mathy poo Flashcards
Event
outcome of a procedure or experiment
probability
proportion of times an event occurs
simple event
an outcome that can not be broken down any further, is the most detailed outcome possible
sample space
all possible outcomes of a probability experiment
law of large numbers
with repetition of experiment, relative frequency probability of event approaches actual probability
complementary events
complement of even is the opposite of that event, so when that event does not occurs.
unusual event
a rare event. probability of evens is sig low (bottom 0.05) or sig high (top 0.05)
P(A)
probability of event a
P(A w line on top)
probability that event A does not occur
compound event
combining two or more simple events
disjoint or mutually exclusive
events that can not occur at same time
independent events
occurrence of one event does not affect the probability of another event
5% guidelines for cumbersome calculations
if sample size is not more than 5% of population, selections can be treated as independent even if it is actually dependent
at least one
means one or more. to find this probability, find probability of none of that event(the complement) and subtract it from 1
confusion of the inverse
incorrectly thinking that P(B|A)=P(A|B)
random variable
numerical outcome of procedure
probability distribution
summary of random variables with corresponding probability values
discrete random variable
values are countable or finite
continuous random variable
values can have infinite # of values within an interval , usually measured/
standard normal distribution
normally distributed data with bell shaped curve, mean of 0 and standard deviation of 1
density curve
represents continuous probability distribution that has area totalling 1 under the curve are, probability and proportion are interchangeable and are found in body of table A.2
Z scores are written along the horizontal axis and probabilities/areas are regions under score
table A.2
standard normal distribution(z) , cumulative area from the LEFT
z score
represents the number of standard deviations a data value is from mean
