On the Properties of Simulation-based Estimators in High Dimensions

Considering the increasing size of available data, the need for statistical methods that control the finite sample bias is growing. This is mainly due to the frequent settings where the number of variables is large and allowed to increase with the sample size bringing standard inferential procedures to incur significant loss in terms of performance. Moreover, the complexity of statistical models is also increasing thereby entailing important computational challenges in constructing new estimators or in implementing classical ones. A trade-off between numerical complexity and statistical properties is often accepted. However, numerically efficient estimators that are altogether unbiased, consistent and asymptotically normal in high dimensional problems would generally be ideal. In this paper, we set a general framework from which such estimators can easily be derived for wide classes of models. This framework is based on the concepts that underlie simulation-based estimation methods such as indirect inference. The approach allows various extensions compared to previous results as it is adapted to possibly inconsistent estimators and is applicable to discrete models and/or models with a large number of parameters. We consider an algorithm, namely the Iterative Bootstrap (IB), to efficiently compute simulation-based estimators by showing its convergence properties. Within this framework we also prove the properties of simulation-based estimators, more specifically the unbiasedness, consistency and asymptotic normality when the number of parameters is allowed to increase with the sample size. Therefore, an important implication of the proposed approach is that it allows to obtain unbiased estimators in finite samples. Finally, we study this approach when applied to three common models, namely logistic regression, negative binomial regression and lasso regression

A simple recipe for making accurate parametric inference in finite sample

Constructing tests or confidence regions that control over the error rates in the long-run is probably one of the most important problem in statistics. Yet, the theoretical justification for most methods in statistics is asymptotic. The bootstrap for example, despite its simplicity and its widespread usage, is an asymptotic method. There are in general no claim about the exactness of inferential procedures in finite sample. In this paper, we propose an alternative to the parametric bootstrap. We setup general conditions to demonstrate theoretically that accurate inference can be claimed in finite sample

Market Efficiency in the Kuala Lumpur Stock Exchange: Further Evidence Using Garch Model

The recent Asian currency crisis has revived the debate about the efficacy of the weak-form efficient market hypothesis as an appropriate tool for testing the volatility of the stock markets. This is because the idea that securities markets are efficient is a fundamental factor that affects not only the investment decisions but also all financial dealings in financial business. This study tested the weak-form version of efficient market hypothesis using the generalized autoregressive conditional heteroskedastic (GARCH) model on the monthly data of returns of stocks of listed under Kuala Lumpur Stock Exchange Market for the period 1994-99. In the pre-crisis results, GARCH effect was evident in 24 out of 30 companies (80%), suggesting that homoskedasticity (constant variance) hypothesis is rejected. In addition, the diagnostic test results indicated that the residuals were found to be uncorrelated for 26 out of 30 companies, while only 19 companies (63%) found to be to be normally distributed.The results of GARCH model during the crisis period were less evident, only 14 out of30 companies (slightly less than 50%) exhibit GARCH effect. Beside this, during the crisis period, only 20 out of 30 companies were not normally distributed, whereas 28 out of 30 companies have shown no autocorrelation, suggesting that weak form market hypothesis cannot be rejected. The results suggest that the characters of time series of the two periods have changed substantially during the crisis period but as the diagnostic test has shown, we cannot reject the weak form efficient market hypothesis for both periods

Conference review: The Association for the Treatment of Sexual Abusers (ATSA) 38th Annual Research & Treatment Conference, Wednesday 6 - Saturday 9 November 2019

For over thirty years, ATSA’s Annual Conference has brought together experts from across the globe to discuss best practices in sexual abuse prevention. The landmark four-day event offers various symposia, roundtables, clinics, and workshops relating to the treatment of individuals who have engaged in sexually offending behaviours, and is considered one of the most prolific regular mass-gatherings of sexual violence prevention advocates internationally. In this article, we review our experiences of ATSA’s 2019 Conference in Atlanta, Georgia and reflect on the key take-home lessons we learned from our first international conference

KADAR CHOLINESTERASE DALAM DARAH PETANI DI DUSUN TAENO, KECAMATAN TELUK AMBON, KOTA AMBON

A vegetable farmer group in Taeno Hamlet, Teluk Ambon District, Ambon City uses pesticides in farming. Based on interviews with farmer extension agents, the use of pesticides in Taeno Hamlet was not in accordance with regulations. Farmers also do not realize the importance of using PPE when applying pesticides and do not understand the correct attitude / method when spraying.  One indicator to monitor pesticide poisoning of farmers is blood cholinesterase testing. The purpose of this study was to determine the levels of Cholinesterase in the blood of farmers using pesticides in Taeno Hamlet, Teluk Ambon District, Ambon City. The research method used is descriptive experimental with laboratory testing. Cholinesterase examination will be carried out in Prodia's laboratory. The population in this study were 15 farmers in the "Taeno Mekar" group

KADAR CHOLINESTERASE DALAM DARAH PETANI DI DUSUN TAENO, KECAMATAN TELUK AMBON, KOTA AMBON

A vegetable farmer group in Taeno Hamlet, Teluk Ambon District, Ambon City uses pesticides in farming. Based on interviews with farmer extension agents, the use of pesticides in Taeno Hamlet was not in accordance with regulations. Farmers also do not realize the importance of using PPE when applying pesticides and do not understand the correct attitude / method when spraying.  One indicator to monitor pesticide poisoning of farmers is blood cholinesterase testing. The purpose of this study was to determine the levels of Cholinesterase in the blood of farmers using pesticides in Taeno Hamlet, Teluk Ambon District, Ambon City. The research method used is descriptive experimental with laboratory testing. Cholinesterase examination will be carried out in Prodia's laboratory. The population in this study were 15 farmers in the "Taeno Mekar" group

Expanding the CRISPR toolbox in Culicine mosquitoes: in vitro validation of Pol III promoters

CRISPR–Cas9-based “gene drive” technologies have been proposed as a novel and effective means of controlling human diseases vectored by mosquitoes. However, more complex designs than those demonstrated to date—and an expanded molecular toolbox with which to build them—will be required to overcome the issues of resistance formation/evolution and drive spatial/temporal limitation. Foreseeing this need, we assessed the sgRNA transcriptional activities of 33 phylogenetically diverse insect Polymerase III promoters using three disease-relevant Culicine mosquito cell lines (Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus). We show that U6 promoters work across species with a range of transcriptional activity levels and find 7SK promoters to be especially promising because of their broad phylogenetic activity. We further show that U6 promoters can be substantially truncated without affecting transcriptional levels. These results will be of great utility to researchers involved in developing the next generation of gene drives