Statistics and Probability
Discrete and Continuous Random Variable
We used to give name tags to something or someone that we don't know or acquainted with. We say Ms. X, Mr. Y, Dr. M, or even plant W. We call these letters or symbols in Algebra as variables. If Algebra deals with variables and constants that are manipulated and solved, Statistics and Probability basically deals with events or experiments, and the outcomes of them. Events and outcomes are also represented by variables like X. These variable can represent any outcome of an event or experiment like throwing a die, rolling a color wheel, taking a card from a deck, or throwing pair of coins. Specifically, we call X in Statistics as random variable.
Point and Interval Estimations
An estimate is a value or a range of values that approximate a parameter. It is based on sample statistics computed from sample data. Estimation is the process of determining parameter values.
The Null and Alternative Hypothesis
Hypothesis testing is a process that uses sample statistics to test a claim about the value of a population parameter. For example, an automotive manufacturer advertises that its new hybrid car has a mean mileage of 50 miles per gallon. To test this claim, a sample would be taken. If the sample mean differs enough from the advertised mean, you can decide the advertisement is wrong.