Download ane jalsa karo

1. By
Vijay Mehta

2. What exactly IS a “sample”?

3. What do qualitative researchers
worry about?
II want to show
want to show
II want to see II really want my
really want my
want to see II want to
want to how social
how social
the world research
research
the world describe the
describe the change occurs.
change occurs.
through the approach to be
approach to be
through the context in a lot
context in a lot I’m interested in
I’m interested in
eyes of my flexible and
flexible and
eyes of my of detail.
of detail. how things come
how things come
respondents. able to change.
able to change.
respondents. to be.
to be.

4. Social actors are not
Social actors are not
predictable like objects.
predictable like objects.
Randomized events are
Randomized events are
irrelevant to social life.
irrelevant to social life.
Probability sampling is
Probability sampling is
expensive and inefficient.
expensive and inefficient.
Non-probability sampling is the
Non-probability sampling is the
best approach.
best approach.

5. Types of samples

6. Simple Random Sample
 Get a list or “sampling frame”
a. This is the hard part! It must not systematically exclude
anyone.
 Generate random numbers
 Select one person per random numbers

7. Systematic Random Sample
 Select a random number, which will be known as
k
 Get a list of people, or observe a flow of people
(e.g., pedestrians on a corner)
 Select every kth person
 Careful that there is no systematic rhythm to the flow or
list of people.
 If every 4th person on the list is, say, “rich” or “senior” or
some other consistent pattern, avoid this method

8. Stratified Random
Sample
1. Separate your population into groups or
“strata”
2. Do either a simple random sample or
systematic random sample from there
a. Note you must know easily what the
“strata” are before attempting this
b. If your sampling frame is sorted by, say,
school district, then you’re able to use this
method

9. Multi-stage Cluster Sample
 Get a list of “clusters,” e.g., branches of a
company
 Randomly sample clusters from that list
 Have a list of, say, 10 branches
 Randomly sample people within those branches
 This method is complex and expensive

10. The Convenience Sample
Find some people that are easy to find

11. The Snowball Sample
 Find a few people that are relevant to your topic.
 Ask them to refer you to more of them.

12. The Quota Sample
 Determine what the population looks like in terms of
specific qualities.
 Create “quotas” based on those qualities.
 Select people for each quota.

13. The Theoretical Sample

14. Accidental sampling
 A type of nonprobability sampling which involves
the sample being drawn from that part of the
population which is close to hand
 The researcher using such a sample cannot
scientifically make generalizations about the total
population
 In social science research, snowball sampling is a
similar technique

15. Panel sampling
 The method of first selecting a group of
participants through a random sampling
 Period of data collection is called a "wave“
 Panel sampling can also be used to inform
researchers about within-person health changes
due to age

16. How many?
 Qualitative researchers seek “saturation”
 “How many” isn’t the issue. Do you understand the
phenomenon? Have you learned enough?
 Mere numbers are irrelevant. You want “verstehn” or deep
understanding
 Quantitative researchers seek statistical validity
 Can you safely generalize to the population? Have you
systematically excluded anyone? (See the “famous
sampling mistake”)

17. Improving Response Rates
 Personalize the invitation
 Offer money -- no strings attached

18. Thank
You all