Statistics

Variables & data

Raw data

Variable

Continuous variable

Discrete variable

Categorical Data

Extraneous Variable

Measures of central tendency/spread

Central tendency

Mean

Median

Mode

Weighted mean

Z-score

Spread

Range

Standard deviation

Variance

Quartiles

Interquartile range

Percentiles

Box and whisker plot

Graphs

Frequency diagrams

Histogram

Frequency tables

Bar Graph

Frequency Polygon

Relative Frequency Distribution

Cumulative Frequency Distribution

Circle Graph (or Pie Chart)

Pictographs

Scatter plot

Sampling techniques

Index

Population

Sample

Simple Random Sample

Systematic Sample

Stratified Sample

Cluster Sample

Multi-stage sample

Voluntary-response sample

Convenience Sample

Bias

Sampling Bias

Non-Response Bias

Response bias

Measurement bias

Correlation

Linear Correlation

Strong Correlation

Weak Correlation

Positive Correlation

Negative Correlation

Correlation Coefficient

Types of relationship

Non-linear Regression

Cause-and-Effect Relationship

Reverse Cause-and-Effect Relationship

Accidental Relationship

Presumed Relationship

Experimental Group

Control Group

Common-cause Factor