FOCUS ON POPULATION & SAMPLEJustifying what you do during your doctoral research

Slides and video by: www.doctoralnet.com

Confused about the issue of population vs sample in your dissertation study?

1. What is it all about?

2. Why is it important?

3. Where do you start?

CONSIDER:Regarding how you slice out population: Who is affected by the issues/challenges or problems around which your

study revolves? How much area does your study cover? What is the demographic make up of that group in that area? Are there any particular considerations that make them special or unique

from the wider diversity that surround them? Will the effect of the outcome of your study on this group be direct or

indirect? Merely of interest or will it create policy? If policy, who will the policy affect directly and indirectly

In comparison to…. Who can you get your hands on/get IRB permission to ask questions of,

through which you will develop your results? To what extent does the smaller group you will ask questions of, mirror the

larger group who may be affected?

Your Sample

Population that are affected by the issuePopulation that would be interested

Your classroom will be studied and mirrors the population of the district/state in this manner…..

Your district/state are especially concerned because…..

The United States/much of the world studies the affect of testing on students

Your SampleVariabl

e A

Variable C

Variable B

1) It is your task to convince your readers that your sample is indicative of the population to whom you claim your study to be of interest.

2) To the extent that your study is focused on multiple variables, you need to convince your audience that your sample contains them to the same likelihood or % as the wider population from which they are derived.

Your Sample1. Relationships may not be

apparent as is seen here

2. All relationships/demographics need to be sorted out

3. In order to believe that the sample is correct for the population

Students Defined to be

At-Risk

Who are at risk of failure

Reporting Test Anxiety

AS YOU CAN SEE…

The sample here is NOT the same As the sample here….

Variable A

Variable C

Variable B

Students Defined to be

At-Risk

Who are at risk of failure

Reporting Test

Anxiety

Question:Can you draw out each relationship and describe them?

Are they convincing?

How large is the full population as compared to the sample you can easily question?

Is it convincing to believe that answers from your small group will represent the larger group as well?

TYPE OF SAMPLE & MAKING A CASE FOR SIGNIFICANCE

Convenience Random Easy to obtain Credibility of results depends

on your convincing your reader that your sample equated to a large degree with the population from which they were drawn.

The closer to that population the more likely that credibility can be established

Must meet the standard that everyone a) in a larger but accurately distributed sample b) had an equal likelihood to participate

Credibility depends on your random controls and means of obtaining your sample population

Statistical likelihood that a random sample will represent the whole

Draw a convincing discussion of population /sample and…

• You will have a much easier time to demonstrate your work is credible, and reliable.

• Your committee will have smaller number of challenges before you can move forward

• Your work will have a greater likelihood of being picked up later/have greater affect on your field

For More Information1. Doctoral Net Academy (DNA)

a self guided way through the maze of writing a dissertation with regular opportunities to ask question of live advisors

2. Finishing Faster Groups adding accountability and support to the DNA mix

3. Both virtual and luxury retreats taking you away and offering still greater one on one support