Lesson 6- Sampling Techniques & Pilot Studies Flashcards
What is the target population?
Target 🎯 population- group researchers studying- generalise results to
What is a sample?
Sample- representative of target 🎯 population- same characteristics
What is random sampling?
Random Sampling- every member- 🎯 population- same chance- being selected- e.g. names in 🎩
What are the evaluation points of random sampling?
Advantages:
1) 👍 for large 🎯 population- large sample represents & … results generalised
2) ✖️ researcher bias- sample chosen by chance & ✖️ by researcher- equal chance of selection
Disadvantages:
1) Difficult- get full details- 🎯 population & … select sample- e.g. all women in 🇬🇧
2) ✖️ all members of 🎯 population selected- willing to take part … ⬇️ sample size & sample unrepresentative
What is systematic sampling?
Systematic Sampling- pps selected- take every nth person from list
What are the evaluation points of systematic sampling?
Advantages:
1) ⬆️ simpler & needs ⬇️⏰ than random sampling- only list of 🎯 population needed
2) ✖️ researcher bias- sample chosen by chance & ✖️ by researcher- equal chance of selection
Disadvantages:
1) ✖️ all members of 🎯 population selected- willing to take part … ⬇️ sample size & sample unrepresentative
2) Selection may interact with hidden recurring/periodic trait … ✖️ representative of 🎯 population
What is stratified sampling?
Stratified Sampling- putting 🎯 population- categories- randomly sample each category- 👍 proportion
What are the evaluation points of stratified sampling?
Advantages:
1) All groups of 🎯 population included … sample representative to entire 🎯 population
Disadvantages:
1) ⏰ consuming- categories identified & calculated – details needed of 🎯 population
What is opportunity sampling?
Opportunity Sampling- selecting pps- readily available- willing to take part
What are the evaluation points of opportunity sampling?
Advantages:
1) Easy & practical compared to stratified sampling (⏰ & expensive 💵 )
Disadvantages:
1) ⬆️ chance sample ✖️ representative
2) Sometimes ppl obliged- take part- difficult to say no- unethical
What is volunteer sampling?
Volunteer Sampling- pps volunteer to take part- researchers advertise study
What are the evaluation points of volunteer sampling?
Advantages:
1) Saves ⏰ & effort- researcher advertises & waits for pps- ✖️ need to ask & ✖️ commitment issues
Disadvantages:
1) ⬆️ chance sample ✖️ represent 🎯 population (volunteer bias)
What are the 5 types of sampling?
1) Random
2) Systematic
3) Opportunity
4) Volunteer
5) Stratified
