Statistics and probability

• Population - the totally of subjects ( people, animals, or objects ).
• Sample- the subset chosen from population.
• Sampling- the process of taking samples
• Random Sampling- choosing representatives from the population
• Probability Sampling- that involves from random selection
• Non-Probability Sampling- that do not involve in random selection
• Lottery Sampling- is used when the population has differential levels sections
• Systematic Sampling- The listing of all elements in the population
• Stratified Sampling- wherein the population are group based on their homogeneity

  • constructed by classifying the population
• Convinience Sampling- researcher's gather data from nearby source
• Snowball Sampling- also known as chain-refferal sampling
• Quota Sampling- are picked for convinience but certain quotas are given to interviewers
• Volunteer Sampling- wherein the measure is painful
• Purposive Sampling- units are selected because they are have characteristics that they need to sample. Also known as judgemental sampling