# probability

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## probability

[prob″ah-bil´ĭ-te]the likelihood of occurrence of a specified event, which is often represented as a number between 0 (never) and 1 (always) that corresponds to the long-run frequency at which the event occurs in a sequence of random independent trials under identical conditions, as the number of trials approaches infinity.

## prob·a·bil·i·ty (P),

(prob'ă-bil'i-tē),**1.**A measure, ranging from 0 to 1, of the likelihood of truth of a hypothesis or statement.

**2.**The limit of the relative frequency of an event in a sequence of

*N*random trials as

*N*approaches infinity.

## probability

/prob·a·bil·i·ty/ the likelihood of occurrence of a specified event, often represented as a number between 0 (never) and 1 (always) corresponding to the long-run frequency at which an event occurs in a sequence of random independent trials as the number of trials approaches infinity.## probability

[prob′əbil′itē]

Etymology: L,

*probabilitas***1**a measure of the likelihood that something will occur.

**2**a mathematic ratio of the number of times something will occur to the total number of possible occurrences.

## probability

Statistics p value The likelihood that an event will occur by chance alone, and given a value between 0–impossible and 1–certain; the higher the p value, the more likely that 2 or more sets of overlapping variables occurred randomly–ie, the less the likelihood that the 2 events are associated; the lower the p value, the greater is the likelihood that the events are not random associations–counterintuitive, but think it out in a dark quiet room, you'll get it. See Conditional probability, Empirical probability, Gaussian probability, Personal probability, Prior probability, Theoretic probability Vox populi An expression of the likelihood that a specific event will occur.## prob·a·bil·i·ty

(prob'ă-bil'i-tē)**1.**A measure, ranging from 0-1, of the degree of belief in a hypothesis or statement.

**2.**The limit of the relative frequency of an event in a sequence of N random trials as N approaches infinity.

## probability

See P-VALUE.## probability

the likelihood that a given event will occur. Probability is expressed either as values between zero (complete certainty that an event will*not*occur) and 1.0 (complete certainty that an event will occur) or percentage values between 0 and 100. Probability is used widely in SIGNIFICANCE tests.

## prob·a·bil·i·ty

(prob'ă-bil'i-tē)A measure, ranging from 0-1, of the degree of belief in a hypothesis or statement.

## probability,

*n*

**1.**an increased likelihood that something will occur.

*n*

**2.**a mathematic ratio of the number of times something will occur to the total number of possible occurrences.

## probability

the basis of statistics. The relative frequency of occurrence of a specific event as the outcome of an experiment when the experiment is conducted randomly on very many occasions. The probability of the event occurring is the number of times it did occur divided by the number of times that it could have occurred. Defined as:$$\hbox{p}={\hbox{x}\over (\hbox{x+y})$$

**where**

p = probability, x = positive outcomes, y = negative outcomes.

**prior probability**

estimation of the probability that a particular phenomenon or character will appear before putting the patient to the test, e.g. testing the probable productivity of a patient by testing its forebears.

**subjective probability**

the measure of the assessor's belief in the probability of a proposition being correct.

## Patient discussion about probability

**Q. What is the likelihood of my depression returning?** I have a history of severe depression. My mom is very against medication and counseling, and reluctantly allowed me to go on the lowest dosage of zoloft. It helped, but now she wants me to go off of it and stop going to my doctor. My fear is that my depression will return. What are the chances of my depression returning, and how can I handle it if and when it does?

**A.**hi kelly17 i agree with eleanor55, i donot have bi-polar-but it seems to me that the problem isnt YOU/it your mother-Im going to be real here-if your mother knows that the meds help why is she stopping them--I think the stigma of the disease is her problem,like the other members said, and if she is doing this to you for that reason/BAD ON HER---at 17 i think you are under age--I dont want to start a family feud but i think this is child abuse--talk to soom one at school teacher/ect----stay strong things get better with time you have a lot of friends her USE THEM---mrfot56