Representative Sampling
Representative Sampling - Related Videos
02:13
The Representativeness Heuristic
0 Views •
2020
The representative heuristic describes a biased way of thinking, in which you unintentionally stereotype someone or something. For example, you may assume that your professors spend their free time reading books and engaging in intellectual conversation, because the idea of them spending their time playing volleyball or visiting an amusement park does not fit in with your stereotypes of professors. This text is adapted from OpenStax, Psychology. OpenStax CNX.
01:30
The Representativeness Heuristic
0 Views •
2026
The representativeness heuristic is a cognitive shortcut where individuals categorize events, objects, or people based on perceived similarities to familiar patterns rather than objective probability. While this mental shortcut facilitates rapid decision-making, it can also lead to systematic biases and flawed reasoning. In the context of behavioral finance, this heuristic significantly shapes investor decision-making, often leading to erroneous assessments of market trends and company...
01:29
Representativeness Heuristic
0 Views •
2025
The representativeness heuristic makes people judge likelihoods based on similarity to a stereotype rather than actual data. This can lead to base rate neglect, where people ignore important facts—like success rates or experience—in favor of a mental shortcut. As a result, decisions often become predictably biased rather than accurate.Take Claire, a manager at a tech company. She needs to choose a team lead for a new project. Alex is confident and well-spoken, fitting Claire’s idea of a leader.
07:55
An All-in-one Sample Holder for Macromolecular X-ray Crystallography with Minimal Background Scattering
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Cited by 4 •
2019
A novel sample holder for macromolecular X-ray crystallography along with a suitable handling protocol is presented. The system allows crystal growth, crystal soaking and in situ diffraction data collection at both, ambient and cryogenic temperature without the need of any crystal manipulation or mounting.
06:25
Capturing Representative Hand Use at Home Using Egocentric Video in Individuals with Upper Limb Impairment
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Cited by 17 •
2020
A protocol is proposed to capture natural hand function of individuals with hand impairments during their daily routines using an egocentric camera. The goal of the protocol is to ensure that the recordings are representative of an individual's typical hand use during activities of daily living at home.
FAQs
Spatial heterogeneity means composition varies from one location to another, while temporal heterogeneity means it changes over time. A sample taken from only one point or moment may therefore overstate or miss important constituents in the larger material. Recognizing both patterns helps analysts choose a selection plan that reduces bias and makes chemical measurements more interpretable.
Random selection helps avoid consciously favoring particular locations or portions. Systematic selection distributes collection across a planned sequence, while stratified selection separates the material into relevant groups before choosing portions from each. The appropriate approach depends on how the batch, environment, or process stream is organized and where composition may differ. These designs address heterogeneity in different ways.
Multiple increments capture variation that a single portion could miss. Combining them produces a sample that better represents the material as a whole, while homogenization helps distribute constituents throughout the portion submitted for measurement. This is especially important when composition is uneven, because an isolated fragment could otherwise create a misleading result and increase sampling error.
Sampling bias occurs when the selected portion does not reflect the population or batch, even if the subsequent laboratory measurement is performed correctly. Deliberate selection across relevant locations or times, followed by appropriate combination or homogenization, improves the connection between the tested portion and the source material. The resulting data provide a stronger basis for interpreting composition.
A practical plan identifies the material or batch, considers possible spatial and temporal variation, selects a random, systematic, or stratified approach, and collects multiple increments where appropriate. The increments may then be combined or homogenized before analysis. Analysts should also document how the sample was obtained, because sampling records support interpretation of the final chemical result.
The approach supports testing of raw materials, pharmaceutical products, environmental samples, and process streams. In each setting, uneven composition can make a narrowly selected portion uninformative or misleading. Representative collection improves the usefulness of quality-control data, helps analysts interpret chemical measurements in context, and supports decisions about materials or processes based on the broader sample population.
Documentation records how the portion was selected, how increments were collected, and whether combination or homogenization occurred. This information allows others to judge whether the result reflects the intended material and to interpret possible sources of sampling error. In chemistry, such traceability strengthens quality-control conclusions, regulatory decisions, and confidence in comparisons between batches or samples.