12 research outputs found
Self-Attentive hawkes process
Capturing the occurrence dynamics is crucial to predicting which type of events will happen next and when. A common method to do this is through Hawkes processes. To enhance their capacity, recurrent neural networks (RNNs) have been incorporated due to RNNs successes in processing sequential data such as languages. Recent evidence suggests that self-Attention is more competent than RNNs in dealing with languages. However, we are unaware of the effectiveness of self-Attention in the context of Hawkes processes. This study aims to fill the gap by designing a self-Attentive Hawkes process (SAHP). SAHP employs self-Attention to summarise the influence of history events and compute the probability of the next event. One deficit of the conventional selfattention, when applied to event sequences, is that its positional encoding only considers the order of a sequence ignoring the time intervals between events. To overcome this deficit, we modify its encoding by translating time intervals into phase shifts of sinusoidal functions. Experiments on goodness-of-fit and prediction tasks show the improved capability of SAHP. Furthermore, SAHP is more interpretable than RNN-based counterparts because the learnt attention weights reveal contributions of one event type to the happening of another type. To the best of our knowledge, this is the first work that studies the effectiveness of self-Attention in Hawkes processes
A comparison between low-dose (1 mu g), standard-dose (250 mu g) ACTH stimulation tests and insulin tolerance test in the evaluation of hypothalamo-pituitary-adrenal axis in primary fibromyalgia syndrome
Objective: Primary fibromyalgia syndrome (PFS) is a nonarticular rheumatological syndrome characterized by disturbances in the hypothalamo-pituitary-adrenal (HPA) axis. The site of the defect in the HPA axis is a matter of debate. Our aim was to evaluate the HPA axis by the insulin-tolerance test (ITT), standard dose (250 mug) ACTH test (SDT) and low dose (1 mug) ACTH test (LDT) in patients with PFS
Traumatic spinal cord injuries in Turkey: a nation-wide epidemiological study
Study design: An epidemiological study conducted all over the country
Translation and validation of the Turkish version of the Ankylosing Spondylitis Quality of Life (ASQOL) questionnaire
WOS: 000325962100002PubMed ID: 23765201The Ankylosing Spondylitis Quality of Life (ASQoL) questionnaire is a disease-specific measure of needs-based quality of life developed in the UK and the Netherlands. This study describes translation, validation, and reliability of the scale into Turkish population. The ASQoL was translated into Turkish using the dual-panel process. Content validity was assessed via cognitive debriefing interviews with ankylosing spondylitis (AS) patients. Patients with AS according to modified New York criteria were recruited into the study from 12 hospitals of all part of Turkey. Psychometric and scaling properties were assessed via a two administration survey involving the ASQoL, the Nottingham Health Profile (NHP), Bath AS Functional Index (BASFI), and Bath AS Disease Activity Index (BASDAI). Classical psychometrics assessed reliability, convergent validity (correlation of ASQoL with NHP, BASFI, and BASDAI) and discriminative validity (correlation of ASQoL with perceived AS-severity and general health). Cognitive debriefing showed the new Turkish ASQoL to be clear, relevant, and comprehensive. Completed survey questionnaires were received from 277 AS patients (80 % Male, mean age 42.2/SD 11.6, mean AS duration 9.4 years/SD 9.4). Test-retest reliability was excellent (0.96), indicating low random measurement error for the scale. Correlations of ASQoL with NHP sections were low to moderate (NHP Sleep 0.34; NHP Emotional Reactions 0.83) suggesting the measures assess related but distinct constructs. The measure was able to discriminate between patients based on their perceived disease severity (p < 0.0001) and self-reported general health (p < 0.0001). The Turkish version of ASQoL has good reliability and validity properties. It is practical and useful scale to assess the quality of life in AS patients in Turkish population
The relation between tooth loss and bone mass in postmenopausal osteoporotic women in Turkey: a multicenter study
WOS: 000180078100008PubMed ID: 12491093The purpose of this study was to investigate the associations of tooth loss with skeletal bone mass, years since menopause, educational level, current smoking status, dietary calcium intake, and number of pregnancies in postmenopausal osteoporotic women in Turkey. The study population consisted of 1171 postmenopausal women aged 40-86 years (mean age, 61.19 +/- 7.28 years). A detailed history was obtained from all women, including relevant lifestyle parameters, risk factors, and measurements of weight and height. Women were separated into three groups according to the number of teeth remaining as group 1 (edentulous, 457 women), group 2 (10 or fewer teeth, 232 women), and group 3 (more than 10 teeth remaining, 482 women). There was no significant difference among the three groups in mean age and menopausal age (P < 0.05). Body mass index of group 1 was significantly higher than that of group 2 (P < 0.01). Educational level was significantly different between three groups: groups 1 and 2 (P < 0.001), groups 1 and 3 (P < 0.0001), and groups 2 and 3 (P < 0.001). Educational level was lowest in group 1 and highest in group 3. Despite a low ratio of cigarette smoking in general, a smoking habit was most prevalent in group 3 and least in group 2. The ratio of women receiving adequate calcium was significantly lower in group 1 than in other groups (P < 0.001); mean calcium intake was similar in all groups. The number of pregnancies was significantly higher in group 1 than in other groups (P < 0.001). Lumbar bone mineral density (BMD) of group 1 was significantly lower than that of groups 2 and 3 (P < 0.001). Although no significant difference was found between groups 1 and 3, femoral neck BMD of group 2 was less than in others, and differences between groups 1 and 2 and between groups 2 and 3 (P < 0.001) were significant. Lumbar bone mineral content (BMC) of group 1 was significantly lower than that of groups 2 and 3 (P < 0.001), and lumbar BMC in group 2 was significantly higher than in group 3 (P < 0.05). Femoral neck BMC in group 1 was significantly higher than in groups 2 and 3 (P < 0.001). In conclusion, lumbar BMD and BMC in the edentulous group were significantly lower, whereas femoral neck BMD and BMC were significantly higher in edentulous group compared with the others. Our findings indicated that improvement in lifestyle factors and nutritional strategies for the treatment and prevention of osteoporosis may have additional benefit in reducing tooth loss