sampling

• representative sample 


  •  A sample that that closely matched the target population as a whole in terms of key variables and characteristics
• target population


  • The group that the researchers draws the sample from and wants to be able to generalise the findings to
• sampling frame 


  identifying a smaller group within this population

  • The sampling frame should be representative of the target population so that generalisations can be made.
• random sampling


  • A sampling technique where everyone in the target population has an equal chance of being selected (refers to the practice of using chance methods to allocate participants to the conditions of an investigation)
• stratified sample 


  • A sampling technique where every nth person in a list of the target population is selected
• opportunity sample 


  • A sampling technique where participants are chosen because they are easily available
• volunteer sample 


  • A sampling technique where participants put themselves forward to take part in research, often by answering an advertisement
• pilot study 


  small scale study conducted to ensure the method will work according to plan. If it doesn’t then amendments can be made. 
• evaluation of pilot studies 


  • A pilot study can help researcher identify problems with design, methodology, analysis of your study + gain feedback so that these issues are dealt with before you carry out the real study.
  • Requires time and money
  • Participants used in the pilot can’t be used in the real study, reducing the number of individuals from your target population available to you