Measuring Propagule Pressure
The total probability of establishment (E) can be determined using this equation. It considers the fact that each propagule has an independent chance of establishment:
(E) is the total probability of establishment (p) is the probability of a one propagule establishing (N) is the # of propagules arriving at specific location at a certain time (l) is the location (t) is the time
- It is to be noted that the equation can also be written as the standard asymptotic curve (sometimes termed the independence model):
Alpha=shape coefficient which is equivalent to –ln(l – p).
Measures of propagule pressure are have been shown to have specific relationships with the probability of establishment.(Leung et al. 2004)
Read more about this topic: Propagule Pressure
Famous quotes containing the words measuring and/or pressure:
“As an example of just how useless these philosophers are for any practice in life there is Socrates himself, the one and only wise man, according to the Delphic Oracle. Whenever he tried to do anything in public he had to break off amid general laughter. While he was philosophizing about clouds and ideas, measuring a flea’s foot and marveling at a midge’s humming, he learned nothing about the affairs of ordinary life.”
—Desiderius Erasmus (c. 1466–1536)
“Destiny is an absolutely definite and inexorable ruler. Physical ability and moral determination count for nothing. It is impossible to perform the simplest act when the gods say “no.” I have no idea how they bring pressure to bear on such occasions; I only know that it is irresistible.”
—Aleister Crowley (1875–1947)