Economic Control of Quality of Manufactured Product.

Features of Financial Returns Modelling Price Volatility Forecasting Standard Deviations The Accuracy of Autocorrelation Estimates Testing the Random Walk Hypothesis Forecasting Trends in Prices Evidence Against the Efficiency of Futures Markets Valuing Options Appendix: A Computer Program for Modelling Financial Time Series.

Modelling Financial Time Series

The Topography of Vision in Mammals of Contrasting Life Style: Comparative Optics and Retinal Organisation

Central serous chorioretinopathy (CSC) is a disease of the retina characterized by serous detachment of the neurosensory retina secondary to one or more focal lesions of the retinal pigment epithelium (RPE). CSC occurs most frequently in mid-life and more often in men than in women. Major symptoms are blurred vision, usually in one eye only and perceived typically by the patient as a dark spot in the centre of the visual field with associated micropsia and metamorphopsia. Normal vision often recurs spontaneously within a few months. The condition can be precipitated by psychosocial stress and hypercortisolism. Ophthalmoscopic signs of CSC range from mono- or paucifocal RPE lesions with prominent elevation of the neurosensory retina by clear fluid - typical of cases of recent onset - to shallow detachments overlying large patches of irregularly depigmented RPE. The spectrum of lesions includes RPE detachments. Granular or fibrinous material may accumulate in the subretinal cavity. Serous detachment often resolves spontaneously. From first contact, counselling about the potential relation to stress and glucocorticoid medication is warranted. After 3 months without resolution of acute CSC or in chronic CSC, treatment should be considered. Resolution of detachment can usually be achieved in acute CSC by focal photocoagulation of leaking RPE lesions or, in chronic CSC, by photodynamic therapy. The effect of therapy on long-term visual outcome is insufficiently documented. Reattachment within 4 months of onset is considered a relevant therapeutic target because prolonged detachment is associated with photoreceptor atrophy. This suggests that the value of treatment depends upon proper selection of cases that will not resolve without therapy. Chronic CSC may be difficult to differentiate from occult choroidal neovascularization secondary to CSC. Patients with chronic CSC who receive glucocorticoid treatment for systemic disease can often be managed without having to discontinue this medication.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1600-0420.2007.00889.x

Central serous chorioretinopathy

There are many applications of control charts in health-care monitoring and in public-health surveillance. We introduce these applications to industrial practitioners and discuss some of the ideas that arise that may be applicable in industrial monitoring. The advantages and disadvantages of the charting methods proposed in the health-care and public-health areas are considered. Some additional contributions in the industrial statistical process control literature relevant to this area are given. There are many application and research opportunities available in the use of control charts for health-related monitoring.

/pdf/the-use-of-control-charts-in-health-care-and-public-health-3gpbuh1ni4.pdf

The Use of Control Charts in Health-Care and Public-Health Surveillance

Summary

Different criteria of optimality are used in different subcultures of statistical surveillance One aim with this review is to bridge the gap between the different areas The shortcomings of some criteria of optimality are demonstrated by their implications Some commonly used methods are examined in detail, with respect to optimality The examination is made for a standard situation in order to focus on the inferential principles A uniform presentation of methods, by expressions of likelihood ratios, facilitates the comparisons between methods The correspondences between criteria of optimality and methods are examined The situations and parameter values for which some commonly used methods have optimality properties are thus determined A linear approximation of the full likelihood ratio method, which satisfies several criteria of optimality, is presented This linear approximation is used to examine when linear methods are approximately optimal Methods for complicated situations are reviewed with respect to optimality and robustness

Resume

Des differents criteres d'optimalite sont utilises dans differentes subcultures de la surveillance statistique Un des objectifs de cette etude est celui d'etablir un rapprochement entre les differentes disciplines Les faults de quelques uns des criteres d'optimalite sont montres par leurs implications Quelques methodes frequemment utilisees sont examinees en detail quant a leur optimalite Cet analyse est fait pour une situation standard, se concentrant sur les principes d'inference Une presentation uniforme des methodes, par expressions de rapports de vraisemblance, facilite la comparaison entre les methodes On examine les correspondances entre les criteres d'optimalite et les methodes On presente une approximation lineaire de la methode du rapport de vraisemblance totale, qui satisfait plusieurs criteres de optimalite Cette approximation lineaire est utilisee pour examiner quand les methodes lineaires sont approximativent optimales Des methodes pour des situations compliquees sont etudiees quant a leur optimalite est robustesse

/pdf/statistical-surveillance-optimality-and-methods-400b8v8yq2.pdf

Statistical surveillance. Optimality and methods.

Rheological analysis of soft collagenous tissue. Part I: theoretical considerations.

The needs for statistical surveillance in different areas of medicine are described. The predictive value of an alarm and other measures for the evaluation of alarm procedures are suggested. The measures are used to evaluate some common methods of continual surveillance of time series. It is demonstrated that some methods have about the same properties at the start of the surveillance period as later. This is however not the case for all methods. For some methods the consequence of an early alarm should be quite different from that of a late one.

Evaluations of methods for statistical surveillance.

Throughout the retina, the parameters of the probability distribution of visual acuity for monochromatic interference fringes are closely proportional to the number of retinal ganglion cells per degree of visual angle. There are no simple relationships to receptor spatial frequencies. These findings suggest that neuro-retinal acuity is determined principally by the spatial frequency of neural output channels.

A simple relationship between the probability distribution of visual acuity and the density of retinal output channels

When a control chart is used in practice, knowledge about several characteristics of the method is important for the judgement of which action is appropriate at an alarm. The probability of a false alarm, the delay of an alarm and the predictive value of an alarm are qualities (besides the usual ARL) which are described by a simulation study for the evaluations. Results for finite time are given for a shift in level of a Gaussian process. Evaluations are made of the full likelihood ratio method that has two parameters and can be made optimal for both the size and the intensity of a shift. Also, the Shiryaev-Roberts and the CUSUM methods are evaluated. These two methods have one parameter for the size of the shift. A comparison is also made with the commonly used Shewhart method. All methods are based on some likelihood ratio expressions. Differences and limiting equalities among the methods are demonstrated and also the robustness with respect to the choice of parameters.

/pdf/evaluations-of-likelihood-ratio-methods-for-surveillance-1unejbw3zr.pdf

Marianne Frisén

Papers

Statistical surveillance. Optimality and methods.

Rheological analysis of soft collagenous tissue. Part I: theoretical considerations.

Evaluations of methods for statistical surveillance.

A simple relationship between the probability distribution of visual acuity and the density of retinal output channels

Evaluations of likelihood ratio methods for surveillance. Differences and robustness