A method and technical tools for correction of range-bias caused by variation of photo-multiplier (PM) output pulses in amplitude and shape are considered. The method is based on preliminary estimation of a relationship between certain integral parameter of PM pulses and corresponding range-bias. This integral parameter is measured for each PM pulse in parallel with measurement of basic time in...

Managers always consider the precise estimation of sediments in watersheds due to various conditions, such assoil and water resources management, construction, infrastructure and economical and social issues. In this condition,an optimized determination of sediment rating equation (typical method until now for sediment yield estimation) isessential to investigate sediment yield in rivers. In th...

In this paper I study the statistical properties of a bias corrected realized variance measure when high frequency asset prices are contaminated with market microstructure noise. The analysis is based on a pure jump process for asset prices and explicitly distinguishes among different sampling schemes. Two important findings emerge from the theoretical and empirical analysis. Firstly, business ...

A 3.5 3.5 4.6 mm thick TlBr detector with pixellated Au/Cr anodes made by Radiation Monitoring Devices Inc. was studied. The detector has a planar cathode and nine anode pixels surrounded by a guard ring. The pixel pitch is 1.0 mm. Digital pulse waveforms of preamplifier outputs were recorded using a multichannel GaGe PCI digitizer board. Several experiments were carried out at 20 1C, with the ...

The correction of multiplicative bias in magnetic resonance images is an important problem in medical image processing, especially as a preprocessing step for quantitative measurements and other numerical procedures. Most previous approaches have used a maximum likelihood method to increase the probability of the pixels in a single image by adaptively estimating a correction to the unknown imag...

For fMRI time-series analysis to be statistically valid, it is important to deal correctly with temporal autocorrelation in the noise. Most of the approaches in the literature adopt a two-stage approach in which the autocorrelation structure is estimated using the residuals of an initial model fit. This estimate is then used to "prewhiten" the data and the model before the model is refit to obt...

Output from numerical models at high spatial and temporal resolutions is critical for modeling applications in a variety of disciplines. Prior to its use modeling, output climate must be brought finer resolution calibrated with respect observations. The calibration model output, referred as bias-correction, poses many statistical challenges. Here, we develop bias-correction method which systema...

BACKGROUND Within-person variability in measured values of a risk factor can bias its association with disease. The extent of this regression dilution bias for plasma fibrinogen was investigated using repeat measurement data collected at varying time intervals on 27 247 adults in 15 prospective studies. METHODS Regression dilution ratios (RDRs) were estimated from a linear regression of repea...

In this paper we provide a new methodology to analyze the (Gaussian) profile quasi likelihood function for panel regression models with interactive fixed effects, also called factor models. The number of factors is assumed to be known. Employing the perturbation theory of linear operators, we derive a power series expansion of the likelihood function in the regression parameters. Using this exp...

This paper establishes asymptotic properties of quasi-maximum likelihood estimators for spatial dynamic panel data with both time and individual …xed e¤ects when both the number of individuals n and the number of time periods T can be large. Instead of using the direct approach where we estimate both individual e¤ects and time e¤ects directly, we propose a data transformation approach to elimin...