Generalized Newton-Raphson trajectory optimization-generator 1

Computer program constructs a sequence of optimal solutions to dynamically-approximate linear equations. Specification of the number and type of subarcs in the optimal solution allows simultaneous satisfaction of all switching criteria

Effects of radiation on charge-coupled devices

The effects of 1 MeV electron irradiation upon the performance of two phase, polysilicon aluminum gate CCDs are reported. Both n- and p-surface channel and n-buried channel devices are investigated using 64- and 128-stage line arrays. Characteristics measured as a function of radiation dose include: Transfer inefficiency, threshold voltage, field effect mobility, interface state density, full well signal level and dark current. Surface channel devices are found to degrade considerably at less than 10 to the 5th power rads (Si) due to the large increase in fast interface state density caused by radiation. Buried channel devices maintain efficient operation to the highest dose levels used

Absolute Calibration of a Large-diameter Light Source

A method of absolute calibration for large aperture optical systems is presented, using the example of the Pierre Auger Observatory fluorescence detectors. A 2.5 m diameter light source illuminated by an ultra--violet light emitting diode is calibrated with an overall uncertainty of 2.1 % at a wavelength of 365 nm.Comment: 15 pages, 8 figures. Submitted to JINS

Patient-reported outcome measures v. clinician-measured outcomes in community psychiatric practice

Aims and method We examine the feasibility of the routine use of three patient-reported and one clinician-rated outcome measures (patient-identified problem, EuroQol-5D questionnaire, EuroQol Visual Analogue Scale and Health of the Nation Outcome Scales (HoNOS)) in an out-patient community psychiatric service, and discuss the associations between these variables. Results The routine collection of outcome measures was feasible in the out-patient setting. There was a general improvement in the health status from the initial assessment to the first follow-up. Subsequent scores remained stable. Clinical implications The study encourages the practical use of scales in routine community psychiatric practice. As there was correlation between HoNOS and EQ-5D index, both need not be used in routine practice

Generation of folk song melodies using Bayes transforms

The paper introduces the `Bayes transform', a mathematical procedure for putting data into a hierarchical representation. Applicable to any type of data, the procedure yields interesting results when applied to sequences. In this case, the representation obtained implicitly models the repetition hierarchy of the source. There are then natural applications to music. Derivation of Bayes transforms can be the means of determining the repetition hierarchy of note sequences (melodies) in an empirical and domain-general way. The paper investigates application of this approach to Folk Song, examining the results that can be obtained by treating such transforms as generative models

Smooth Quantile Ratio Estimation

In a study of health care expenditures attributable to smoking, we seek to compare the distribution of medical costs for persons with lung cancer or chronic obstructive pulmonary disease (cases) to those without (controls) using a national survey which includes hundreds of cases and thousands of controls. The distribution of costs is highly skewed toward larger values, making estimates of the mean from the smaller sample dependent on a small fraction of the biggest values. One approach to deal with the smaller sample is to rely on a simple parametric model such as the log-normal, but this makes the undesirable assumption that the distribution of the log-expenditures is symmetric. We propose a novel approach to estimate the mean difference of two highly skewed distributions (Delta), which we call Smooth Quantile Ratio Estimation (SQUARE). SQUARE is obtained by smoothing, over percentiles, the ratio of the cost quantiles of the cases and controls. SQUARE defines a large class of estimators of Delta including: 1) the sample mean difference, 2) the maximum likelihood estimate under log-normal samples, and 3) L-estimates. We detail asymptotic properties of SQUARE such as consistency and asymptotic normality, and also provide a closed form expression for the asymptotic variance. Through a simulation study, we show that SQUARE has lower mean squared error than several competitors including the sample mean difference, and log-normal parametric estimates in several realistic situations. We apply SQUARE to the 1987 National Medicare Expenditure Survey to estimate the difference in medical expenditures between persons suffering from the smoking attributable diseases, lung cancer and chronic obstructive pulmonary disease, and persons without these diseases. Software in R (Ihaka and Gentleman, 1996) for the implementation of SQUARE and of all its special cases, and the cost data used in this paper are available at http://biostat.jhsph.edu/~fdominic/square.html

Parent-Child Sexual Communication Among Middle School Youth

Middle school youth (N=1472) in Central Indiana completed a survey about parent-adolescent sexual communi-cation. Being older, female, mixed race, ever had sex, ever arrested, and higher HIV knowledge were associatedwith more frequent sexual communication

The impact of CHIP premium increases on insurance outcomes among CHIP eligible children

Background: Within the United States, public insurance premiums are used both to discourage private health policy holders from dropping coverage and to reduce state budget costs. Prior research suggests that the odds of having private coverage and being uninsured increase with increases in public insurance premiums. The aim of this paper is to test effects of Children's Health Insurance Program (CHIP) premium increases on public insurance, private insurance, and uninsurance rates. Methods: The fact that families just below and above a state-specific income cut-off are likely very similar in terms of observable and unobservable characteristics except the premium contribution provides a natural experiment for estimating the effect of premium increases. Using 2003 Medical Expenditure Panel Survey (MEPS) merged with CHIP premiums, we compare health insurance outcomes for CHIP eligible children as of January 2003 in states with a two-tier premium structure using a cross-sectional regression discontinuity methodology. We use difference-in-differences analysis to compare longitudinal insurance outcomes by December 2003. Results: Higher CHIP premiums are associated with higher likelihood of private insurance. Disenrollment from CHIP in response to premium increases over time does not increase the uninsurance rate. Conclusions: When faced with higher CHIP premiums, private health insurance may be a preferable alternative for CHIP eligible families with higher incomes. Therefore, competition in the insurance exchanges being formed under the Affordable Care Act could enhance choice