Equations
Probability that an event occurs at least once
1-P(not occurring)
Outcomes that cannot happen at the same time are...
Mutually exclusive
Does the data set {1,2,3,4} represent a discrete or continuous variable
Discrete
Data that consist of numerical measurements is called...
Quantitative
Independence, Homogeneity, Goodness of Fit
What is the formula for expected value for Chi Square Test for Goodness-of-Fit
(row total)(column total)/(table total)
Events that do not affect the probability of a given outcome are...
Independent
Standard deviation is the square root of...
Variance
Data that consists of counts of various categories is called...
Categorical
Which two tests have the same formula for degrees of freedom
Homogeneity and Independence: (#rows-1)(#columns-1)
What is the formula for multiple outcomes occurring that are Not Mutually Exclusive
P(AUB) = P(A) + P(B) - P(AחB)
When the probability of each event will change with each trial, the events are...
Dependent
What do you call the average value of a variable over many trials
Expected Value
Chi square tests allow us to measure the extent to which the observed counts differ from the _____ counts
Expected
When running a Chi-Squared test, what three things must you report
Test Statistic, Degrees of Freedom, P-Value
What is the formula for the expected value of a discrete random variable
E(x) = Σ[(x)(px)]
What is conditional probability
The probability that an outcome will occur, given that a previous outcome has occurred
For continuous random variables, what is the probability of getting exactly one given outcome?
0
What two graphs are often used to represent categorical data
Bar graph, Mosaic Plot
How do you phrase the alternative hypothesis for a Goodness of Fit Chi-Squared Test
At least one of these proportions is not as specified in the null hypothesis
Formula to calculate the spread (st. dev.) of a discrete random variable by hand
√Σ[(xi-µx)2p(xi)]
What is the Law of Large Numbers?
Over a very large number of trials, the proportion of trials that result in the desired outcome will approach the value of the outcome's theoretical probability
If you subtract several distributions of a random variable, the spread...
Increases
What does the horizontal axis of a mosaic plot represent
The width of the bars shows the proportion of the population that is taken up by each sub-group
How do you phrase the null hypothesis differently for tests of Homogeneity vs. Independence
Homogeneity is the difference between distributions of a variable across populations, while independence is the association between variables within a population