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Sumber : http://www.swap.ac.uk/docs/events/Bradford7.rtf
Types of Questionnaires and Interviews
The types of questionnaires and interviews in the social sciences are designed to meet the specific
objectives of the discreet research. Typically this centres around the size of sample balanced with the
details required from respondents. If the researchers require relatively brief information from a large
number of people over a wide geographical area then questionnaires have distinct advantages over
interviews. However, if the research intends to explore the subjective meanings of trauma, then clearly
interviews are the more appropriate method. The following are the types of questionnaire and
interviews currently used by social scientists.
1. Questionnaire impersonally delivered and returned. This is quintessentially a large-scale postal
questionnaire that many of us are familiar with receiving. Often postal questionnaires are from
marketing companies or organisations collecting information for selling financial services. However,
health authorities, police authorities or academic researchers also use postal questionnaires. Postal
questionnaires, as we shall see, are able to reach a very high sample regionally, nationally and
occasionally international. The most famous `questionnaire' in the UK is the government's Census that
legally compels UK subjects to provide a host of details about their lives.
2. Questionnaire personally delivered. For most research, including research by students, it is neither
necessary nor desirable to use postal questionnaires (there are often problems and expense associated
in obtaining lists of names and addresses of respondents). Researchers instead will personally deliver
questionnaires, either pushing them through the letterboxes of a target population or distribute them to
people using a specific organisation. The respondent will then return the questionnaire by using a
return addressed envelope or use a return box located at the agency. For instance, a student may
require information from people living on a particular housing estate, or, they may distribute
questionnaires to people attending a particular project or agency. The advantage of this is that they do
not require expenditure on postage stamps or envelopes and researchers have a degree of control over
targeting specific people, groups or communities.
3. Questionnaire personally collected. Personally delivered questionnaires still retain the problem of
non-response. The researcher relies on the respondent to return their questionnaire. In order for the
researcher to have some control over the response rate it is sometimes appropriate for the researcher to
collect the questionnaires. This may be done by the researcher calling at a later date or time to collect
the questionnaire at the respondent's home or by returning to a class or session operated by the agency.
This allows the researcher to prompt the respondents to complete and return their answers, thereby
improving the response rate. However, this must be balanced against the time needed to do this and
clearly in a very large survey this is not a feasible option.
4. Telephone interview. It is sometimes easier to not use paper questionnaires that relies on the
vicissitudes of respondents to fill in and return the questionnaire and instead to directly speak to the
target population by telephone. Of course this is premised by the likelihood of a target population
having telephones, for instance, a survey of young homeless people, using telephone interviews will
not be a viable option. It may be difficult to obtain a list of telephone numbers of a target population
and randomly calling people in the hope that they meet the requirements of the research tends to be
very haphazard and expensive. Indeed telephone interviewing is itself expensive compared to postal
questionnaires and far more time consuming for the researcher. Nevertheless telephone interviewing
allows the researcher a relatively high degree of control over the research process and the researcher is
able to speak to respondents directly and clarify any questions or queries the respondent may have on
the interview schedule.
A further note on telephone interviewing is that it allows the responses to be recorded directly on to a
computer. This is technically known as computer assisted telephone interviewing (CATI) and
computers are likely to be used by those people working for marketing companies who ring us up at
home.
5. Face- to-face structured interview (standardised or scheduled interview). For many researchers the
target group of respondents are not suited to the above methods of data collection. They may be
notorious poor respondents (young people for instance), or the time schedule may not allow the luxury
of time for respondents to fill in and return their questionnaires, or they may be limited in number and
the researcher needs an almost perfect response rate for there to be a reasonable sample in which to
apply analysis. Therefore researchers interview them face-to-face and are able to directly control the
return rate in a comparatively quick time and are able to answer any questions. The researcher is also
able to develop trust with the interviewees on the aims of the research and be able to re-assure those
being interviewed over questions of confidentiality and ethics.
It is also worth noting that responses could be directly entered onto a computer for analysis. This
avoids the necessity of recording responses twice and saves time on the `data entry' stage. The use of
computers in face-to-face interviews is called computer assisted personal interview (CAPI).
6. Face-to-face unstructured interview (free or focussed or clinical or depth or nondirective interview).
This method of interview is not usually appropriate for survey methods unless the target group is
particularly small, reticent or vulnerable, this may be appropriate for children or other marginalised
groups. It is appropriate for more `qualitative' approaches where more detailed and subjective data is
required. It is time consuming and is extremely exposed to problems of interviewer bias and
standardising responses (interviewer bias will be discussed in another handout).
7. Group interview or group discussion. This method is very similar to number 6 and shares its
advantages. It shares its disadvantages in relation to survey methods but the problems of bias and
standardising responses is compounded.
8. Natural conversation. The direct opposite to number 1 and has no place in survey research.
As you will probably have noticed as you go down the list from 1 to 8 the method is designed to be
more appropriate for more detailed data for individual respondents. However, the gains in detail are set
against the loss of including a higher sample, where postal questionnaires have the clear advantage in
reaching the highest number of people. Crudely speaking the larger the number of people you include
in your research the more confident you can be of generalisation.
Advantages of Interviews and Advantages of Questionnaires
To briefly summarise the above, the researcher needs to arrive at a decision as to what method they
will use in their survey. Essentially, the researcher must choose between conducting interviews or
distributing a questionnaire. The advantages of doing interviews lie in that they have a higher response
rate, a higher validity in that skilled interviewers can probe the respondent for accurate answers
(however the interviewer must never prompt the respondent) and finally the researcher has a better
degree of control over the research process. However, interviews have a lower reliability in that they
are prone to `the interviewer effect' that is where the interviewer effects the answers given. For
instance, answers given to male and female interviewers are often considerably different. The
interviewer's age, ethnicity and social class have been shown to profoundly effect the type of responses
received.
In contrast questionnaires are cheaper, have periods of time where the researcher is waiting for
responses that can be used for reflection, consideration and further reading around the topic.
Questionnaires have a higher reliability than interviews in that they do not have the problem of
interview effect. However, questionnaires have problems with non-response bias as they have a lower
response rate than interviews. Researchers using questionnaires do not have the opportunity for
probing respondents for clarification of answers and consequently have a lower validity.
Advantages of Interviews
High response rate
High Validity (probes - not prompts)
Low reliability (interviewer effect)
Expensive
Control
Advantages of Questionnaires
Low response rate (non-response bias)
Low Validity
High reliability
Cheap
Time for consideration
Sumber :
http://www.usq.edu.au/library/help/postgrad/resmeth.htm
http://www.tardis.ed.ac.uk/~kate/qmcweb/q2.htm
Closed-ended questions
Name: Dichotomous
Description: Question offering two choices
Example: Did you watch television at all yesterday?
Yes / No
Name: Multiple
Description: Question offering three or more choices
Example: Which of these shops do you prefer?
Next / River Island / Gap Top Shop/ Top Man
Name: Likert scale
Description: Statement with which respondent shows the amount of agreement /
disagreement
Example: Assessment by course-work is easier than assessment by examination
Strongly agree
Agree
Neither agree
nor disagree
Disagree
Strongly
disagree
Name: Semantic differential
Description: Scale is inscribed between two bipolar words and respondent selects the
point that most represents the direction and intensity of his / her feelings
Example: The degree I am taking is.............
Interesting :_____:_____:_____:_____:_____:_____:_____: Boring
Useful :_____:_____:_____:_____:_____:_____:_____: Useless
Easy :_____:_____:_____:_____:_____:_____:_____: Difficult
Name: Rank order
Description: Respondent is asked to rate or rank each option that applies. This allows
the researcher to obtain information on relative preferences, importance etc. Long
lists should be avoided (respondents generally find it difficult to rank more than 5
items)
Example: Please indicate, in rank order, your preferred chocolate bar, putting 1
next to your favourite through to 5 for your least favourite.
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Double Decker
Crunchie
Wispa
Mars Bar
Creme Egg

Open-ended Questions
Open-ended questions
Name: Unstructured
Description: Question that respondents can answer in an unlimited number of ways?
Example: Why did you enrol for this course at QMC / SCOT?
………………………………………………………………………………
………………………………………………………………………………
………………………………………………………………………………
Name: Word Association
Description: Words are presented one at a time and respondents give the first word
that comes to mind
Example: What is the first thing that comes to mind when you hear the following?
Lecture
Computer
Exam
Tutorial
Interesting
Exciting
Challenge
Rewarding
Name: Sentence completion
Description: Incomplete sentences are presented, one at a time, and respondents are
asked to complete the sentence
Example: My worst shopping experience while visiting Tescburys happened
when……………….
Name: Story completion
Description: An incomplete story is presented and respondents asked to complete it
Example: I sat down at the kitchen table, picked up a fork, then looked at the
Chicken and Mushroom flavour Pot Noodles in front of me…….

Advantages & Disadvantages of Closed
and Open-ended Questions
Advantages of Closed-Ended Questions



Quick to answer
Easy to code
No difference between articulate and inarticulate respondents
Disadvantages of Closed-Ended Questions


Can draw misleading conclusions because of limited range of options
Researcher / interviewer cannot deal with qualifications to responses
e.g. "Yes, but….." or "It depends" where only Yes/No are given as
options
Advantages of Open-Ended Questions



Greater freedom of expression
No bias due to limited response ranges
Respondent can qualify their answers
Disadvantages of Open-Ended Questions


Time consuming to code
Researcher / interviewer may misinterpret (and therefore misclassify)
a response
Sumber : http://www.epa.gov/nheerl/arm/surdesignfaqs.htm
A sample survey is a way of collecting information on a subset of the elements of the
target population with the intention of using the information to determine summary
characteristics about the population. The summaries differ from the same summaries
determined from a census in that they contain uncertainty. The uncertainty arises
from the simple fact that not all elements in the target population were visited. How
the sample is selected determines whether it is possible to know the uncertainty of the
estimate.
A sample is any subset of the target population, i.e., any collection of its elements.
Sampling methods may be classified into either probability-based sample methods or
non-probability-based sampling methods. Probability-based methods are discussed in
subsequent sections. Non-probability methods include chunk samples, expert choice
samples, and quota samp
What is a probability sample?
A probability sample is a sample where every element of the target population has a
known, non-zero probability of being selected. That is, it is possible for every
element of the target population to be in the sample. Two important features of a
probability sample are that the probability selection mechanism (1) guards against site
selection bias and (2) is the basis for scientific inference to characteristics of the
entire target population.
Many alternative approaches are available to select a probability sample. Which
approach is used depends on the objectives of the survey, the available auxiliary
information, logistical or operational constraints in conducting the sampling, the
characteristics of the sample frame, and the complexity of the statistical analysis. A
few alternative designs are described below.
Simple random sample. A simple example of a probability sample is one that gives
every sample of a fixed size the same probability of being selected. This is simple
random sampling without replacement. This is the simplest type of probability
sample. Its major advantage is its simplicity not only in design but in statistical
analysis of the survey results. Statistical analyses do not require any special
procedures; consequently, users can analyze the data essentially ignoring the
probability design. In reality the probability design results in the same assumptions
that are used in standard statistical analyses. Its major disadvantage is that the design
does not incorporate any information about the target population which would
improve the efficiency (precision) of the survey and does not necessarily provide a
sample that will address all the survey objectives. Stratified random sample. A
stratified random sample may be the most common probability survey design used.
When auxiliary information is available on the target population or the survey has
multiple objectives, that information can be used to define strata. For example, a
survey conducted over multiple states may have an objective to provide estimates for
each state as well as for all states combined. In addition, it may be operationally
convenient to have the sample for each state be selected independently from other
states. This can be achieved by defining each state as a stratum and then selecting a
simple random sample within each state. Strata may also be defined using a known
characteristic of each element in the target population, i.e., auxiliary data. For
example, streams may be categorized according to Strahler order in a GIS coverage
that serves as the sample frame. Survey objectives may require that approximately an
equal number of samples come from 1st, 2nd, 3rd, and 4th and higher Strahler order
categories. This may be achieved by defining four strata based on the Strahler order
of each stream. A stratified sample can be considered as a set of independent simple
random samples, i.e., each stratum has a simple random sample. Consequently, the
statistical analyses are similar to those of a simple random sample. Each stratum is
analyzed as a simple random sample; then the estimates are combined across the
stratum. The latter step must be completed correctly to avoid biased estimates.
Unequal probability sample. An alternative to a stratified random sample is an
unequal probability sample. An unequal probability sample is achieved by assigning a
probability of selection to each element of the target population, usually depending on
auxiliary information. For example, Strahler order could be used to assign a
probability of selection to each stream segment where 2nd order streams would be
twice as likely to be selected as 1st order streams, 3rd order streams four times as
likely as 1st order, and 4th and higher order eight times as likely as 1st order. This
type of design provides enormous flexibility in designing to meet objectives as well
as a mechanism to increase precision. Their statistical analysis is more complex and
requires that all analyses use weights derived from the unequal probability of
selection.