Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
26 Cards in this Set
- Front
- Back
|
What are the measures of center?
|
Mean, Median, Mode
|
|
|
Mode
|
The mode is the value that occurs most frequently in a data set.
|
|
|
Mean
|
The mean is the sum of the observations divided by the number of observations.
|
|
|
Median
|
The median is the midpoint of the observations when they are ordered from smallest to largest.
|
|
|
Empirical Rule
|
68% of all of the observations in a data set are within 1 standard deviation of the mean, 95% are withing 2 standard deviations, and nearly all of the observations fall within 3 standard deviations. This is only the case if the distribution is bell shaped.
|
|
|
Outlier
|
An outlier is an observation that falls well above or well below the overall bulk of the data. Usually more than 3 standard deviations away from the mean.
|
|
|
Range
|
The range is the difference between the largest and smallest observations.
|
|
|
Deviation
|
The deviation is the difference between the observation and the sample mean (x-xhat)
|
|
|
Variance
|
The average of the squared deviations is called the variance.
|
|
|
What are the measures of position
|
Decile, Quartile, Percentile
|
|
|
Decile
|
Measure of position which is divided into 10 sections. Everything is by 10%'s
|
|
|
Quartile
|
Measure of position which is divided into quarters. 25% of the data is in each section.
|
|
|
Percentile
|
Measure of position in which the information is divided into 100 parts. Sometimes there is not enough data for this.
|
|
|
IQR
(inter quartile range) |
(Q3-Q1) it is used to get rid of outliers
|
|
|
Probability
|
The probability of a particular outcome is the proportion of times that the outcome would occur in a long run of observations.
How likely something is going to happen. |
|
|
Randomness
|
Randomness occurs when outcomes are unpredictable, not in a particular order, and nothing effects the outcome.
|
|
|
Long run behavior
|
If you do something long enough it will approach classical probability.
|
|
|
Law of large numbers
|
The more trials or the larger the sample, the closer your probability comes to "actual" probability.
|
|
|
What does it mean for two outcomes to be independent?
|
Outcome of one trial does not affect the outcome of another.
|
|
|
Disjoint/mutually exclusive
|
Two groups which have no outcomes in sommon.
|
|
|
What is sample space?
|
The set of all possible outcomes.
|
|
|
What is an event?
|
A subset of a sample space. Can be one outcome like rolling a one on a die, or a group of outcomes like rolling an even number on a die.
|
|
|
Addition Rule (if mutually exclusive)
|
P(A or B)= P(A) +P(B)
|
|
|
What is the multiplication rule?(for independent events only)
|
P(A and B) =P(A)xP(B)
|
|
|
Conditional Probability
|
The probability of an event given another even had occurred
P(A/B) = P(A and B)/ P(B) |
|
|
What is the multiplication rule for dependent events?
|
P (Aand B)= P(A) X P(B/A)
|
