Latent class analysis (LCA) and latent profile analysis (LPA) are techniques that aim to recover hidden groups from observed data. They are similar to clustering techniques but more flexible because they are based on an explicit model of the data, and allow you to account for the fact that the recovered groups are uncertain. LCA and LPA are useful when you want to reduce a large number of conti...

The purpose of the present study was to compare the results of Configural Frequency Analysis (CFA) and solutions derived from Latent Class Analysis (LCA) to evaluate concordances and disconcordances regarding their outcomes. Explorative LCA was applied to the Big Five dataset described in Lautsch & Thöle (this issue). The comparative analyses of the LCA solutions and the CFA results demonstrate...

Littoral cell angioma (LCA) is a rare benign splenic vascular neoplasm. We report a case of a 58-year-old man with a 5.5-cm lesion in the upper pole of the spleen. A laparoscopic partial splenectomy was performed. He was discharged on the second postoperative day. Pathology revealed LCA. Laparoscopic partial splenectomy can be performed safely in selected cases and is an appropriate option in p...

Biofuels have been proposed as an ecologically benign alternative to fossil fuels. There is, however, considerable uncertainty in the scientific literature about their ecological benefit. Here, we review studies that apply life-cycle analysis (LCA), a computational tool for assessing the efficiency and greenhouse gas (GHG) impact of energy systems, to biofuel feedstocks. Published values for en...

The applications of and recent issues on life cycle assessment (LCA) for agriculture are reviewed in order to provide an integrated perspective on environmental and food safety issues. First, the relationship between the good agricultural practice (GAP) approach and LCA of agricultural production systems is discussed. Second, applications of LCA to agricultural production systems are surveyed m...

An analysis of the use-stage for pavement life-cycle assessment (LCA) is presented within a framework of an LCA tool developed for Illinois Tollway. Methodological choices that can significantly affect LCA results were evaluated in this study. The share of the use-stage in a comprehensive pavement LCA framework was evaluated with all life-cycle stages including materials, construction, use, mai...

let $pounds$ be the category of locally compact abelian groups and $a,cin pounds$. in this paper, we define component extensions of $a$ by $c$ and show that the set of all component extensions of $a$ by $c$ forms a subgroup of $ext(c,a)$ whenever $a$ is a connected group. we establish conditions under which the component extensions split and determine lca groups which are component projective. ...

In large-scale educational surveys, a latent regression model is used to compensate for the shortage of cognitive information. Conventionally, the covariates in the latent regression model are principal components extracted from background data. This operational method has several important disadvantages, such as the handling of missing data and the high model complexity. The approach introduce...

BACKGROUND The purpose of this study was to validate the accuracy of an alternative cervical cancer test - visual inspection with acetic acid (VIA) - by addressing possible imperfections in the gold standard through latent class analysis (LCA). The data were originally collected at peri-urban health clinics in Zimbabwe. METHODS Conventional accuracy (sensitivity/specificity) estimates for VIA...

Let $pounds$ be the category of locally compact abelian groups and $A,Cin pounds$. In this paper, we define component extensions of $A$ by $C$ and show that the set of all component extensions of $A$ by $C$ forms a subgroup of $Ext(C,A)$ whenever $A$ is a connected group. We establish conditions under which the component extensions split and determine LCA groups which are component projective. ...