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CHAPTER 5
CONDUCTING A
SURVEY
POPULATION AND SAMPLE
When the questionnaire is in its final form, the
researcher needs to determine what the
population of her study is and the what type
of sample she will take.
2
The population is the entire group of subjects
the researcher wants information on.
A sample is a subset of the population the
researcher actually examines to gather data.
3
GRAPHIC DISPLAY OF POPULATION AND
SAMPLE
4
Population
Sample
REPRESENTATIVE, RANDOM, AND
BIASED SAMPLES
5
Representative Sample is a sample in which the
people in the sample have the same
characteristics as the people in the population.
Random Sample helps to offset the confounding
effects of known and unknown factors by
randomly choosing cases
REPRESENTATIVE, RANDOM, AND
BIASED SAMPLES
6
Biased Sample is neither representative nor
random.
Rather than being snapshot of the population,
a biased sample is a sample, whose answers
do not reflect the answers we would get had
we the possibility to poll the whole population.
REPRESENTATIVE, RANDOM, AND
BIASED SAMPLES
There are different forms of biases survey responses can suffer from:
7
1. Selection Bias if the sample is not
representative of the population it should
represent.
REPRESENTATIVE, RANDOM, AND
BIASED SAMPLES
There are different forms of biases survey responses can suffer from:
8
2. Non-response Bias occurs if certain
individuals in your sample have a higher
likelihood to respond than others and if the
responses of those who do not respond would
differ considerably from the responses of
those who respond
REPRESENTATIVE, RANDOM, AND
BIASED SAMPLES
There are different forms of biases survey responses can suffer from:
9
3. Response Bias happens when
respondents answer a question misleadingly
or untruthfully.
SAMPLING ERROR
10
The examples described under biased
survey have high sampling errors, but
even with the most sophisticated
randomization techniques, we can never
have a 100% accurate representation of a
population from a sample.
NON-RANDOM SAMPLING TECHNIQUES
The most common non-probabilistic sampling techniques are:
11
1. Convenience Sampling is a type of non
probabilistic sampling technique where
people are selected because they are
readily available.
NON-RANDOM SAMPLING TECHNIQUES
The most common non-probabilistic sampling techniques are:
12
2. Purposive Sampling – subjects are
selected because of some characteristics
which the researcher predetermines
before the study.
NON-RANDOM SAMPLING TECHNIQUES
The most common non-probabilistic sampling techniques are:
13
3. Volunteer Sampling is a sampling
technique frequently used in psychology
or marketing research.
NON-RANDOM SAMPLING TECHNIQUES
The most common non-probabilistic sampling techniques are:
14
4. Snowball Sampling is typically
employed with populations, which are
difficult to access.
The researcher has to identify one or
several individuals of the group she wants
to study. He then asks the first
respondents if they know others of the
NON-RANDOM SAMPLING TECHNIQUES
The most common non-probabilistic sampling techniques are:
15
5. Quota Sampling is a technique where
sampling is done according to certain
preestablished criteria.
DIFFERENT TYPES OF SURVEYS
16
a) Face-to-Face Surveys is historically
the most commonly employed survey
method.
- The interviewer travels to the
respondent’s location, or the two meet
somewhere else.
DIFFERENT TYPES OF SURVEYS
17
b) Telephone Survey resembles the face-
to-face interview. Rather then personal,
the interaction between interviewer and
interviewee is via phone.
DIFFERENT TYPES OF SURVEYS
18
c) Mail-in Surveys are surveys that are
sent to peoples’ mailboxes. There is a
complete absence of an interviewer.
DIFFERENT TYPES OF SURVEYS
19
d) Online Surveys are essentially a special
form of mail in surveys. Instead of sending a
questionnaire by mail, researchers send
online survey by email or use a website such
as SurveyMonkey to host their questionnaire.
WHICH TYPES OF SURVEY SHOULD
RESEARCHERS USE?
20
While non of the aforementioned survey
types is a priori superior to the others, the
type of survey researchers should use
depends on several considerations.
WHICH TYPES OF SURVEY SHOULD
RESEARCHERS USE?
21
•It depends on the purpose of the research
and the researcher’s priorities.
•Surveys of a small subset of the population
who are difficult to reach by phone or mail,
such as the homeless, similarly require
face-to-face interaction.
WHICH TYPES OF SURVEY SHOULD
RESEARCHERS USE?
22
•For other surveys more relevant for
marketing firms and companies, an
online convenience sample might suffice
to draw some ‘valid’ inferences about
customer satisfactions with a service or
a product.
WHAT IS A PRE-TEST?
23
Questionnaire design is a complex; hardly
any expert can design a perfect
questionnaire by just sitting at her desk
(Campanelli 2008: 176)
WHAT IS A PRE-TEST?
24
A researcher should test her questions in
an authentic setting to see if the survey
as a whole and individual questions make
sense and are easily understood by the
respondents.
WHAT IS A PRE-TEST?
Such Preliminary research or pre-tests make particular sense in five cases
25
•First, for some questions researchers
need to decide upon several possible
measurements.
•Second, questions need to be culturally
and situationally appropriate, easy to
understand, and they must carry the
inherent concept’s meaning.
WHAT IS A PRE-TEST?
Such Preliminary research or pre-tests make particular sense in five cases
26
•Third, a pre-test can help researcher
discover if responses to a specific item
vary or not.
•Fourth, a pre-test is a particularly helpful
if the survey contains open-ended
questions and if a coding scheme for
these open-ended questions is
WHAT IS A PRE-TEST?
Such Preliminary research or pre-tests make particular sense in five cases
27
•Fifth, and more practically, a pre-test is
especially recommendable if a group of
interviewers (with little experience) run
the interviews.
HOW TO CONDUCT A PRE-TEST?
28
The creation of a questionnaire/survey is
a reiterative process.
•The researcher should check the questions
several times to see if there are any
uncertain or vague questions, if the question
flow is good, and if the layout is clear and
appealing.
HOW TO CONDUCT A PRE-TEST?
29
•She might run the survey with a friend or
colleague. This preliminary testing might
already allow the researcher to identify some
ambiguous or sensitive questions or other
problematic aspects in the questionnaire.
HOW TO CONDUCT A PRE-TEST?
30
•After the preliminary check, the researcher
should conduct a trial or pre-test to verify if
the topic of the questionnaire and every
single question are well understood by the
survey respondents.
OTHER REFERENCES:
Other Reference
•https://tinyurl.com/2p8ys283

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Chapter 5-EL 301.pptx

  • 2. POPULATION AND SAMPLE When the questionnaire is in its final form, the researcher needs to determine what the population of her study is and the what type of sample she will take. 2
  • 3. The population is the entire group of subjects the researcher wants information on. A sample is a subset of the population the researcher actually examines to gather data. 3
  • 4. GRAPHIC DISPLAY OF POPULATION AND SAMPLE 4 Population Sample
  • 5. REPRESENTATIVE, RANDOM, AND BIASED SAMPLES 5 Representative Sample is a sample in which the people in the sample have the same characteristics as the people in the population. Random Sample helps to offset the confounding effects of known and unknown factors by randomly choosing cases
  • 6. REPRESENTATIVE, RANDOM, AND BIASED SAMPLES 6 Biased Sample is neither representative nor random. Rather than being snapshot of the population, a biased sample is a sample, whose answers do not reflect the answers we would get had we the possibility to poll the whole population.
  • 7. REPRESENTATIVE, RANDOM, AND BIASED SAMPLES There are different forms of biases survey responses can suffer from: 7 1. Selection Bias if the sample is not representative of the population it should represent.
  • 8. REPRESENTATIVE, RANDOM, AND BIASED SAMPLES There are different forms of biases survey responses can suffer from: 8 2. Non-response Bias occurs if certain individuals in your sample have a higher likelihood to respond than others and if the responses of those who do not respond would differ considerably from the responses of those who respond
  • 9. REPRESENTATIVE, RANDOM, AND BIASED SAMPLES There are different forms of biases survey responses can suffer from: 9 3. Response Bias happens when respondents answer a question misleadingly or untruthfully.
  • 10. SAMPLING ERROR 10 The examples described under biased survey have high sampling errors, but even with the most sophisticated randomization techniques, we can never have a 100% accurate representation of a population from a sample.
  • 11. NON-RANDOM SAMPLING TECHNIQUES The most common non-probabilistic sampling techniques are: 11 1. Convenience Sampling is a type of non probabilistic sampling technique where people are selected because they are readily available.
  • 12. NON-RANDOM SAMPLING TECHNIQUES The most common non-probabilistic sampling techniques are: 12 2. Purposive Sampling – subjects are selected because of some characteristics which the researcher predetermines before the study.
  • 13. NON-RANDOM SAMPLING TECHNIQUES The most common non-probabilistic sampling techniques are: 13 3. Volunteer Sampling is a sampling technique frequently used in psychology or marketing research.
  • 14. NON-RANDOM SAMPLING TECHNIQUES The most common non-probabilistic sampling techniques are: 14 4. Snowball Sampling is typically employed with populations, which are difficult to access. The researcher has to identify one or several individuals of the group she wants to study. He then asks the first respondents if they know others of the
  • 15. NON-RANDOM SAMPLING TECHNIQUES The most common non-probabilistic sampling techniques are: 15 5. Quota Sampling is a technique where sampling is done according to certain preestablished criteria.
  • 16. DIFFERENT TYPES OF SURVEYS 16 a) Face-to-Face Surveys is historically the most commonly employed survey method. - The interviewer travels to the respondent’s location, or the two meet somewhere else.
  • 17. DIFFERENT TYPES OF SURVEYS 17 b) Telephone Survey resembles the face- to-face interview. Rather then personal, the interaction between interviewer and interviewee is via phone.
  • 18. DIFFERENT TYPES OF SURVEYS 18 c) Mail-in Surveys are surveys that are sent to peoples’ mailboxes. There is a complete absence of an interviewer.
  • 19. DIFFERENT TYPES OF SURVEYS 19 d) Online Surveys are essentially a special form of mail in surveys. Instead of sending a questionnaire by mail, researchers send online survey by email or use a website such as SurveyMonkey to host their questionnaire.
  • 20. WHICH TYPES OF SURVEY SHOULD RESEARCHERS USE? 20 While non of the aforementioned survey types is a priori superior to the others, the type of survey researchers should use depends on several considerations.
  • 21. WHICH TYPES OF SURVEY SHOULD RESEARCHERS USE? 21 •It depends on the purpose of the research and the researcher’s priorities. •Surveys of a small subset of the population who are difficult to reach by phone or mail, such as the homeless, similarly require face-to-face interaction.
  • 22. WHICH TYPES OF SURVEY SHOULD RESEARCHERS USE? 22 •For other surveys more relevant for marketing firms and companies, an online convenience sample might suffice to draw some ‘valid’ inferences about customer satisfactions with a service or a product.
  • 23. WHAT IS A PRE-TEST? 23 Questionnaire design is a complex; hardly any expert can design a perfect questionnaire by just sitting at her desk (Campanelli 2008: 176)
  • 24. WHAT IS A PRE-TEST? 24 A researcher should test her questions in an authentic setting to see if the survey as a whole and individual questions make sense and are easily understood by the respondents.
  • 25. WHAT IS A PRE-TEST? Such Preliminary research or pre-tests make particular sense in five cases 25 •First, for some questions researchers need to decide upon several possible measurements. •Second, questions need to be culturally and situationally appropriate, easy to understand, and they must carry the inherent concept’s meaning.
  • 26. WHAT IS A PRE-TEST? Such Preliminary research or pre-tests make particular sense in five cases 26 •Third, a pre-test can help researcher discover if responses to a specific item vary or not. •Fourth, a pre-test is a particularly helpful if the survey contains open-ended questions and if a coding scheme for these open-ended questions is
  • 27. WHAT IS A PRE-TEST? Such Preliminary research or pre-tests make particular sense in five cases 27 •Fifth, and more practically, a pre-test is especially recommendable if a group of interviewers (with little experience) run the interviews.
  • 28. HOW TO CONDUCT A PRE-TEST? 28 The creation of a questionnaire/survey is a reiterative process. •The researcher should check the questions several times to see if there are any uncertain or vague questions, if the question flow is good, and if the layout is clear and appealing.
  • 29. HOW TO CONDUCT A PRE-TEST? 29 •She might run the survey with a friend or colleague. This preliminary testing might already allow the researcher to identify some ambiguous or sensitive questions or other problematic aspects in the questionnaire.
  • 30. HOW TO CONDUCT A PRE-TEST? 30 •After the preliminary check, the researcher should conduct a trial or pre-test to verify if the topic of the questionnaire and every single question are well understood by the survey respondents.

Editor's Notes

  1. Normally the researcher or polling firm is not able to interview all units of the population
  2. In many social settings, it is basically impossible for researchers to match the population characteristics in the sample Large scale surveys use randomization techniques to select participants
  3. A sample is biased if some type of individuals such as middle-class men are overrepresented and other types such as unemployed women are under represented
  4. The source of this type of bias is .self-selection bias. Respondents normally have their entirely free will to decide whether or not to participate in the survey. Naturally, some people are more likely to participate than others are.
  5. The most common form of response bias is the so-called social desirability bias; respondents might try to answer the questions less according to their own convictions but more in an attempt to adhere to social norms
  6. Purposive sampling can be very useful in situations where the researcher needs information for a specific target or group. A common from of purposive sampling is expert sampling. Example a researcher sends a survey to corruption specialist to ask their opinions about the level of corruption in a country
  7. In this type of sampling, volunteers are actively searched for or invited to participate. Most of the internet surveys that flood the web also use volunteer sampling.
  8. For example, a cigarette company wants to find out what age group prefers what brand of cigarettes in a particular city. They apply survey quota on the age groups of 21-30, 31-40, 41-50, and 51+. From this information, the researcher gauges the smoking trend among the population of the city.
  9. One of its advantages is that the interviewer can also examine the interviewer’s non-verbal behavior and draw some conclusions from this. The interviewer can also explain the question in more detail.
  10. The main difference between personal and phone interview is logistics. The interviewer does need to travel to meet the respondents.
  11. The respondent must cope with the questionnaire herself; she only sees the questions and does not hear them; assistance cannot be provided, an there is nobody who can clarify unclear questions or words.
  12. In this case, the pre-test can be part of the interviewer’s training.