magnetotelluric (mt) method is an important passive surface geophysical method which uses the earth’s natural electromagnetic fields to investigate the electrical resistivity structure of the subsurface. the depth of investigation of mt is much higher than that of other electromagnetic (em) methods (vozoff, 1991). for a general conductivity distribution in the earth, the horizontal electric fie...

Most of economic and financial time series have a nonstationary behavior. There are different types of nonstationary processes, such as those with stochastic trend and those with deterministic trend. In practice, it can be quite difficult to distinguish between the two processes. In this paper, we compare random walk and determinist trend processes using sample autocorrelation, sample partial a...

Determining trend and implementing detrending operations are important steps in data analysis. Yet there is no precise definition of "trend" nor any logical algorithm for extracting it. As a result, various ad hoc extrinsic methods have been used to determine trend and to facilitate a detrending operation. In this article, a simple and logical definition of trend is given for any nonlinear and ...

PURPOSE To evaluate the effects of tafluprost treatment for 3 years on intraocular pressure (IOP) and visual field performance. METHODS The IOP of 55 patients with normal-tension glaucoma was monitored every 1-3 months for 3 years. The Humphrey visual field test was performed every 6 months after treatment and results compared with before-treatment results. Visual field performance was also e...

Predictions of uprising or falling trends are helpful in different scenarios in which users have to deal with huge amount of information in a timely manner,such as during financial analysis. This temporal aspect in various cases of data analysis requires novel data mining techniques. Assuming that a given set of data, e.g. web news, contains information about a potential trend, e.g. financial c...

One of the most important effective factors in the economic growth is the increased efficiency of manufacturing sectors. Thus, it is necessary to review and measure the efficiency of business units from a variety of dimensions to plan the increase of efficiency in future courses. One of these dimensions is the economics to scale (ES) referring to the concept of enhanced earnings due to the incr...

The trend-renewal-process (TRP) is defined to be a time-transformed renewal process, where the time transformation is given by a trend function λ(·) which is similar to the intensity of a nonhomogeneous Poisson process (NHPP). A nonparametric maximum likelihood estimator of the trend function of a TRP can be obtained much in the same manner as for the NHPP using kernel smoothing. But for a TRP ...