Critical reflexivity in financial markets: a Hawkes process analysis

We model the arrival of mid-price changes in the E-Mini S&P futures contract as a self-exciting Hawkes process. Using several estimation methods, we find that the Hawkes kernel is power-law with a decay exponent close to -1.15 at short times, less than approximately 10^3 seconds, and crosses over to a second power-law regime with a larger decay exponent of approximately -1.45 for longer times scales in the range [10^3, 10^6] seconds. More importantly, we find that the Hawkes kernel integrates to unity independently of the analysed period, from 1998 to 2011. This suggests that markets are and have always been close to criticality, challenging a recent study which indicates that reflexivity (endogeneity) has increased in recent years as a result of increased automation of trading. However, we note that the scale over which market events are correlated has decreased steadily over time with the emergence of higher frequency trading.Comment: 9 pages, 6 figures. Some clarification and correction made to section II, minor alterations elsewher

Accelerating Positive Change In Electronic Recrds Management - An Emprical Toolkit Of Solutions

The AC+erm project aims to investigate and critically explore issues and practical strategies for accelerating positive change in electronic records management. The project’s focus is on designing an organisational-centred architecture from three perspectives: people, process and technology. This paper introduces the project, describes the methodology (a systematic literature review, e-Delphi studies and colloquia) and presents solutions for improving ERM developed from the people and process e-Delphi responses. ERM is particularly challenging and the solutions offered by the Delphi participants are numerous, and range in scale and complexity. The only firm conclusion that one can draw is that the majority of the solutions are people-focussed ones. The Cynefin framework is introduced as one approach for providing a conceptual overview to our findings on ERM. The sample solutions presented in this paper provide a toolkit of ‘probes’ and ‘interventions’ for practical application in organisations

Is auditory discrimination mature by middle childhood? A study using time-frequency analysis of mismatch responses from 7 years to adulthood

Behavioural and electrophysiological studies give differing impressions of when auditory discrimination is mature. Ability to discriminate frequency and speech contrasts reaches adult levels only around 12 years of age, yet an electrophysiological index of auditory discrimination, the mismatch negativity (MMN), is reported to be as large in children as in adults. Auditory ERPs were measured in 30 children (7 to 12 years), 23 teenagers (13 to 16 years) and 32 adults (35 to 56 years) in an oddball paradigm with tone or syllable stimuli. For each stimulus type, a standard stimulus (1000 Hz tone or syllable [ba]) occurred on 70% of trials, and one of two deviants (1030 or 1200 Hz tone, or syllables [da] or [bi]) equiprobably on the remaining trials. For the traditional MMN interval of 100–250 ms post-onset, size of mismatch responses increased with age, whereas the opposite trend was seen for an interval from 300 to 550 ms post-onset, corresponding to the late discriminative negativity (LDN). Time-frequency analysis of single trials revealed that the MMN resulted from phase-synchronization of oscillations in the theta (4–7 Hz) range, with greater synchronization in adults than children. Furthermore, the amount of synchronization was significantly correlated with frequency discrimination threshold. These results show that neurophysiological processes underlying auditory discrimination continue to develop through childhood and adolescence. Previous reports of adult-like MMN amplitudes in children may be artefactual results of using peak measurements when comparing groups that differ in variance

The welfare consequences and efficacy of training pet dogs with remote electronic training collars in comparison to reward based training

This study investigated the welfare consequences of training dogs in the field with manually operated electronic devices (e-collars). Following a preliminary study on 9 dogs, 63 pet dogs referred for recall related problems were assigned to one of three Groups: Treatment Group A were trained by industry approved trainers using e-collars; Control Group B trained by the same trainers but without use of e-collars; and Group C trained by members of the Association of Pet Dog Trainers, UK again without e-collar stimulation (n = 21 for each Group). Dogs received two 15 minute training sessions per day for 4-5 days. Training sessions were recorded on video for behavioural analysis. Saliva and urine were collected to assay for cortisol over the training period. During preliminary studies there were negative changes in dogs' behaviour on application of electric stimuli, and elevated cortisol post-stimulation. These dogs had generally experienced high intensity stim uli without pre-warning cues during training. In contrast, in the subsequent larger, controlled study, trainers used lower settings with a pre-warning function and behavioural responses were less marked. Nevertheless, Group A dogs spent significantly more time tense, yawned more often and engaged in less environmental interaction than Group C dogs. There was no difference in urinary corticosteroids between Groups. Salivary cortisol in Group A dogs was not significantly different from that in Group B or Group C, though Group C dogs showed higher measures than Group B throughout sampling. Following training 92% of owners reported improvements in their dog's referred behaviour, and there was no significant difference in reported efficacy across Groups. Owners of dogs trained using e-collars were less confident of applying the training approach demonstrated. These findings suggest that there is no consistent benefit to be gained from e-collar training but greater welfare concer! ns compared with positive reward based training

CFT & people with intellectual disabilities

Purpose The purpose of this paper is to assess the effects of compassion-focussed therapy (CFT) on anxiety in a small sample of adults with intellectual disability. Design/methodology/approach A mixed-methods design was employed. Participants (n=3) completed questionnaire measures of anxiety and self-compassion on three occasions: pre-intervention, post-intervention and, at three months follow-up. Post-intervention, they also took part in recorded interviews that were analysed using interpretive phenomenological analysis. Findings were then synthesised to develop a comprehensive understanding of their overall experience. Findings Final data synthesis revealed five themes: participant anxiety decreased (reliable for all participants); the faulty self; improved positive compassionate attitudes; increased sense of common humanity; and mindful distraction techniques. Research limitations/implications This research paper offers in-depth analysis of three participants’ experiences rather than reporting in less detail about a larger number of participants. The self-compassion scale required considerable support and reasonable adaptation to be used with these clients. Originality/value Only two other studies have explored the use of CFT with people with intellectual disabilities

Mismatch Response to Polysyllabic Nonwords: A Neurophysiological Signature of Language Learning Capacity

Background: The ability to repeat polysyllabic nonwords such as ‘‘blonterstaping’’ has frequently been shown to correlate with language learning ability but it is not clear why such a correlation should exist. Three alternative explanations have been offered, stated in terms of differences in: (a) perceptual ability; (b) efficiency of phonological loop functioning; (c) preexisting vocabulary knowledge and/or articulatory skills. In the present study, we used event-related potentials to assess the contributions from these three factors to explaining individual variation in nonword repetition ability. Methodology/Principal Findings: 59 adults who were subdivided according to whether they were good or poor nonwordrepeaters participated. Electrophysiologically measured mismatch responses were recorded to changes in consonants as participants passively listened to a repeating four syllable CV-string. The consonant change could occur in one of four positions along the CV-string and we predicted that: (a) if nonword repetition depended purely on auditory discrimination ability, then reduced mismatch responses to all four consonant changes would be observed in the poor nonword-repeaters, (b) if it depended on encoding or decay of information in a capacity-limited phonological store, then a position specific decrease in mismatch response would be observed, (c) if neither cognitive capacity was involved, then the two groups of participants would provide equivalent mismatch responses. Consistent with our second hypothesis, a position specific difference located on the third syllable was observed in the late discriminative negativity (LDN) window (230–630 ms postsyllable onset). Conclusions/Significance: Our data thus confirm that people who are poorer at nonword repetition are less efficient in early processing of polysyllabic speech materials, but this impairment is not attributable to deficits in low level auditory discrimination. We conclude by discussing the significance of the observed relationship between LDN amplitude and nonword repetition ability and describe how this relatively little understood ERP component provides a biological window onto processes required for successful language learning

Remineralising effects of fluoride varnishes containing calcium phosphate on artificial root caries lesions with adjunctive application of proanthocyanidin

Objectives: To evaluate the remineralising effects of fluoride (F) varnishes containing bioavailable calcium-phosphate compound (Ca-P) based remineralisation systems and 5000 ppm F toothpaste (FTP) on root caries lesions (RCLs) and the potential effects of proanthocyanidin (PA) for the treatments of RCLs when used as an adjunct to F regimens. Methods: Demineralised root dentine and a pH-cycling model were used to mimic RCLs and the oral environment. Remineralising effects of MI VarnishTM (MIV) containing casein phosphopeptide–amorphous calcium phosphate (CPP-ACP) and Clinpro™ White Varnish (CPWV) containing tri-calcium phosphate (TCP) along with FTP and PA were evaluated regarding the birefringence, elemental composition, mechanical properties and mineral density of remineralised dentine with DuraphatTM as a comparison. Results: MIV, CPWV and DuraphatTM promoted the incorporation of F into RCLs and increased mineral density but did not change microhardness of root dentine significantly. Surface microhardness increased significantly when MIV or CPWV was used with 5000 ppm FTP. Application of PA with F regimens significantly increased subsurface mineral density. When PA was applied with MIV or CPWV along with FTP, the highest ion uptake and relative mineral gain (%ΔZ) was achieved, and significant increase of microhardness was up to 30 μm depth. Generally, MIV was associated with a higher mineral content gain than CPWV. Significance: Treatment of carious root surfaces remains challenging due to the complex pathological processes and difficulty in restoring the highly organised structure of root dentine. Treatment strategies targeting both remineralisation and preservation of the dentinal organic matrix have the potential to improve the fluoride-mediated remineralisation approaches

Crocodiles and grey nomads: a deadly combination?

Increasing numbers of retirees seek individual, extended, unstructured activities in remote, non-commercial locations. Travel is predominantly by self-drive 4WD vehicle towing a caravan/campervan. These ‘grey nomads’ often prefer remote bush camping sites/caravan parks to commercial resorts. The tropics – a popular destination – are inhabited by Australia’s only large semi-terrestrial carnivore, the estuarine crocodile Crocodylus porosus. Conservation programmes of recent decades have resulted in a substantial increase in numbers. With naive grey nomads increasingly encroaching on crocodile territory, attacks are expected to increase. Review of conservation programmes to incorporate awareness education targeting grey nomads is therefore required