Population
An entire group of objects - people, animals, plants, from which data can be collected 
Sample
A subset of the population
Representative Sample
A subset of the population that has the same characteristics as the population
Random Sample
One reliable way to produce a representative sample of a population
Convenience Sample
One unreliable way to produce a sample of a population, which is probably not representative
Inference
A conclusion made by interpreting data
Valid Inference
An inference that is very likely to be true about the population. If it is based on a representative sample, and there is enough data to support it, and inferences valid.
What are the measures of Center
Mean, Median, Mode
What are the measures of variability?
MAD, Range, IQR
Likelihood and probability
A ratio between 0 and 1
Theoretical probability
The likelihood that an event will happen, based on knowing all the possible outcomes. What we expect will happen
Experimental probability
Also called Relative Frequency; The ratio of the number of times an event actually occurs compared to the total number of trials
Population models
Include sample space, and probabilities of each possible outcome
Sample Space
The set of all possible outcomes
Outcomes of compound events
Probability of more than one event
How do you find the probability of a compound event?
To find the probability of a compound event, you need to make a table a tree diagram, or an organized list to create your sample space
Probabilities of compound events, simulations
A simulation is a model of a real world situation that can be used to find probabilities
How do you find the mode?
By looking at, whichever one is the most popular
How do you find the mean?
At all the numbers together and divide by the number of total numbers
How do you find the median?
Find whichever number is in the middle. If there are two numbers, add the two numbers and divide by two that is your new median.
How do you find the range?
Subtract the lowest value from the greatest value
How do you find the IQR?
Find the difference between the upper and lower quartile ranges or medians
How do you find the MAD?
First find the mean. Then subtract all your data points by the mean. Then add up your new data points and divide them by the total number of data points.
What does MAD stand for?
Mean absolute deviation
