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We introduce a maximum likelihood ratio test to test if a specific proportion is the greatest in a multinomial situation with a single measurement. The test is based on partitioning the parameter space and utilising logratio transformations.

In August 2015 a Swedish newspaper claimed that the Sweden Democrats were the largest political party in Sweden based on the results of single poll. We ask ourselves if this is a correct conclusion, considering the fact that the three largest parties in the poll were of roughly the same size. We analyse the parameter space and identify the subspace where the Sweden Democrats are the largest party. Using this we construct a maximum likelihood ratio test and derive its distribution under the null hypothesis. We finally apply our test to the data and obtaining a p-value between 0.09 and 0.14 are able to refute the claim in the newspaper. Based on the available data one cannot draw the conclusion that the Sweden Democrats are the largest party in Sweden.

A large number of polls on party preferences are published today. In order to get an estimate of the changes in political opinion, the polls may be combined into a poll of polls. We discuss a method for combining polls using the fact that they are compositions and respecting the properties of the compositional sample space (the simplex). The method is easily implemented and the estimate may be computed in linear time. We provide an example with Swedish data from year 2007 to 2010. The method also allows us to present the deviations between the estimated compositions and the observed. In the data set, we note e.g. differences between different polling institutes.

We consider the problem of describing the correlation between two compositions. Using a bicompositional Dirichlet distribution, we calculate a joint correlation coefficient, based on the concept of information gain, between two compositions. Numerical values of the joint correlation coefficient are calculated for compositions of two and three components. We also present an estimator of the joint correlation coefficient for a sample from a bicompositional Dirichlet distribution. Two confidence intervals are also presented and we examine their empirical confidence coefficient using Monte Carlo study. Finally we apply the estimator to a data set analysing the correlation between the 1967 and 1997, and the 1977 and 1997 compositions of the government gross domestic product for the 50 U.S. states and District of Columbia.

Funding was provided fully by USAID-sponsored Partnerships for Enhanced Engagement in Research (PEER) Program's Cycle 6 project, entitled "Ecosystem services in a changing climate; assessing critical services in Bangladesh rice production landscapes." PEER is implemented by U.S. National Academy of Sciences (NAS) via USAID and NAS Prime Agreement No. AID-OAA-A-11-00012. D.L. (US partner on the PEER grant) acknowledges support from the National Science Foundation Long-term Ecological Research Program (DEB 1832042) at the Kellogg Biological Station, Michigan State University South Asia Partnership and MSU AgBioResearch. ; Since independence and over the years, pesticides have become a dominant feature of Bangladesh agriculture. To protect farmers' health, environment and to improve sustainability of chemical pest control quantitative understanding of farmers' behavior in pesticide use is critical. However, study on the levels of knowledge and awareness of farmers and the practices of pesticide use are often limited. We conducted a broad analysis on the effects of knowledge and awareness of farmers as well as the influence of the different associated stakeholders such as pesticide retailers and the government, on farmers' behavior in pesticide use from a detailed survey of 917 agricultural households in different regions of Bangladesh. Within eight protective behaviors (PBs) or PPEs were largely influenced by the crops growers and regions. Never discarding empty pesticide containers in the field, never applying pesticides more than prescribed by DAE or the instruction manual, selecting new types of pesticides recommended by DAE and purchasing low toxicity pesticides were the most adopted practices. Most farmers from the South-East region were adopting the PB of wearing mask, gloves and long sleeved clothes when spraying and farmers from South trusted the recommendations of pesticides by village leaders and neighbors. Majority of vegetables growers were well informed that pesticides were very harmful to the quality of agricultural products, the environment, and human health but not rice or mixed crops growers. Generally, PBs were positively affected by the perception of the consequences of farmers' behavior and knowledge of pesticide use but negatively influenced by action of governments and trust of retailers. It is important to recognize the differences that exist among different crops growers and locations. Attempt needs to bridge the gap among crop growers, locations and different stakeholder such as government agencies and retailers to develop policy. ; Publisher PDF ; Peer reviewed