LESSON 1 - Random Variables

Random variables

are characteristics or measurements that take on values as determined by chance.

Random variables

It is a set of possible values from a random experiment.

Random Experiment 

processes where the conditions may be replicated but outcomes cannot be determined with certainty

Sample space

are the set of values that a random variable can assume.

Outcomes

are the possible value in the sample space

Discrete Random variables

they are variables that can take on distinct and separate values. (countable values)

Continuous Random variables

they are variables that can assume an infinite number of values in a given interval.

Statistics

This is the science of conducting studies to collect, organize, sumamrize, analyze, and draw conclusions from data.

Systematic

Statistics has a ___ process.

Population

This is the entirety of the group, including all the members that form a set of data.

Sample

This is a few members of the population. These were taken to represent the characteristics or traits of the population.

Descriptive Statistics

This is used to say something or describe a set of information collected. It can also be represented with graphs.

Inferential Statistics

This is used to say something about a larger group / population using information colelcted from a small part of that population

Qualitative Variable

This describes a certain type of information without using numbers.

Quantitative Variable

This measures or identifies an information using numerical scales.

Discrete Variable

These values can be coutned using integral values.

Continuous Variable

This can assume any numerical value over an interval or intervals.

Independent Variable

This can be controlled. This is assumed to have a direct effect on the dependent.

Dependent Variable

This variable is the one being tested or measured. Its value may change according to the independent variable.

Measurement

This is the process of assigning value to a variable.

Nominal

This has no particular order with observation.

Ordinal

This describes a ranking or an order.

Interval Level

This is the actual amoount. The order and the difference between the variables can be known. It’s limitation is that it has no “true zero”

Ratio Level

This has the same properties as interval level, but it has z true zero. The order and the difference can also be described.