Related Experiment Video

Updated: Jan 19, 2026

Prevalence and Incidence
01:08

Prevalence and Incidence

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Prevalence of presbycusis in an otologically normal population

Antonio Rodríguez-Valiente1, Óscar Álvarez-Montero1, Carmen Górriz-Gil1

  • 1Puerta de Hierro University Hospital, Department of Otorhinolaryngology, Autonoma University, Manuel de Falla, 1, Majadahonda, 28222 Madrid, Spain.

Abstract

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Prevalence and Incidence01:08

Prevalence and Incidence

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Conservation of Small Populations

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What is Population Genetics?

A population is composed of members of the same species that simultaneously live and interact in the same area. When individuals in a population breed, they pass down their genes to their offspring. Many of these genes are polymorphic, meaning that they occur in multiple variants. Such variations of a gene are referred to as alleles. The collective set of all the alleles within a population is known as the gene pool.
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Population Growth00:57

Population Growth

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In the field of psychology, there are several ways to organize measurements of a trait, feature, or characteristic (i.e., variables). Qualitative data, such as ethnicity, can be tabulated into a frequency count to provide information about the proportion, as well as the variety of groups in a sample or population. On the other hand, researchers can perform a wider set of calculations on quantitative data. The mean, mode, and median, for instance, are central tendency measures to identify a...
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Normal stress is a type of stress that occurs when forces act perpendicular, or normal, to a material's cross-sectional area. This stress often arises in structures when subjected to axial loading, which is the application of force along the axis of an object. A practical example of this can be found in bridge truss members.
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