Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), is a native pest of dry beans (Phaseolus vulgaris L.) and corn (Zea mays L.). As a result of larval feeding damage on corn ears, S. albicosta has a narrow treatment window; thus, early detection of the pest in the field is essential, and egg mass sampling has become a popular monitoring tool. Three action thresholds for field and sweet corn...

in order to study the effect of pre and postharvest polyamines spraying on increasing vase life of alstroemeria (alstroemeriaaurantica cv.sukari), an experimental was conducted on completely randomized factorial design with two types polyamines (putrescine, spermine) in four levels (zero, five, 10, 15 and 20 mg/l). results showed that, 20 mg/l of putrescine and spermine treatments increased vas...

a field experiment was conducted to study the spatial relationships between weed seed bank and population and their distribution models in sugar beet crop (beta vulgaris) in 2009 at motahari  agricultural research station of karaj. sampling from seed bank before sugar beet drilling and weed population in three stages during the growing season were done using square (50*50 cm) and rectangle (25*...

With cumulative innovation and imperfect information about the value of innovations, intellectual property rights can result in hold-up and therefore it may be better not to have them. Extending the basic cumulative innovation model to include 'sampling' by second-stage firms, we find that the lower the cost of sampling, or the larger the differential between high and low value second-stage inn...

Abstract In sample surveys, it is usual to make use of auxiliary information to increase the precision of estimators. A general class of estimators is suggested to estimate the population mean for the variable under study in two stage sampling scheme. Some special cases of this class of estimators are considered and are compared by using a data set. It turns out that the newly suggested estimat...

T U.S. pharmaceutical industry spent upwards of $18 billion on marketing drugs in 2005; detailing and drug sampling activities accounted for the bulk of this spending. To stay competitive, pharmaceutical managers need to maximize the return on these marketing investments by determining which physicians to target as well as when and how to target them. In this paper, we present a two-stage appro...

This article reviews previously described methods of fresh tissue sampling from radical prostatectomy specimens for research and describes a method used in Oxford which is simple, logical and cost effective. The method utilises a systematic zonal approach to tissue procurement in order to meet the increasing requirement for research samples with detailed morphological information such as zone o...

A variety of estimators of the variance of the general regression (GREG) estimator of a mean have been proposed in the sampling literature, mainly with the goal of estimating the design-based variance. Estimators can be easily constructed that, under certain conditions, are approximately unbiased for both the design-variance and the model-variance. Several dual-purpose estimators are studied he...