Title: Descriptive Data Analysis: Analyzing Survey Data
1Descriptive Data AnalysisAnalyzing Survey Data
- Research Methods for Public Administrators
- Dr. Gail Johnson
2At Long Last Analyzing Surveys
- Surveys Using Percent Distributions
- Key Topics
- Handling Exits
- Analyzing 5-point scales
- Extreme analysis
- Handling the middle categories
3Guidelines for Exits
- Exit options on scales
- dont know
- not applicable
- no opinion
- Handling Exits no firm rules
4Guidelines for Exits
- Key decision leave in or exclude from analysis?
- If the number of people taking an exit is very
small, there will be little difference in the
percent distribution so the researchers only need
to inform the reader whether they are included or
excluded
5Handling Exits
- If there is a high percent of exits, does it make
sense? If it does, exclude from the analysis - For example, if you ask people how satisfied or
dissatisfied they are with the zoning office, a
high percent might say not applicable. - That might make sense because probably only a
small proportion of citizens contact the zoning
office in any given year. - The not applicable responses could be excluded,
and the analysis should focus on the percent
distribution who actually answered in the
satisfieddissatisfied scale.
6Handling Exits
- If, on the other hand, there is a high proportion
of people taking the exits for reasons that are
not clear, the researchers might want to spend
some time to figure that out. - It could be a sign that there was a problem with
the question. - My best adviceas a general rulewould be to
exclude the exits from the analysis, and focus on
only those who answered within the scale.
7Handling Exits
- Make sure the analysis is anchored in terms of
the number of people who answered within the
scale. - Of the 300 people who indicated their level of
satisfaction, 65 reported being very or somewhat
satisfied.
8Analyzing Survey Scales
- Decision rules for 5-point scales
- Very Satisfied
- Somewhat satisfied
- Neither
- Somewhat dissatisfied
- Very dissatisfied
9Analyzing Survey Scales
- Decision rules for 5-point scales.
- I first look at where a majority (50 or more)
answered either on the positive or the negative
side of the scales. - Very satisfied and somewhat satisfied.
- Very dissatisfied and somewhat dissatisfied.
- It allows me summarize the set of questions
- Of the 5 questions about the city services, a
majority reported being very satisfied or
somewhat satisfied with library services,
recreation department and the fire department.
10Analyzing Survey Scales Extreme Analysis
- If a majority answered positively or negatively
on many questions, I then do an extreme
analysisthat is, I look for questions where a
majority answered very satisfied or very
dissatisfied. - It is unusual to get a majority at the extreme
end of scale, so that information shows the
greatest intensity of feeling about the issue.
11Exercise Whats The Story About Faculty
Performance?
12Exercise Whats The Story?
- What are students most satisfied with?
- What are students least satisfied with?
- Whats the story the data tells?
13Analyzing Survey Scales
- A majority was very satisfied or generally
satisfied with all four aspects of faculty
performance. - However, a majority (54) were very satisfied
with faculty knowledge. - Part of analyzing the data requires identifying
the key elements of the story. - I would highlight faculty knowledge as being a
strong aspect of faculty performance according to
those completing the survey.
14Handling the Middle Category
- As you know, I like uneven scales (scales with 5
or 7 choices). - For example, Likert scales have a neutral middle.
- Neither agree or disagree.
- Combining the neither category with the agree
side or the disagree side clearly does not make
any sense.
155-point Scale Without a Neutral Middle (one-way
scales)
- ___ Almost Never/Never
- ___ Seldom
- ___ Occasionally
- ___ Usually
- ___ Almost Always/Always
- Note a graduated one-way scale with soft-ends
16Handling the Middle Category
- Another common one-way scale
- Very great extent
- Great extent
- Moderate extent
- Some extent
- Little of no extent
17Handling the Middle Category in One-way Scales
- It is possible to combine categories when using a
scale without a neutral middle, - It could be honestly reported that 90 percent of
the respondents rated the city services as
helpful to at least some extent. - However, the researcher is rolling 4 of the 5
possible categories togetherand raises a
question of whether the researcher is trying to
hide the detail. Maybe very few respondents
provide favorable ratings.
18Handling the Middle Category in One-way Scales
- My advice the middle category stands alone, even
though it is not neutral. - It is too easy to distort the data by combining
the middle category with either side of the scale
to make it say what the researcher wants.
19Handling the Middle Category in Goldilocks Scales
- Does the program offer too many, too few are just
about the right number of electives - Much too many
- Somewhat too many
- Just about right
- Somewhat too few
- Much too few
20Handling the Middle Category in Goldilocks Scales
- The middle category is not neutral it contains
important information. - In fact, the program director would be hoping
that most people say just about right - It too stands alone!
21Handling the Middle Category
- My rule the middle always stands alone.
- Let me repeat the middle stands alone.
22Why Not Have Yes or No Scales?
- Or even scales?
- I prefer 5-point scales because it gives me the
option of looking at the extreme ends of the
scales. - If I only ask people whether they are satisfied
or dissatisfied, I do not know how many are
really very satisfied as compared to somewhat
satisfied. - The difference in intensity might be important.
23Why Not Have Yes or No Scales?
- I still have the option of collapsing the 2
positive together and 2 negative sides of the
scale together to simply reporting. - The middle category gives a place for people to
go if they really do not have an opinion one way
or the other. - Some people do not like to say they dont know,
so they find a middle category.
24Key Questions About Survey Results
- Make sure you know the decision rules did the
researchers exclude the people answering dont
know? - Did they do an extreme analysis?
- How many categories did they roll together to get
their results? - Did they maintain the neutral middle?
25Final Words on Analyzing Survey Data
- Be mindful of words like most peopledo they
mean the majority (50) or do they mean a
plurality (the greatest proportion but less than
a majority). - When working with survey data, round percentages
to the nearest whole number (.5 and up, round up,
less than .5, round down). - Decimal points can give a false sense of
precision and make it harder for people to
remember the numbers.
26Creative Commons
- This powerpoint is meant to be used and shared
with attribution - Please provide feedback
- If you make changes, please share freely and send
me a copy of changes - Johnsong62_at_gmail.com
- Visit www.creativecommons.org for more information