prior probability

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Related to Prior probabilities: Posterior probabilities, Uninformative prior

prior probability

n
(Statistics) statistics the probability assigned to a parameter or to an event in advance of any empirical evidence, often subjectively or on the assumption of the principle of indifference. Compare posterior probability
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References in periodicals archive ?
According to E2E path measurement results, we can get each link prior probabilities in the set of I.
Experts could present a chart mapping different prior probabilities to posterior probabilities.
Ideally, everything that a person believes about a topic is quantitatively incorporated into the prior probabilities. For example, any concerns about misconduct or biased methodology in previous studies must be incorporated quantitatively into the prior probability values.
These prior probabilities reflect prior knowledge of how likely it is that the static or dynamic subclass can be obtained before a sequence actually appears.
The prior probabilities, that is, P(I(y) | y [member of] [[OMEGA].sub.i] [intersection] [[OMEGA].sub.x]) and P(v(y) | y [member of] [[OMEGA].sub.1] [intersection] [[OMEGA].sub.x]), were defined in (1) and (4), respectively.
(4) Click one the "Search scheme" button in the upper-right corner of the right window of Figure 6, and three top ranked OPSs including scheme No., scheme prior probability ([P.sub.mss]([S.sub.pi])), service name, provider name, and provider address are recommended in an increasing order of prior probabilities, which are shown through the "Search results" tab.
Bayes's Theorem updates prior probabilities with test results by considering the sensitivity, Se (probability of a positive test result for a positive individual), and specificity, Sp (probability of a negative test result for a negative individual), of the diagnostic test to produce an updated (posterior) probability, called the positive predictive value, PPV, that efficiently incorporates both sources of information using the formula:
For very low prior probabilities of intrusion, below about 2 X [10.sup.-5] for the dual IDS with IDSs "C" and "E" and 1 X [10.sup.-11] for dual identical IDS "C"s, the dual IDS with a "zero false alarm" (0 FA) IDS is better than one or both of the other dual IDSs analyzed in this paper.
In these situations, they do not have to rely merely upon prior probabilities of loss or sample information.
The optimum criterion setting 1n[beta]*, given the payoff matrix and the prior probabilities, was - 1.90 for the control group and the groups with invalid cues.
Both Stockmarr (1999) and the NRC II Report recognize this interesting result; however, by treating the problem from a Bayesian perspective and invoking prior probabilities that are a function of the size of the database, they argue the example is irrelevant.
Although patients judged the disease probabilities to be higher, after a positive diagnostic test, each of their four judgments was essentially the same for all diseases, including those with high and low prior probabilities, and with accurate and inaccurate tests.