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Frequency
(redirected from observed frequency)

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frequency: see harmonic motion harmonic motion, regular vibration in which the acceleration of the vibrating object is directly proportional to the displacement of the object from its equilibrium position but oppositely directed.
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; wave wave, in physics, the transfer of energy by the regular vibration, or oscillatory motion, either of some material medium or by the variation in magnitude of the field vectors of an electromagnetic field (see electromagnetic radiation).
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frequency

Number of waves that pass a fixed point per unit time; also, the number of cycles or vibrations undergone in unit time by a body in periodic motion. Frequency f is the reciprocal of the time T taken to complete one cycle (the period), or 1/T. The frequency with which earth rotates is once per 24 hours. Frequency is usually expressed in units called hertz (Hz). One hertz is equal to one cycle per second; one kilohertz (kHz) is 1,000 Hz, and one megahertz (MHz) is 1,000,000 Hz. The musical pitch A above middle C (the A string of a violin) has been widely standardized as 440 Hz.


frequency
The number of oscillations (vibrations) in one second. Frequency is measured in Hertz (Hz), which is the same as "oscillations per second" or "cycles per second." For example, the alternating current in a wall outlet in the U.S. and Canada is 60Hz. Electromagnetic radiation is measured in kiloHertz (kHz), megahertz (MHz) and gigahertz (GHz). See wavelength, frequency response, audio, carrier and space/time.

Frequency
The frequency is the number of oscillations per second. The higher the frequency (the closer the ripples would be in this diagram) and the shorter the wavelength.

frequency
1. Physics the number of times that a periodic function or vibration repeats itself in a specified time, often 1 second. It is usually measured in hertz.
2. Ecology
a. the number of individuals of a species within a given area
b. the percentage of quadrats that contains individuals of a species

frequency [′frē·kwən·sē]
(physics)
The number of cycles completed by a periodic quantity in a unit time.
(statistics)
The number of times an event or item falls into or is expected to fall into a certain class or category.

Frequency (wave motion)

The number of times which sound pressure, electrical intensity, or other quantities specifying a wave vary from their equilibrium value through a complete cycle in unit time. The most common unit of frequency is the hertz (Hz), which is equal to 1 cycle per second. In one cycle there is a positive variation from equilibrium, a return to equilibrium, then a negative variation, and return to equilibrium. This relationship is often described in terms of the sine wave, and the frequency referred to is that of an equivalent sine-wave variation in the parameter under discussion. See Frequency measurement, Sine wave, Wave motion


frequency
The number of oscillations per second (a) of the current or voltage in an alternating-current electric circuit, or (b) of a sound wave, or (c) of a vibrating solid object; expressed in hertz (abbr. Hz) or in cycles per second (abbr. cps).

Frequency 

The frequency of an event A is the ratio m/n of the number m of occurrences of A in a given series of trials to the total number n of trials. If the trials are independent and there is a definite probability p of the occurrence of A in an individual trial, then, for arbitrarily small ∊ > 0, at sufficiently large m it is practically certain that the frequency m/n satisfies the inequality

(seeLARGE NUMBERS, LAW OF and PROBABILITY).

The term “frequency” is used in mathematical statistics to designate the number of elements of a set that have a specified attribute.



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Therefore, both, the temporal as well as the spectral characteristics of the observed frequency band have to be known to the terminal.
To estimate the frequency of BB haplotypes that could be caused by DEBY reproduction (offspring from pure DEBY x DEBY and DEBY females x wild males crosses) we subtracted the natural background BB haplotype frequency from the observed frequency of BB haplotypes to obtain an estimate of the increase in the BB haplotypes that is potentially attributable to DEBY reproduction.
Significance tests are based on hyper-geometric probability estimates (see Bergman & El-Khouri, 1987); * = Observed frequency smaller than expected by chance alone (p < .
 
 
 
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