, up to the age of 25, regardless of their school qualifications". The then jury consisted of the editor of Politika Živko Miličević, the writer Dr. Isak Samokovlija and the doctor Bukić Pijade. The following year, in 1935, the Jevrejska čitaonica published the book "Four award-winning novellas" in which the prize-winning manuscripts from that competition were published. We are talking about the novels "A Piece of Bread with Honey" by Julija Špicer, "Crazy Bohor" by Solomon Finci, "The Happiest Day of Rabi Rafael - by Jahiel Katan, and "Tija Hajim" - by Leon M. Išah.Sadržaj s naslovne strane (contents from the front page): Komadić hleba s medom / Julije Špicer; Ludi Bohor / Solomon Finci; Najsrećniji dan Rabi Rafaela / Jahiel Katan; Tiju Hajim / Leon M. Išah

Long-term trends in the longevity of scientific elites: evidence from the British and the Russian academies of science.

National science academies represent intellectual elites and vanguard groups in the achievement of longevity. We estimated life expectancy (LE) at age 50 of members of the British Royal Society (RS) for the years 1670-2007 and of members of the Russian Academy of Sciences (RAS) for the years 1750-2006. The longevity of academicians was higher than that of their corresponding national populations, with the gap widening from the 1950s. Since the 1980s, LE in the RS has been higher than the maximum LE among all high-income countries. In each period, LE in the RS was greater than in the RAS, although since the 1950s it has risen in parallel in the two academies. This steep increase shared by academicians in Britain and Russia suggests that general populations have the potential for a substantial increase in survival to high ages

HCN(1-0) enhancement in the bar of NGC 2903

We have mapped the \hcn emission from two spiral galaxies, NGC2903 and NGC3504 to study the gas properties in the bars. The HCN(1-0) emission is detected in the center and along the bar of NGC2903. The line ratio HCN(1-0)/CO(1-0) ranges from 0.07 to 0.12 with the lowest value in the center. The enhancement of HCN(1-0) emission along the bar indicates a higher fraction of dense molecular gas in the bar than at the center. The mass of dense molecular gas in the center (2.2x 10^7 Msun) is about 6 times lower than that in the bar (1.2x 10^8 Msun). The total star formation rate (SFR) is estimated to be 1.4 Msun/yr, where the SFR at the center is 1.9 times higher than that in the bar. The time scale of consumption of the dense molecular gas in the center is about 3x 10^7 yr which is much shorter than that in the bar of about 2 to 10 x 10^8 yr. The dynamical time scale of inflow of the gas from the bar to the center is shorter than the consumption time scale in the bar, which suggests that the star formation (SF) activity at the center is not deprived of fuel. In the bar, the fraction of dense molecular gas mass relative to the total molecular gas mass is twice as high along the leading edge than along the central axis of the bar. The \hcn emission has a large velocity dispersion in the bar, which can be attributed partially to the streaming motions indicative of shocks along the bar. In NGC3504, the HCN(2-0) emission is detected only at the center. The fraction of dense molecular gas mass in the center is about 15%. Comparison of the SFR with the predictions from numerical simulations suggest that NGC2903 harbors a young type B bar with a strong inflow of gas toward the center whereas NGC3504 has an older bar and has already passed the phase of inflow of gas toward the center.Comment: Acceoted for publication in A&A, 12 figure

Imaging linear polarimetry using a single ferroelectric liquid crystal modulator

International audienceIn the field of polarimetry, ferroelectric liquid crystal cells are mostly used as bistable polarization rotators suitable to analyze crossed polarizations. This paper shows that, provided such a cell is used at its nominal wavelength and correctly driven, its behavior is close to that of a tunable half-wave plate, and it can be used with much benefit in lightweight imaging polarimetric setups. A partial Stokes polarimeter using a single digital video camera and a single ferroelectric liquid crystal modulator is designed and implemented for linear polarization analysis. Polarization azimuthal angle and degree of linear polarization are available at 150 frames per second with a good accuracy