Recent within-twin estimates of the return to schooling that use instrumental variables to correct for measurement error are considerably higher than existing estimates. This paper extends Griliches’ [Griliches (1979) Sibling models and data in economics: beginnings of a survey, Journal of Political Economy 87, S37–S64]. analysis of sibling or twin estimates of the return to schooling to show t...

This paper presents a new method of statistical differencing for the enhancement of contrast images. Our approach controls the sharpening effect using two constants in such a way that enhancement occurs in intensity edges areas and very little in uniform areas. It has been proven that our method is superior to similar existent and can be applied to pre-process satellite images.

In this paper I review three key topics in CFD that have kept researchers busy for half a century. First, the concept of upwind differencing, evident for 1-D linear advection. Second, its implementation for nonlinear systems in the form of highresolution schemes, now regarded as classical. Third, its genuinely multidimensional implementation in the form of residual-distribution schemes, the mos...

enables to reconstruct the whole sequence X1, ...,Xn (rather than the sample up to a permutation) makes of Pn a very flexible tool to represent complex and highly non-symmetric statistics. One can, for instance think of two-sample sequential rank statistics, V -statistics or fractional ARIMA processes as treated in Barbe and Broniatowski [1997] , [1998a] and [1998b]. In these references, sequen...

An approach to support the sustained evolution of traceability links is proposed and outlined. A fine-grained differencing approach on the link endpoints is used to maintain the links in a scalable manner. Here scalable refers to large software systems with thousands of links. Details of the link model and representation are given followed by the process used to evolve traceability links.

In practice, signal extraction is based on finite samples X1, ..., XT and, very often, current estimates of the interesting components (t = T ) import: a socalled ‘concurrent’ or ‘real-time’ estimate of the trend or of its turning-points has a strong prospective content, since the future evolution of the time series is likely to be conditioned by this component. Whereas forecasting tools genera...

Steganography is a way of hiding the information transmitting from sender to receiver and making the communication invisible. To enlarge the capacity of hidden secret information and to produce indistinguishable stego-image from original image with human eye, a new steganographic approach using improved pixel value differencing in a segment of four pixels and range table using perfect square nu...

Most of fire severity studies use field measures of composite burn index (CBI) to represent forest fire severity and fit the relationships between CBI and Landsat imagery derived differenced normalized burn ratio (dNBR) to predict and map fire severity at unsampled locations. However, less attention has been paid on the multi-strata forest fire severity, which represents fire activities and eco...

Real-world financial time series often contain both linear and nonlinear patterns. However, traditional time series analysis models, such as ARIMA, hold the assumption that a linear correlation exists among time series values while leaving nonlinear relation into error terms. Based on financial theories, we argue that investor sentiment is the main contributor to nonlinear pattern of stock time...

In many intervention analysis applications, time series data may be expensive or otherwise difficult to collect. In this case the power function is helpful, because it can be used to determine the probability that a proposed intervention analysis application will detect a meaningful change. Assuming that an underlying autoregressive integrated moving average (ARIMA) or fractional ARIMA model is...