Algorithmic Identification of Probabilities

TThe problem is to identify a probability associated with a set of natural numbers, given an infinite data sequence of elements from the set. If the given sequence is drawn i.i.d. and the probability mass function involved (the target) belongs to a computably enumerable (c.e.) or co-computably enumerable (co-c.e.) set of computable probability mass functions, then there is an algorithm to almost surely identify the target in the limit. The technical tool is the strong law of large numbers. If the set is finite and the elements of the sequence are dependent while the sequence is typical in the sense of Martin-L\"of for at least one measure belonging to a c.e. or co-c.e. set of computable measures, then there is an algorithm to identify in the limit a computable measure for which the sequence is typical (there may be more than one such measure). The technical tool is the theory of Kolmogorov complexity. We give the algorithms and consider the associated predictions.Comment: 19 pages LaTeX.Corrected errors and rewrote the entire paper. arXiv admin note: text overlap with arXiv:1208.500

Universal generalization and universal inter-item confusability

We argue that confusability between items should be distinguished from generalization between items. Shepard's data concern confusability, but the theories proposed by Shepard and by Tenenbaum & Griffiths concern generalization, indicating a gap between theory and data. We consider the empirical and theoretical work involved in bridging this gap

The impact of active workstations on workplace productivity and performance: a systematic review

Active workstations have been recommended for reducing sedentary behavior in the workplace. It is important to understand if the use of these workstations has an impact on worker productivity. The aim of this systematic review was to examine the effect of active workstations on workplace productivity and performance. A total of 3303 articles were initially identified by a systematic search and seven articles met eligibility criteria for inclusion. A quality appraisal was conducted to assess risk of bias, confounding, internal and external validity, and reporting. Most of the studies reported cognitive performance as opposed to productivity. Five studies assessed cognitive performance during use of an active workstation, usually in a single session. Sit-stand desks had no detrimental effect on performance, however, some studies with treadmill and cycling workstations identified potential decreases in performance. Many of the studies lacked the power required to achieve statistical significance. Three studies assessed workplace productivity after prolonged use of an active workstation for between 12 and 52 weeks. These studies reported no significant effect on productivity. Active workstations do not appear to decrease workplace performance

Who uses foodbanks and why? Exploring the impact of financial strain and adverse life events on food insecurity

Background Rising use of foodbanks highlights food insecurity in the UK. Adverse life events (e.g. unemployment, benefit delays or sanctions) and financial strains are thought to be the drivers of foodbank use. This research aimed to explore who uses foodbanks, and factors associated with increased food insecurity. Methods We surveyed those seeking help from front line crisis providers from foodbanks (N = 270) and a comparison group from Advice Centres (ACs) (N = 245) in relation to demographics, adverse life events, financial strain and household food security. Results About 55.9% of foodbank users were women and the majority were in receipt of benefits (64.8%). Benefit delays (31.9%), changes (11.1%) and low income (19.6%) were the most common reasons given for referral. Compared to AC users, there were more foodbank users who were single men without children, unemployed, currently homeless, experiencing more financial strain and adverse life events (P = 0.001). Food insecurity was high in both populations, and more severe if they also reported financial strain and adverse life events. Conclusions Benefit-related problems appear to be a key reason for foodbank referral. By comparison with other disadvantaged groups, foodbank users experienced more financial strain, adverse life events, both increased the severity of food insecurity

Young people's use of NHS Direct: a national study of symptoms and outcome of calls for children aged 0-15

Objectives National Health Service (NHS) Direct provides 24/7 expert telephone-based healthcare information and advice to the public in England. However, limited research has explored the reasons to why calls are made on behalf of young people, as such this study aimed to examine call rate (CR) patterns in younger people to enable a better understanding of the needs of this population in England. Setting NHS Direct, England, UK. Participants and methods CRs (expressed as calls/100 persons/annum) were calculated for all calls (N=358 503) made to NHS Direct by, or on behalf of, children aged 0–15 during the combined four ‘1-month’ periods within a year (July 2010, October 2010, January 2011 and April 2011). χ² Analysis was used to determine the differences between symptom, outcome and date/time of call. Results For infants aged <1, highest CRs were found for ‘crying’ for male (n=14, 440, CR=13.61) and female (n=13 654, CR=13.46) babies, which is used as a universal assessment applied to all babies. High CRs were also found for symptoms relating to ‘skin/hair/nails’ and ‘colds/flu/sickness’ for all age groups, whereby NHS Direct was able to support patients to self-manage and provide health information for these symptoms for 59.7% and 51.4% of all cases, respectively. Variations in CRs were found for time and age, with highest peaks found for children aged 4–15 in the 15:00–23:00 period and in children aged <1 in the 7:00–15:00 period. Conclusions This is the first study to examine the symptoms and outcome of calls made to NHS Direct for and on behalf of young children. The findings revealed how NHS Direct has supported a range of symptoms through the provision of health information and self-care support which provides important information about service planning and support for similar telephone-based services

The impact of location of the uptake of telephone based healthcare

Telephone healthcare systems have been put forward as a key strategy to overcome geographical disadvantage, however, evidence has suggested that usage decreases with increasing rurality. This research aimed to identify geographical high and low areas of usage of NHS Direct, a leading telephone healthcare provider worldwide to determine if usage is influenced by rurality. National call data was collected (January, 2011) from the NHS Direct Clinical Assessment System for all 0845 4647 calls in England, UK (N=360,137). Data extracted for analysis included; unit postcode of patient, type of call, date of call, time of call and final disposition. Calls were mapped using GIS mapping software using full postcode, aggregated by population estimate by local authority to determine confidence intervals across two thresholds by call rate. Uptake rate Output Area Classification (OAC) group profiles was performed using the chi-square goodness of fit. The majority of calls were ‘symptomatic’ (N=280,055; 74.8%) i.e. calls that were triaged by an expert nurse, with the remaining 25.2% of calls health/ medicine information only (N=94,430). NHS Direct were able to manage through self-care advice and health information 43.5 of all calls made (N=99,367) with no onward referral needed. Geographical pattern of calls were highest for more urbanised areas with significant higher call usage found in larger cities. Lower observed usage was found in areas that are more rural of which were characterised by above average older populations. This was supported by geo-segmentation, which highlighted that rural and older communities had the lowest expected uptake rate. There is a variation of usage of NHS Direct relating to rurality, which suggests that this type of service has not been successful in reducing accessible barriers. However, geographical variations are likely to be influenced by age. There is a need for exploratory to determine the underlying factors that contribute to variation in uptake of these services particularly older people who reside in rural communities. This will have worldwide implications as to how telephone based healthcare is introduced