Chemical analysis: sources of error

Chemical and Physical Indicators in Drinking Water and Water Sources of Boroujerd Using Principal Components Analysis

Abstract Background and Objective: Quality control of drinking water is important for maintaining health and safety of consumers, and the first step is to study the water quality variables. This study aimed to evaluate the chemical and physical indicators, water quality variables and qualitative classification of drinking water stations and water sources in Boroujerd. Material and Methods...

Sources of error - Assignment

For all study participants, birth and death addresses were visited and a map of the wires and transformers of the electric power distribution was drawn. Homes were categorized as having "high-current configurations" (HCC), "low-current configurations" (LCC), or "very low current configurations" (VLCC), according to their proximity to high current distribution lines. Table 2 shows the distributi...

Data Analysis: potential pitfalls and sources of error

Multi-centre trials offer the ability to obtain larger amounts of MRI data per unit time than single-centre studies, and they are therefore very attractive for setting up large population studies. Typically, clinical studies aim at comparing some MRI-derived quantitative indices of pathology across groups of subjects, and/or at correlating them with other parameters, such as clinical scores. Th...

Sources of German unemployment: A structural vector error correction analysis

Instructors guide Sources of Error

from Bruneau et al. Needle exchange programs (NEPs) are designed to prevent human immunodeficiency virus (HIV) transmission among injection drug users. Although most studies report beneficial effects in terms of behavior modification, a direct assessment of the effectiveness of NEPs in preventing HIV infection has been lacking. A cohort study was conducted to assess the association between risk...