The Role of Conditional Likelihoods in Latent Variable Modeling

In psychometrics, the canonical use of conditional likelihoods is for the Rasch model in measurement. Whilst not disputing the utility of conditional likelihoods in measurement, we examine a broader class of problems in psychometrics that can be addressed via conditional likelihoods. Specifically, we consider cluster-level endogeneity where the standard assumption that observed explanatory variables are independent from latent variables is violated. Here, “cluster” refers to the entity characterized by latent variables or random effects, such as individuals in measurement models or schools in multilevel models and “unit” refers to the elementary entity such as an item in measurement. Cluster-level endogeneity problems can arise in a number of settings, including unobserved confounding of causal effects, measurement error, retrospective sampling, informative cluster sizes, missing data, and heteroskedasticity. Severely inconsistent estimation can result if these challenges are ignored.

Profile of Open Cholecystectomy at Dr. Moewardi Hospital Surakarta January 2016 – December 2017 (Retrospective Study)

Background. Cholelithiasis is a disease found in the general population throughout the world, and is influenced by several factors such as gender, age, and Body Mass Index. Gallstone disease is a common indication for surgery. The surgical procedure can be done in 2 ways, with an open cholecystectomy or laparoscopic cholecystectomy.Methods. This study was conducted on patients who were treated at the Regional General Hospital dr. Moewardi Surakarta from January 2016 to December 2017 with retrospective sampling. The patient's age, gender, weight, height, and length of stay were taken based on the data listed in the patient's medical record.Results. A total of 96 patients, consisting of 61 (63.54%) women and 35 (36.46%) men who met the criteria for inclusion in this study. The age of the patients ranged from 31 to 86 years with a mean of 52.16 years. According to the age category, namely <40 years and 40 years, there were 14 (14.58%) and 82 (85.42%) people from all respondents, respectively. Only 26 (27.1%) obese patients were found in this study. The mean length of post-operative hospitalization was 6.69 ± 3.47 days.Conclusion. Gender and length of post-operative hospitalization in this study have characteristics that are in accordance with several previous studies.

Profile of Open Cholecystectomy at Dr. Moewardi Hospital Surakarta January 2016 – December 2017 (Retrospective Study)

Background. Cholelithiasis is a disease found in the general population throughout the world, and is influenced by several factors such as gender, age, and Body Mass Index. Gallstone disease is a common indication for surgery. The surgical procedure can be done in 2 ways, with an open cholecystectomy or laparoscopic cholecystectomy.Methods. This study was conducted on patients who were treated at the Regional General Hospital dr. Moewardi Surakarta from January 2016 to December 2017 with retrospective sampling. The patient's age, gender, weight, height, and length of stay were taken based on the data listed in the patient's medical record.Results. A total of 96 patients, consisting of 61 (63.54%) women and 35 (36.46%) men who met the criteria for inclusion in this study. The age of the patients ranged from 31 to 86 years with a mean of 52.16 years. According to the age category, namely <40 years and 40 years, there were 14 (14.58%) and 82 (85.42%) people from all respondents, respectively. Only 26 (27.1%) obese patients were found in this study. The mean length of post-operative hospitalization was 6.69 ± 3.47 days.Conclusion. Gender and length of post-operative hospitalization in this study have characteristics that are in accordance with several previous studies.

Fertility, Mobility, and Educational Reproduction: A New Method to Estimate Prospective Models Using Retrospective Data

Prospective models of intergenerational reproduction consider not only the social reproduction of attributes such as education, but also the demographic reproduction of individuals who carry these attributes. This study introduces a method that substantially reduces the data requirements of prospective models. The method allows estimating prospective models based on retrospective data commonly available in surveys. It addresses two key issues – retrospective sampling bias, and the problem of identifying representative cohorts. Additionally, we introduce a decomposition technique disentangling social and demographic pathways of reproduction. We illustrate the method using German data from NEPS and SOEP, focusing on educational reproduction of German men and women born between 1930 and 1945. The analysis offers new estimates of the expected number of higher and lower educated children born to men and women of different levels of education. Findings show that reproduction is constrained by educational gradients in women’s fertility, particularly in West Germany. We conclude that prospective designs advance our understanding of social inequality and its reproduction in families. The method that we introduce will facilitate future prospective research on social stratification.