PR 1 Lesson 2

• Data Collection is very important in the aspect of research
• Researcher should choose the proper sampling method to answer what was asked in the research problem
• Sampling


  A process used in statistical analysis in which a predetermined number of observations taken in larger population
• Types of Sampling: Sampling Methods

  • Probability Sampling
  • Non-probability Sampling
• Probability Sampling


  • Sample from a larger population are chosen using a method based on the theory of probability
  • Gets rid of bias in the population and gives a fair chance to all members to be included in the sample
• Simple Random Sampling


  Method of collecting data where every single member of a population is chosen randomly, merely by chance and each individual has the exact same probability of being chosen to be a part of a sample
• Cluster Sampling


  Researchers divide the entire population into sections or clusters that represent a population, and clusters are identified and included in a sample on the basis of defining demographic parameters such as age, location, sex etc.
• Systematic Sampling


  Members of a sample are chosen at regular intervals of a population, requires selection of a starting point for the sample and sample size that can be repeated at regular intervals, least time-consuming
• Stratified Random Sampling


  Population can be divided into smaller groups, that don't overlap but represent the entire population together, sample drawn from each group separately
• Non-probability Sampling


  Reliant on a researcher's ability to select members at random, not a fixed or pre-defined selection process which makes it difficult for all elements of a population to have equal opportunities to be included in a sample
• Purposeful/Purposive Sampling


  Most common sampling strategy, participants are selected or sought based on pre-selected criteria based on the research question, sample size may be predetermined or based on theoretical saturation
• Quota Sampling


  Participant quotas are preset prior to sampling, researcher attempts to gather data from a certain number of participants that meet certain characteristics such as age, sex, class, marital status, HIV status, etc.
• Snowball Sampling


  Also known as chain referral sampling, participants refer the researcher to others who may be able to potentially contribute or participate in the study, helps researchers find and recruit participants that may otherwise be hard to reach