Search results
Results from the WOW.Com Content Network
A sampling frame is often defined as a list of elements of the population we want to explore through a sample survey. A slightly more general concept considers that a sampling frame is a tool that allows the identification and access to the elements of the population, even if an explicit list does not exist. [1] Traditional sampling frames are ...
In statistics, a sampling frame is the source material or device from which a sample is drawn. [1] It is a list of all those within a population who can be sampled, and may include individuals, households or institutions. [1] Importance of the sampling frame is stressed by Jessen [2] and Salant and Dillman. [3]
A list of chemical analysis methods with acronyms. A. Atomic absorption spectroscopy (AAS) Atomic ... Analytical chemistry; List of materials analysis methods
[1] [2] A quadrat is suitable for sampling or observing plants, slow-moving animals, and some aquatic organisms. A photo-quadrat is a photographic record of the area framed by a quadrat. It may use a physical frame to indicate the area, or may rely on fixed camera distance and lens field of view to automatically cover the specified area of ...
In analytical chemistry, sample preparation (working-up) refers to the ways in which a sample is treated prior to its analyses. Preparation is a very important step in most analytical techniques, because the techniques are often not responsive to the analyte in its in-situ form, or the results are distorted by interfering species .
A laboratory specimen is sometimes a biological specimen of a medical patient's tissue, fluids, or other samples used for laboratory analysis to assist in differential diagnosis or staging of a disease process. These specimens are often the most reliable method of diagnosis, depending on the ailment.
In analytical chemistry, quantitative analysis is the determination of the absolute or relative abundance (often expressed as a concentration) of one, several or all particular substance(s) present in a sample. [1] It relates to the determination of percentage of constituents in any given sample. [2]
The concept can be extended when the population is a geographic area. [4] In this case, area sampling frames are relevant. Conceptually, simple random sampling is the simplest of the probability sampling techniques. It requires a complete sampling frame, which may not be available or feasible to construct for large populations. Even if a ...