Text analysis software needs more common sense and less

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Conference September 2013
Text analysis software needs more
common sense and less
intelligence!
John S. Lemon, University of
Aberdeen
1
Open Day 2013
IT Services
John S. Lemon
Student Liaison Officer
Introduction
• History – setting the scene
• Problem – move from quantitative to
qualitative
• Etc.
Introduction
•
•
•
•
•
History – setting the scene
Problem – move from quantitative to qualitative
How - Analysis / reporting
Quantity – increases each year
Constraints
– Reports required earlier each year
– Very limited budget
4
Disclaimer
• I am not a statistician – I just have to present
reports
• When I started at university in 1975 almost all
data was numeric / quantitative
• For the purposes of this paper I emulated a naive
user
• To carry out the analysis there is no budget for:
– Software
– Training
5
History
• IT Services ( formerly DISS & DIT ) runs an
annual survey to:
– Staff
– Students
• Purpose is to identify satisfaction with facilities
and service
• Originally on paper and scanned – almost
entirely tick boxes
• Moved to web but retained ‘tick box’ format
6
History
• Converted to WebHost around 2008/9
• Still retained the mainly quantitative original
7
History
• SNAP had been used to create Student Course
Evaluation Forms ( SCEF )
• On paper since 1999 – two sides of Likert scales
• Only one free text box
• 60,000 forms scanned / year
• In 2010 deemed to be ‘not green’ / ecological
• Move to special web based software
• Move to free text comments
8
History
• This is the 2007 paper form
• As SCEF forms had changed
approach it was decided the
annual survey would do the
same
• Fewer tick boxes
9
History
• From 2011 some check boxes but more free
text options.
10
Problem - quantitative to qualitative
• Report generation could no longer rely on
– charts
– tables.
• No thought given to how to cope with free text
• First year one person (me)
– ‘skimmed’ the responses
– Subdivided according to which area of service was
commented on
– Passed to section heads for action and responses
11
Problem - quantitative to qualitative
• Second year – manual coding
• Excel file of case number and free text comments
• Plus extra columns for coding comments /
categorisation
• Code values were “Positive”, “Negative” or
“Ambiguous”
• Limited number of categories
• Needed consistency so one person coded all
12
Problem - quantitative to qualitative
• Once coded loaded into SPSS
• Merged with original file
• Produced tables and charts combining
demographic data and coded values
• Extremely labour intensive
• Needed an iterative approach for accuracy
– Categories were too broad or too detailed
– Codes were too restrictive
13
Problem - quantitative to qualitative
• This year attempted a new approach
• Use software
• New / updated versions of:
– SNAP (11)
– Nvivo (10)
– STAFS - SPSS Text analysis For Surveys (4)
• Also consider use of concordance software
14
Problem - quantitative to qualitative
• Why choose these four products ?
– SNAP
• Already had so no extra cost
• Had SNAP format files so no translating / transforming
the data
– NVivo
• Like SNAP already had on site
• Claims that it would meet all requirements
• Takes data from many sources
15
Problem - quantitative to qualitative
• Why choose these four products ?
– SPSS Text Analysis For Surveys
• Reads SPSS files which SNAP would create
• Export coded categories back to SPSS
• Being considered for site licence
– Concordance
• Language / literature department recommendation
• Cheap
• Appeared easy to use.
16
SNAP
• Survey had been done in SNAP so tried first
• New features are:
– word ‘cloud’
– Auto coding of text / words
• Can combine all the free text questions into one
new ‘derived’ / auto-recoded variable
17
SNAP
• Not very helpful
• Is there a
difference
between
‘computer’ and
‘computers’ ?
Word cloud of Free text comments
MyAberdeen
university
library
computers
time
students
internet
help
work
staff
access
computer good
Campus
eduroam
service slow
Services helpful
problems
18
SNAP
• Not only ‘computer(s)’ presented problems
• But all the different terms students use for the
wireless network.
• These are the more obvious
spellings – ignoring the
miss-spellings.
• Not ideal as did not allow
for synonyms
19
SNAP - limitations
• Has a ‘Stop’ list – words to exclude
• No equivalent list to create synonyms
• Would like to be able to do:
{wifi,wi-fi,eduroam,resnet,wireless}={wireless}
• Not just a limitation of SNAP word cloud
• In the time available could not find how to export
auto-coded variables to SPSS
20
Concordance
• Cheaper but very limited
• No ability to easily export the results
• Positive point is it shows need for synonyms !!
21
NVivo
• Very powerful
• Accepts data from a wide variety of sources:
–
–
–
–
–
–
Text
Video
Pictures
Web
Social media
Etc.
22
NVivo
• Data needed some pre-preparation before input
• Some of the concepts weren’t obvious
• Took a number of attempts to get the data into
the correct format
• It will combine terms
– But may not be exactly what you want
– Some of the words for ‘connect’ are quite imaginative
to say the least.
23
NVivo
24
NVivo
• Depending on how ‘tight’ or ‘loose’ the word
associations were made could end up with
entirely different results / word clouds
25
NVivo
• Found difficulty in:
– Trying to get the data categorised
– Exporting the results to merge back to SPSS
– Alternatively try and produce tables and charts linked
to demographic data within NVivo
• Problems with all the different software were:
– Time to learn all idiosyncrasies
– Impatient line managers
– Nomenclature
26
STAFS
• Appears to be very powerful and comprehensive
• Very large manual
• Like Nvivio has different nomenclature for the
aspects of analysis
• Will read data from SPSS files
– Providing the text fields are less than 4000 characters
in length
• Looked the most promising to solve the problem
27
STAFS
• Foolishly left it until last for evaluation
• Very little time left to get to grips with yet another
set of concepts
• The deadline for the report was approaching so
not a lot of time
• Also trial version which lasted 14 days
• Appears to have a bit more intelligence in
matching words together
28
STAFS
29
STAFS
• Has the ability to indicate “good” and “bad”
phrases in green, and red
• It also highlights the context in amber
30
STAFS
• Problem is that the file that ‘drives’ this appears
to be rather general in approach
• To really be useful in future it needs tailoring
• Ran out of time to really develop expertise in this
• Potential to apply a level of ‘common sense’
• Not easy to actually do in the time available.
• Export back to merge with SPSS appeared OK
• But had to abandon any further experiments 31
What was used finally
• Time for testing / experimentation had run out
• Only one course of action
– By hand
– One person – me
• Scale of problem
– When loaded into Word as single spaced, normal
margins, 12 pt Calibri
– Just under 500 pages
• A ream of paper
32
Next year
• Try and get a longer trial period for STAFS
• Experiment with this years data to provide coding
file
• Use STAFS from the start
33
Conclusion
• Don’t try and learn a lot of new software when
there are deadlines from “management”
• Word clouds don’t help much
• A concordance really only highlights speeling
idiosyncrasies
• Care must be taken when allowing software to
make choices in coding
34
Conclusion
•
•
•
•
Does text analysis software have intelligence ?
Up to a point
Does it have common sense
Of the four tried only one does
BUT
• It needs teaching “common sense” and that
takes time
• Just like a child !!
35
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