An Empirical Study on the Risks of Using Off-the-Shelf
Techniques for Processing Mailing List Data
Nicolas Bettenburg, Emad Shihab, Ahmed E. Hassan
Queen’s University, Canada
1

Development Repositories
SOURCE COMMUNICATION BUG
CODE ARCHIVES DATABASES
2

Development Repositories
SOURCE COMMUNICATION BUG
CODE ARCHIVES DATABASES
3

The Importance of Mailing List
Archives
rm of comm unication
• Emai l popular fo
to distribu te messages
• Mailing lists
valuable in formation
• Messa ges contain
ssions of s ource code
• Discu
evelopmen t decisions
•D
• Er ror reports
ser support requests
•U
4

Mining the Mailing Lists of
23 Open-Source Projects
• Summarizing developer mailing lists
• Using off-the-shelf tools
• Data from around 500,000 emails
• Unexpected results from experiments
5

catter !! things !! info !! mlw !! bool !! palloc(bufsize); !! symlinks !! configuration
! Nov !! --- !! && !! NULL, !! reasonable. !! -r !! argv, !! Added !! reasons !! A1 !! http://w
! > !! break; !! get !! SIGNATURE !! -----END !! != !! symlinks. !! command !!
! char !! 1F !! file !! postgres !! Dec !! 43 !! DataDir, !! pg_hba.conf !! 69 !! + SetData
! -- !! 093E !! stuff !! -D !! switch !! NULL !! +extern !! recursion !! admin !! setting !! 5B
path/default.conf !! see !! overides !! http://xyzzy.dhs.org/~drew/ !! + /* !! (char !! -p !! sizeof(ch
"datadir" !! running !! PGP !! (GNU/Linux) !! "hbaconfig" !! file. !! ((opt !! 2001 !!
! bits !! simple !! databases !! */ !! servers !! multiple !! /* !! share !! "A:a:B:b:c:D:d:Fh:ik:lm:M
#include !! *) !! vendors !! E3 !! people !! + { !! 08:27:06 !! 3B !! 16 !! +# !! explic
malloc(strlen(DataDir)!! +++ !! !! v1.0.6 !! having !! 56 !! /etc. !! 613-389-5481 !! extern !! case
diff !! easier !! certs !! given !! { !!
6

nfiguration !! PGDATA mlw !! bool !! palloc(bufsize);!!!!long !! environment !! agrees ! resides. !
catter !! things !! info !!
!! impose !! them. !! opinion !! keys
symlinks !! configuration
eating !! exactly !! postgresql !! original !! stuff !! described !! (My !! say !! "pg" !! BSD !
! Nov !! --- !! && !! NULL, !! reasonable. !! -r !! argv, !! Added !! reasons !! A1 !! http://w
!
!
specifies
> !! certs !! data !! Tux !! looks !! policy, !! '/etc/pgsql/pg_hba.conf' !!
!! break; !! get !! SIGNATURE !! -----END !! != !! symlinks. !! command !!
attered !! patch !! layout !! linux, !! '/u01/postgres' !! give !! path !! all. !! file. !! live !! belongs, !
! char !! 1F !!
ecified, !! hey, !!
file !! !! reasons !! it. !!
reasonable.
!! Dec !!
postgres 43
damn !! options: !! utterly !! line, !! files !!
!! DataDir, !! pg_hba.conf !! 69 !! + SetData
co
! -- !! 093E !! stuff !! -D !! switch !! NULL !! +extern !! recursion !! admin !! setting !! 5B
hod options
!! considering !! always. !! !! symlinks. !! different !! 5434 !! /etc/pgsql/
path/default.conf !! see !! overides !! http://xyzzy.dhs.org/~drew/ !! + /* !! (char !! -p !! sizeof(ch
postgresql PGP !! !!(GNU/Linux) !! !! !! file. !! ((opt !! 2001 !!
"datadir" !! !! !!
running
things !!overides !! convenient !!
using, symlinking
"hbaconfig"
ab
onf !! command !! !! */ !! !! !! multiple !! !!/* !! share !!!! !!
! !!
bits !! databases
simple
!! controllable modssl
servers
!!
undesired /path/name3" ","I Similarly, ObFlam
"A:a:B:b:c:D:d:Fh:ik:lm:M
ster !! Config !! directory!!!!+ { !!
#include !! *) !! vendors !!
!! people E3
discussion !! packager !! ass. !! really !! machine !!
08:27:06 !! 3B !! 16 !! +# !! explic
!! +++ !! !! /etc/nessusd. !! logical. !! behavior !! crypto !!
evil !! sense !! hbaconfig
malloc(strlen(DataDir)
diff !! easier !! certs !! given !! { !!
Debian
!! v1.0.6 !! having !! 56 !! /etc. !! 613-389-5481 !! extern !! case
g !! kinda !! see !! forced !! people !! pg_hba.conf ! !! pgdatadir !! /path/name2 !! guess !! get !! o
6

While mining Mailing Lists of
23 Open-Source Projects
• Don’t treat mail archives as textual data
• Changing technologies
• Up to 98% of messages contain noise
7

While mining Mailing Lists of
23 Open-Source Projects
• Don’t treat mail archives as textual data
• Changing technologies
• Up to 98% of messages contain noise
Additional processing and cleaning needed!
8

From geek+@cmu.edu Wed Jan 21 08:11:26 1998
Date: Mon, 27 Jan 1997 12:50:44 -0500 (EST)
From: "Brian E. Gallew" <geek+@cmu.edu>
Subject: Re: [HACKERS] configure
- ---559023410-851401618-854387445=:824
Content-Type: TEXT/PLAIN; CHARSET=US-ASCII
> If you can grab a copy and run it on your machine, and send me
> the output, that would help alot.
Here is a gzip'ed tar of the results.
=====================================================================
| Please do not shoot at the thermonuclear weapons! -- Deacon |
=====================================================================
| Finger geek@andrew.cmu.edu for my public key. |
=====================================================================
- ---559023410-851401618-854387445=:824
Content-Type: APPLICATION/x-gzip
Content-Transfer-Encoding: BASE64
Content-Description: m88k-dg-dgux5.4R3.10.tar.gz
H4sIAHDq7DICA+xba3vaSLLOV/MrepzsGHiQuNomOJ4MdnDMrC8csB17HQ8W
UgM9FpJWFxsmyX8/Vd0tIYGwye5kP+w5fp4EaHW9XV1dXbdu6bY1ZCNV1/Qx
ffWD/sql0k6tRl4RUq6IT1KWn4R/L5UI2ansVirVSrlWhpZqqVZ5RUqv/gN/
gedrLiGvHNvzRy71VvUbUYu6mvnqv+zvNbkYM48MmUkJfGrEG1PTJJ7uMscn
9

From geek+@cmu.edu Wed Jan 21 08:11:26 1998
Date: Mon, 27 Jan 1997 12:50:44 -0500 (EST)
From: "Brian E. Gallew" <geek+@cmu.edu>
Subject: Re: [HACKERS] configure
- ---559023410-851401618-854387445=:824
Content-Type: TEXT/PLAIN; CHARSET=US-ASCII
> If you can grab a copy and run it on your machine, and send me
> the output, that would help alot.
Here is a gzip'ed tar of the results.
=====================================================================
| Please do not shoot at the thermonuclear weapons! -- Deacon |
=====================================================================
| Finger geek@andrew.cmu.edu for my public key. |
=====================================================================
- ---559023410-851401618-854387445=:824
Content-Type: APPLICATION/x-gzip
Content-Transfer-Encoding: BASE64
Content-Description: m88k-dg-dgux5.4R3.10.tar.gz
H4sIAHDq7DICA+xba3vaSLLOV/MrepzsGHiQuNomOJ4MdnDMrC8csB17HQ8W
UgM9FpJWFxsmyX8/Vd0tIYGwye5kP+w5fp4EaHW9XV1dXbdu6bY1ZCNV1/Qx
ffWD/sql0k6tRl4RUq6IT1KWn4R/L5UI2ansVirVSrlWhpZqqVZ5RUqv/gN/
gedrLiGvHNvzRy71VvUbUYu6mvnqv+zvNbkYM48MmUkJfGrEG1PTJJ7uMscn
10

Resolving Multiple Sender Identities
• Participants send mail from different addresses
• Up to 21% of addresses are aliases
• Such aliases bias identity-based analyses
• Manual inspection and correction tedious
• No fully automated approach to resolve identities
11

Reconstructing Discussion Threads
• Mail stored sequentially in archives
• Logical grouping: discussion topics
• Required information erroneous or missing
• Essential for social network and topic analysis
A A
B B
C C
D D
Linear Sequence Thread Hierarchy
12

From geek+@cmu.edu Wed Jan 21 08:11:26 1998
Date: Mon, 27 Jan 1997 12:50:44 -0500 (EST)
From: "Brian E. Gallew" <geek+@cmu.edu>
Subject: Re: [HACKERS] configure
- ---559023410-851401618-854387445=:824
Content-Type: TEXT/PLAIN; CHARSET=US-ASCII
> If you can grab a copy and run it on your machine, and send me
> the output, that would help alot.
Here is a gzip'ed tar of the results.
=====================================================================
| Please do not shoot at the thermonuclear weapons! -- Deacon |
=====================================================================
| Finger geek@andrew.cmu.edu for my public key. |
=====================================================================
- ---559023410-851401618-854387445=:824
Content-Type: APPLICATION/x-gzip
Content-Transfer-Encoding: BASE64
Content-Description: m88k-dg-dgux5.4R3.10.tar.gz
H4sIAHDq7DICA+xba3vaSLLOV/MrepzsGHiQuNomOJ4MdnDMrC8csB17HQ8W
UgM9FpJWFxsmyX8/Vd0tIYGwye5kP+w5fp4EaHW9XV1dXbdu6bY1ZCNV1/Qx
ffWD/sql0k6tRl4RUq6IT1KWn4R/L5UI2ansVirVSrlWhpZqqVZ5RUqv/gN/
gedrLiGvHNvzRy71VvUbUYu6mvnqv+zvNbkYM48MmUkJfGrEG1PTJJ7uMscn
13

From geek+@cmu.edu Wed Jan 21 08:11:26 1998
Date: Mon, 27 Jan 1997 12:50:44 -0500 (EST)
From: "Brian E. Gallew" <geek+@cmu.edu>
Subject: Re: [HACKERS] configure
- ---559023410-851401618-854387445=:824
Content-Type: TEXT/PLAIN; CHARSET=US-ASCII
> If you can grab a copy and run it on your machine, and send me
> the output, that would help alot.
Here is a gzip'ed tar of the results.
=====================================================================
| Please do not shoot at the thermonuclear weapons! -- Deacon |
=====================================================================
| Finger geek@andrew.cmu.edu for my public key. |
=====================================================================
- ---559023410-851401618-854387445=:824
Content-Type: APPLICATION/x-gzip
Content-Transfer-Encoding: BASE64
Content-Description: m88k-dg-dgux5.4R3.10.tar.gz
H4sIAHDq7DICA+xba3vaSLLOV/MrepzsGHiQuNomOJ4MdnDMrC8csB17HQ8W
UgM9FpJWFxsmyX8/Vd0tIYGwye5kP+w5fp4EaHW9XV1dXbdu6bY1ZCNV1/Qx
ffWD/sql0k6tRl4RUq6IT1KWn4R/L5UI2ansVirVSrlWhpZqqVZ5RUqv/gN/
gedrLiGvHNvzRy71VvUbUYu6mvnqv+zvNbkYM48MmUkJfGrEG1PTJJ7uMscn
14

Attachments
• MIME standard defines extensions to email
• Binary data encoded as text
• Around 10% of messages have attachments
• Extract attachments and store separately
15

From geek+@cmu.edu Wed Jan 21 08:11:26 1998
Date: Mon, 27 Jan 1997 12:50:44 -0500 (EST)
From: "Brian E. Gallew" <geek+@cmu.edu>
Subject: Re: [HACKERS] configure
- ---559023410-851401618-854387445=:824
Content-Type: TEXT/PLAIN; CHARSET=US-ASCII
> If you can grab a copy and run it on your machine, and send me
> the output, that would help alot.
Here is a gzip'ed tar of the results.
=====================================================================
| Please do not shoot at the thermonuclear weapons! -- Deacon |
=====================================================================
| Finger geek@andrew.cmu.edu for my public key. |
=====================================================================
- ---559023410-851401618-854387445=:824
Content-Type: APPLICATION/x-gzip
Content-Transfer-Encoding: BASE64
Content-Description: m88k-dg-dgux5.4R3.10.tar.gz
H4sIAHDq7DICA+xba3vaSLLOV/MrepzsGHiQuNomOJ4MdnDMrC8csB17HQ8W
UgM9FpJWFxsmyX8/Vd0tIYGwye5kP+w5fp4EaHW9XV1dXbdu6bY1ZCNV1/Qx
ffWD/sql0k6tRl4RUq6IT1KWn4R/L5UI2ansVirVSrlWhpZqqVZ5RUqv/gN/
gedrLiGvHNvzRy71VvUbUYu6mvnqv+zvNbkYM48MmUkJfGrEG1PTJJ7uMscn
16

From geek+@cmu.edu Wed Jan 21 08:11:26 1998
Date: Mon, 27 Jan 1997 12:50:44 -0500 (EST)
From: "Brian E. Gallew" <geek+@cmu.edu>
Subject: Re: [HACKERS] configure
- ---559023410-851401618-854387445=:824
Content-Type: TEXT/PLAIN; CHARSET=US-ASCII
> If you can grab a copy and run it on your machine, and send me
> the output, that would help alot.
Here is a gzip'ed tar of the results.
=====================================================================
| Please do not shoot at the thermonuclear weapons! -- Deacon |
=====================================================================
| Finger geek@andrew.cmu.edu for my public key. |
=====================================================================
- ---559023410-851401618-854387445=:824
Content-Type: APPLICATION/x-gzip
Content-Transfer-Encoding: BASE64
Content-Description: m88k-dg-dgux5.4R3.10.tar.gz
H4sIAHDq7DICA+xba3vaSLLOV/MrepzsGHiQuNomOJ4MdnDMrC8csB17HQ8W
UgM9FpJWFxsmyX8/Vd0tIYGwye5kP+w5fp4EaHW9XV1dXbdu6bY1ZCNV1/Qx
ffWD/sql0k6tRl4RUq6IT1KWn4R/L5UI2ansVirVSrlWhpZqqVZ5RUqv/gN/
gedrLiGvHNvzRy71VvUbUYu6mvnqv+zvNbkYM48MmUkJfGrEG1PTJJ7uMscn
17

Quotes and Signatures
• Duplicate information
• Unrelated to actual message
• Removing signatures is challenging
• Quoted text may or may not be desirable
• Signatures impact text mining approaches
• No perfect method for signature removal
====
=== ==== |
= ==== n
===
==== -- Deaco =======
==== ==
= ==== eapons! ==== |
=== ==== ear w === ====
==== rmonucl ==== ===
=== == e === == === ====
=== ==== t the th ======= key . === ====
=== ==== shoot a === ==== pub lic === ====
=== ==== do not === ==== fo r my ========
ase ==== cmu.edu ===
| Ple === ==== rew. === ====
==== eek@and ====
==== er g ====
===
ng ==
| Fi ========
==
====
18

More Risks presented
in the Paper
19

(1) Mailing Lists contain valuable
information on a project.
(2) Data Needs Pre-Processing before
applying traditional tools.
(3) Manual Data Processing is often not
feasible or requires much effort.
(4) Off-the-Shelf tools were not designed
to prepare data for mining.
20