Standard error estimation for EM applications related to Latent class models

The EM algorithm is a popular method for computing maximum likelihood estimates. It tends to be numerically stable, reduces execution time compared to other estimation procedures and is easy to implement in latent class models. However, the EM algorithm fails to provide a consistent estimator of the standard errors of maximum likelihood estimates in incomplete data applications. Correct standard errors can be obtained by numerical differentiation. The technique requires computation of a complete-data gradient vector and Hessian matrix, but not those associated with the incomplete data likelihood. Obtaining first and second derivatives numerically is computationally very intensive and execution time may become very expensive when fitting Latent class models using a Newton-type algorithm. When the execution time is too high one is motivated to use the EM algorithm solution to initialize the Newton Raphson algorithm. We also investigate the effect on the execution time when a final Newton-Raphson step follows the EM algorithm after convergence. In this paper we compare the standard errors provided by the EM and Newton-Raphson algorithms for two models and analyze how this bias is affected by the number of parameters in the model fit.peer-reviewe

White Paper on Engineering Controls for Bioaerosols in Non-Industrial/ Non-Healthcare Settings

The list of disease pathogens that can be transmitted in the air is extensive. This list includes the common cold, SARS, measles, Hansen\u27s disease (leprosy), polio, influenza, Legionella (Legionnaires’ disease and Pontiac fever), and tuberculosis (TB). TB, SARSCoV-1, avian influenza, varicella, and now SARS-CoV-2 all have received public notice due not only to their known or assumed ability to be transmitted in the air rapidly from one individual to another, but also for their virulence. Other bioaerosols that can be transmitted through the air include bacteria, fungal spores and fragments, dust mites, and pollen. This document was developed to address control of bioaerosols transmission, primarily through ventilation and other engineering controls. This monograph will focus on engineering controls in non-industrial/non-healthcare facilities such as office buildings, schools, public assembly, theaters, and governmental buildings. It does not, however, address ventilation in residences, either single or multi-family

DESIGN, MANUFACTURE AND INSTALLATION OF APWSS (AUTOMATED PULSED WATERJET STRIPPING SYSTEM)

ABSTRACT Starting from an extensive laboratory study, a totally automated and integrated pulsed waterjet stripping system was installed at Vector Aerospace in Canada. The function of the APWSS (Automated Pulsed Waterjet Stripping System) is to strip thermal barrier coating (TBC) and a variety of other hard coatings from aircraft engines and other complicated parts. The system is currently undergoing thorough testing for reliability, reproducibility and other requirements for stripping. Organized and Sponsored by the WaterJet Technology Associatio

Opinion of Counsel on Treasury Statement; Statement of Principles on Practice in Income Tax Field

https://egrove.olemiss.edu/aicpa_comm/1189/thumbnail.jp

Congress restored, political and economic developments in contemporary India

"August 1981."Prepared for the fourth Joint Soviet-American Conference on Asia, Tashkent, September 1981"#2340"--handwritten on cove

Declaración de Boston

In a historic meeting at Boston College, more than 40 theologians from Latin America, Spain, and the U.S. discussed ways to unite both the practice and theology of the Catholic Church to complement Pope Francis’ vision of a "poor church for the poor." This Ibero-American Conference of Theology is the first-of-its-kind gathering of Hispanic theologians in the U.S. and scholars from Latin America and Spain, who addressed three key topics: globalization, social and economic exclusion, and the challenge of interculturality or the integration of different cultures living in the same place.Durante varios días, teólogas y teólogos católicos de Ibero-América nos reunimos en Boston, Estados Unidos de América, con espíritu ecuménico, interreligioso, intercultural, integrador y solidario. La vocación eclesial nos lleva a pensar, investigar, aprender, enseñar y comunicar la riqueza de la fe cristiana en la Iglesia y la sociedad. Compartimos la vida, la oración, la Eucaristía, la reflexión y el diálogo para hacer un discernimiento en común de los nuevos signos de los tiempos de nuestra época. Ahora queremos compartir algunos frutos de nuestro trabajo con la comunidad eclesial y el público en general

English in Malta : from colonialism to heritage, from social differences to opportunity

Maltese, a Semitic language, is the mother tongue of the vast majority of Maltese nationals and is used alongside a variety of English, known as Maltese-English. Although English in Malta is an inheritance of a colonial past, it is widely regarded to be of fundamental importance. Most regular users of English in Malta are normally of high socio-economic status, thereby creating a situation in which social difference can be manifest through language choice. While providing a description of the linguistic situation in Malta, I will focus on the structure of Maltese-English and place it within its sociolinguistic context. I will illustrate how this variety constitutes an example of ‘difference’ in a relatively small linguistic community and discuss the implications of this within Malta’s bilingual/diglottic context.peer-reviewe

Occupational Hepatic Disorders in Korea

Occupational hepatic disorders are classified into toxic hepatitis, viral hepatitis, and chemical-induced malignancy in Korea. Toxic hepatitis cases were reported in workers who were exposed to dimethylformamide, dimethylacetamide, or trichloroethylene. Pre-placement medical examination and regular follow-up are necessary to prevent the development of toxic hepatitis. Viral hepatitis was chiefly reported among health care workers such as doctors, nurses and clinical pathology technicians who could easily be exposed to blood. Preventive measures for these groups therefore include vaccination and serum monitoring programs. Hepatic angiosarcoma caused by vinyl chloride monomer (VCM) exposure is a very well known occupational disease and it has not been officially reported in Korea yet. Some cases of hepatocellular carcinoma were legally approved for compensation as an occupational disease largely by overwork and stress, but not supported by enough scientific evidence. Effort to find the evidence of its causal relationship is needed