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Related to Branchial arches: Branchial cyst, branchial fistula

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Autoregressive Conditional Heteroskedasticity

A statistical measure of the average error between a best fit line and actual data that uses past data to predict future performance. General Autoaggressive Conditional Heteroskedasticity is the most common way of doing this. See also: Fractal Distribution.
References in periodicals archive ?
Suggestions of a thyroglossal duct or bronchogenic origin notwithstanding, the consensus is that the lesion is caused by a failure of the fusion of the paired second branchial arches in the midline during the third and fourth weeks of fetal development.
In the embryology of present-day mammals, the developmental process in the bones and muscles of the first and second branchial arches involves a re-enactment of the evolutionary process than begot the mammalian middle ear.
For many years during the first half of the 20th century, it was well accepted that the middle ear develops primarily from the first and second branchial arches and that the ossicles are derived from various contributions by Meckel's cartilage, Reichert's cartilage, and the otic capsule.
The characteristic craniofacial features of this syndrome are believed to be the result of unilateral fetal developmental abnormalities of the first and second branchial arches.
What differentiates these internal branchial cysts from other cysts of the first, second, third, and fourth branchial arches is the fact that they form only in the pharynx and they do not produce any neck swelling.