1. Marketing
Research
Lec: Doç. Dr. Mehmet Emin İnal

2. Steps in Sampling Process
 Define the Population
 Frame the Population
 Chosee a Sample Design
 Draw the sample
 Execute the research

3. What is POPULATION?
 All the values and people that is
accounted
 Size of population differs regarding the
research
ugurpek
 Must include interested subjects and
values

4. How do we define population?
 Decide the focus group of research
(human, firms, hotels etc.)
 Decide the geographic area of
research( Turkey, Alanya etc.)
 Decide time interval

5. Sample
Subgroup of population that can present
the whole population

6. Why do we use sample?
 Budget limitation
 Time limitation
 Impossible to reach all population
 Urgency to reach results

7. Sampling steps
 Sample frame selection
 Choose a sample design
 Decide the sample size regarding the
budget, time limit

8. Sample frame selection
 Samplwe frame is a list or set of
directions identifying all the sample
units in the population
 It can be list of names,telephone
numbers, area map etc.
 Sample frame must be accurate and
corrected in order to succeed

9. Sample Design
Random Sampling Non-Random Sampling
Cost High Low
Accuracy High Low
Time Much Less
Acceptability Universal acceptance Rational Acceptance
Generability Good Bad

10. Random Sampling
 Each unit have equal chance to be
choosen
 No personal impact from reasearcher
 Sampling error can be calculated
 No guaratee to present the population
perfectly ( bias may happen)

11. Random Sampling
1. Simple random sampling
2. Systematic sampling
3. Cluster sampling
4. Stratified sampling

12. 1.Simple Random Sampling
 Equal chance to be
chosen
 Sampling size must be
decided

13. 2. Systematic Sampling
 Easiest way of random sampling
 Use a pattern ,system to choose
sample
 No need to have full list of sample

14. 3. Cluster Sampling
 To cluster sample within the
geographical districts
 Easy to manage
 Less costly
 Generability is a problem

15. 4. Stratified Sampling
 To use subgroups of sample
 Ex: use of ages