This study compares the file folder structures of two groups: 6 administrative staff and 6 PhD students. It finds that PhD students generally have deeper folder structures, with higher maximum and average depths, than administrative staff. While both groups follow a similar distribution of files per folder known as Zipf's law, PhD students tend to have more files overall and their structures are narrower and deeper compared to administrative staff who have broader but shallower structures. These differences may reflect the more structured nature of administrative work versus the depth of research activities for PhD students.

1. A Quantitative Comparison on File Folder
Structures ofTwo Groups of InformationWorkers
Hong Zhang Xiao Hu
School of Library and Information Science
University of Kentucky*
Faculty of Education
The University of Hong Kong
 Information workers organize and access information in file
folders on computers for daily work and study
• Structure of file folders may be related to task natures
 This study:
 Compares file folder structures of two groups of information
workers, using quantitative measures
 Depth of folder structures are significantly different
 Unequal variance t-tests on the two groups’ maximum
depth (p = 0.043) and average depth (p = 0.032)
 Adm participants generally have shallower folders than the
PhD participants
 12 participants
 6 administrative staff in an academic environment (Adm)
 In the institution from 3 months to 29 years)
 6 Ph.D. students (PhD)
 In programs for 1 to 6 years)
 Folders studied:
 Home folder
 2-4 selected top-level folders, including
 a current working project
 a completed or archived project
 miscellaneous files
Ave. Depth Max. Depth
Mean Stdev Mean Stdev
Adm 2.50 0.44 4.00 1.10
PhD 5.12 2.18 9.17 4.71
 Fisher’s Exact Test shows the difference between the two groups
is significant at the 90 percent confidence level (p = 0.06)
 PhD group had much more files than the Adm group
 Both groups follow Zipf’s law
 Exponent values of 1.30 for Adm and 1.27 for PhD
 Frequencies decrease at similar speed
 Most folders contain small number of files
 A larger number of folders with single files
 intuitively single file folder is less efficient
 Different characteristics of folder structures may reflect the scale
of administrative activities and the depth of research
activities done by the two groups of information workers
 The natures of information activities routinely conducted by
the users should be taken into account in investigating personal
digital document organization
File folder
structures
 Adm group had broader tree structures than the PhD group
 Adm group has larger inter-variation than the PhD group
 Both: most of the participants had median values of 1 or 2; and
mode values of 1 or 2
 Most folders have only 1 or 2 subfolders
#. of Subfolders #. of Subfolders per folder
Total Mean Stdev
Adm 691 8.13 5.73
PhD 3,127 3.40 0.39
Breath > Depth Breath < Depth
Broad and Shallow Narrow and Deep
Adm 4 people 2 people
PhD 0 people 6 people
#. of Files #. of Files per Folder
Total Median Mode Mean
Adm 6146 4 1 10.87
PhD 35,721 4 1 8.92
0
100
200
300
400
500
600
700
800
0
4
8
12
16
20
24
28
32
36
40
44
48
53
57
63
67
72
80
85
91
99
103
Frequency
Number of files in a folder
Adm PhD
structured tasks
unstructured tasks
Administrative Research
Ph.D
student
Design
student
Assistant
professor
HR
manager
(Bondarenko &
Janssen, 2005)
*: the affiliation when the research was conducted