Term
What is the most common summary measure of categorial data? |
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Definition
- proportion of successes
- propotion of outcomes for one category
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Term
What is the purpose of the Two-Way table? |
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Definition
To describe the relationship between 2 categorial variables |
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Term
Difference between Two-Way table and a Probability Distribution Table |
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Definition
- a two way table summaries a relationship between two categorial data
- a probability distribution table summaries one variable of the categorial data
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Term
Notation or Unit for the population proportion of successes, population proportion of failures, sample proportion for successes, and sample proportion of failures |
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Definition
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Term
What is random experiment |
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Definition
an act or process that leads to a single outcome that cannot be predicted with certainty |
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Term
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Definition
one outcome of a random experiment |
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Term
What is the sample space of a random experiment |
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Definition
the set of all simple event associated with a random experiment |
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Term
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Definition
a numerical value that indicated the chance that will occur when the random experiment is performed |
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Term
what are subjectibe probabilities |
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Definition
- reflection of the degree to which we believe the outcome will occur
- based on experience and intuitive judgement
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Term
what are priori classical probabilities |
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Definition
that are known or historical likelihood an event will occur withour having to run the random experiment |
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Term
what are empirical probabilities |
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Definition
- most common
- based on repeating experiments a very large number of times
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Term
3 ways to presenet a probability model |
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Definition
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Term
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Definition
a quantity having a numerical value for each member of a group |
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Term
What does it mean if 2 variable are disjoint? |
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Definition
no outcomes or simple events in common |
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Term
what does it mean when 2 variable create a joint event |
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Definition
- two events have outcomes in common
- intersection
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Term
what does it mean if 2 events are dependent events |
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Definition
the probability of their joint event:
- given to you in the stroy or the problem or provided as an intersection value in a probability table
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Term
What is largest and the smallest probability value? |
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Definition
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Term
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Definition
the sum of sample event probability |
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Term
are all joint events dependent events? |
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Definition
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Term
for a continuous random variable, how does one determine probabilities? |
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Definition
- x/n
- number of successes for the outcome of interest -------------------------------------------------------------
- total number of outcomes in the sample
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Term
why is P(X>2) = P(X>_2) true is X is a continuous variable but untrue if X is a discrete variable |
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Definition
because the continous variable just describes the variable rather than counting it |
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Term
for normally distributed variable, describe how one determines a probability answer |
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Definition
by standardizing all the x values to their corresponding Z scores |
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Term
why is the P(X=2)=0, if X is a normally distributed variable |
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Definition
because the probability corresponding to the area for 1 numerical value, among infinite values is too small to measure |
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Term
What are the properties of a normal distribution |
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Definition
- the mean=median
- perfectly symmetrical
- probability=area
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Term
what values can a normal random variable take on? or, what it the sample space for the random variable X, when X is normally distributed |
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Definition
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Term
What are 2 summary measures that describe or characterize a normal distribution |
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Definition
mean and standard deviation |
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Term
what is "standardizing" a random variable x |
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Definition
algebraically transforming all normal distributions into a standard normal distribution |
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Term
what does one need to standardize X |
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Definition
- mean
- standard deviation
- x
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Term
what does a z-score measure |
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Definition
the distance X if away from the mean in increments of the standard deviation |
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Term
what is the area determined by a cumulative probability of a value of x |
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Definition
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