Term
| Probability Distributions |
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Definition
| Describe what will probably happen(for each value of a variable determined by chance) instead of what actually did happen, and are often given in the format of a graph, table or formula |
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Term
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Definition
| A variable (typically represented by x) that has a single numerical value, determined by chance, for each outcome of a procedure (or experiment) |
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Term
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Definition
| Either a finite number of values or countable number of values where "countable" refers to the fact that there might be infinitely many values, but they result from a counting process. EX; number of people in a pool.. |
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Term
| Continuous Random Variable |
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Definition
| Infinitely many values, and those values can be associated with measurements on a scale without gaps or interruptions. EX; the speed of a car.. |
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Term
| Requirements for a Probability Distribution |
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Definition
∑P(x) = 1
where x assumes all possible values
and
0 ≤ P(x) ≤ 1
for every individual value of x |
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Term
(Formula)
Probability Distribution Mean |
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Definition
μ = ∑ [x P(x)]
can be done on calculator by entering data in lists, then using STAT CALC 1-Var Stats L1,L2 ENTER; x bar is the mean |
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Term
(Formula)
Probability Distribution Standard Deviation |
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Definition
σ = √∑ [ (x - μ)² • P(x)]
can be done on calculator by entering data in lists, then using STAT CALC 1-Var Stat L1,L2; σx is the standard deviation |
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Term
(Formula)
Probability Distribution Variance |
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Definition
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Term
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Definition
Most values should lie within 2 standard deviations of the mean. We can therefore identify the "unusual" values by determining if they lie outside these limits;
maximum usual value = μ + 2σ
minimum usual value = μ - 2σ |
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Term
| Using Probabilities to Determine When Results are Unusual |
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Definition
-Unusually high if P(x or more) ≤ .05
-Unusually low if P(x or fewer) ≤ .05 |
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Term
| Binomial Probability Distribution |
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Definition
A procedure that meets all of the following requirements;
1. Has a fixed number of trials
2. Trials mush be independent
3. Each trial must have all outcomes classified into 2 categories (success, failure)
4. Probability of success remains the same in all trials |
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Term
| Notations for Binomial Probability Distributions |
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Definition
p denotes probability of success
q denotes probability of failure; 1-p=q
n denotes fixed number of trials
x number of successes in n trials |
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Term
(Formula)
Binomial Probability Distribution Mean |
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Definition
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Term
(Formula)
Binomial Probability Distribution Standard Deviation |
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Definition
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Term
(Formula)
Binomial Probability Distribution Variance |
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Definition
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Term
(Calculator)
Given a Binomial Probability Distribution, what function do you use to find the probability of exactly x successes among a trial? |
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Definition
binompdf(n,p,x)
2nd VARS, arrow up, select binompdf( |
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