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Linda J. Young, Michael Hyman and Barbara R. Rater

Abstract

The United States Department of Agriculture’s National Agricultural Statistics Service (NASS) has the responsibility of quantifying the nation’s agricultural production. Historically, it has focused on large production agriculture. With interest and activity increasing in urban areas, NASS has begun exploring how to better quantify urban agriculture. This segment of agriculture is particularly challenging to enumerate because the agricultural holdings tend to be small, diverse, widely dispersed, and more transient than the predominantly large farms in rural areas. In collaboration with the Multi-Agency Collaboration Environment (MACE), a new approach to list building was explored in a pilot study conducted in the City of Baltimore, Maryland. Using a big data approach, areas of potential agricultural activity were identified by gathering information (state and local permits, Facebook and twitter feeds, interest groups, etc.) via the web. A sample was drawn from the list, and an in-person survey was conducted to assess whether or not the identified areas had agricultural activity. The results of the pilot study are presented. Lessons learned from the study and next steps are discussed.

Open access

Alfred D. Tuttle, Jennifer L. Beck, Diane K. Willimack, Kevin P. Tolliver, Aryn Hernandez and Cha-Chi Fan

Abstract

The U.S. Census Bureau conducted a series of experiments to evaluate alternative contact strategies. We hoped to identify effective mail strategies that increase timeliness of response and reduce the number of cases receiving more-costly follow-ups. These experiments were incorporated into the collection of several annual business surveys and one quarterly survey. This article summarizes results from five experiments whose designs are based on business survey decision-making and response processes. We obtained clear, positive results from tests involving manipulation of mail sequences, but only modest results from tests in which we varied messages and envelope appearance, whose effects were seen only in specific industry subgroups.

Open access

Meri Boshkoska and Kosta Sotiroski

Abstract

Recent developments in the field of information and communication technologies (ICTs) have created new opportunities for enhancing both the operations and competitiveness within the banking sector. The application of contemporary ICT-based solutions has resulted in significant changes in the traditional banking business, through the involvement of brand new approaches in the process of distribution of banking products and services to customers. As a part of the services offered by any modern bank, e-banking has become a synonym for an efficient system aimed at delivering traditional banking services through electronic communications channels, available to anybody, anywhere and anytime. The goal of the paper is to perform an empirical analysis of the current situation regarding the level of customer usage and satisfaction with e-banking services in the Republic of Macedonia. The study will enable us to determine which variables affect the level of adoption and satisfaction with е-banking services. The study is fully based on the statistical data analysis of the responses gathered from a representative sample of e-banking customers.

Open access

Valiollah Rameeh

Summary

Half F2 diallel crosses of eight spring cultivars of rapeseed were used in partial circulant diallel analyses to estimate biometric genetic parameters for phenological traits, yield components and seed yield. The greatest variation in the GCA-to-SCA mean square ratio was related to days to flowering, and its lowest variation to days to maturity. A high coefficient of variation of the narrow-sense heritability estimate was obtained for days to maturity, followed by plant height and seed yield. For diallel analysis with a low number of parents, the differences of the heritability estimates of the traits were small; therefore, for precise estimation of heritability, a high number of diallel crosses will be preferred.

Open access

Peter van de Ven

Abstract

The compilation of official statistics has changed dramatically over the past decades, and it will continue to change. These changes not only relate to user demands; also the source data and the means, in the sense of the technologies available for compiling statistics, have undergone and will continue to undergo significant changes. This article addresses the main developments and challenges in relation to the sources for compiling official statistics (input), the technologies for processing data (throughput), and the user demands (output) for official statistics. It is concluded that all these changes have, and continue to have, a significant impact on the way statistics are compiled, and the article puts forward a number of suggestions for the future direction of compiling official statistics.

Open access

M. Iftakhar Alam and Mohaimen Mansur

Summary

This paper investigates a stopping rule to be utilised in phase I clinical trials. The motivation is to develop a dynamic rule so that a trial stops early if the maximum tolerated dose lies towards the beginning of a dose region. Also, it will employ many patients if the maximum tolerated dose lies towards the end of a dose region. A two-parameter logistic model is assumed for the dose-response data. A trial is stopped early before reaching the maximum number of patients when the width of the Bayesian posterior probability interval of the slope parameter meets a desired value. Instead of setting a pre-specified width to stop at, we determine it based on the parameter estimate obtained after a reasonable number of steps in a trial. Simulation studies of six plausible dose-response scenarios show that the proposed stopping rule is capable of limiting the number of patients to be recruited depending on the underlying scenario. Although the rule is applied to a D-optimum design here, it will be equally applicable to other model-based designs.

Open access

Jasper Edward Nyaura

Abstract

This paper examines the ethnicity as an issue prevailing upon the Kenyan society and its implication on the social, economic and political dimensions in Kenya. Devolved ethnicity has been seen to be on the arise since the county’s independence (1963) to date and therefore the distrust among communities is seen as an impediment to the socio-economic and political developments in Kenya. Moreover, the issues that arise include marginalization of minority ethnic communities towards accessing resources. Uneven distribution of national resources has led to underdevelopment of regions in Kenya thereby bring about regional imbalance in terms of distribution of national resources, which has negatively affected socio-economic development of the country. Negative ethnicity brings about marginalization, distrust and heightens ethnic tensions and this eventually leads to conflict, for example, the 1992, 1997 and the 2007/2008 post-election violence over the sharing and allocation of power and national resources. This paper examines ways in which ethnic problems in Kenya have been attributed to the social, economic and political perspectives and therefore provides the solution/medicine towards negative ethnicity.

Open access

Adela Delalić, Maja Čurković and Josipa Antić

Abstract

The paper provides an overview of the trend in the concentration of the total assets of banks in Croatia for the period from 2007 to 2016 with the aim of analysing and presenting the changes that occurred in the system. Also, the paper shows the theoretical framework of the indicators used in the research as well as the comparison of their obtained values. The data used to calculate the total assets concentration are taken from the Croatian National Bank. The concentration indices used in the study include the entropy measure, the Theil entropy, the Gini coefficient, the Pietra index, the Atkinson index and the coefficient of variation. The results indicate a very slight decrease in concentration over the past several years, while the coefficient of variation points to the heterogeneity of the system, as well as to inequalities among the banks, which are most evident in the size of banks assets.

Open access

Tamás Herendi

Abstract

The aim of the present paper is to provide the background to construct linear recurring sequences with uniform distribution modulo 2s. The theory is developed and an algorithm based on the achieved results is given. The constructed sequences may have arbitrary large period length depending only on the computational power of the used machines.

Open access

Thomas J. Faulkenberry

Summary

Bayesian inference affords scientists powerful tools for testing hypotheses. One of these tools is the Bayes factor, which indexes the extent to which support for one hypothesis over another is updated after seeing the data. Part of the hesitance to adopt this approach may stem from an unfamiliarity with the computational tools necessary for computing Bayes factors. Previous work has shown that closed-form approximations of Bayes factors are relatively easy to obtain for between-groups methods, such as an analysis of variance or t-test. In this paper, I extend this approximation to develop a formula for the Bayes factor that directly uses information that is typically reported for ANOVAs (e.g., the F ratio and degrees of freedom). After giving two examples of its use, I report the results of simulations which show that even with minimal input, this approximate Bayes factor produces similar results to existing software solutions.