we know where you should work next summer: job recommendations
TRANSCRIPT
We know where you
should work next
summerJob Recommendations
September 2015 @RecSys
Fabian Abel, http://xing.com
We know where you
should work next
summerJob Recommendations
September 2015 @RecSys
Fabian Abel, http://xing.comAt XINGin Hamburg, Barcelona, Vienna
or somewhere remote…
ChallengeIdentifying job postings that match the demands of the user and employer
3
Job
Recommender
0.92 0.8 0.76
…
User
Job postingsEmployer
Job postings on XING
7
Title
Company
Employment type
and career level
Full-text
description
Key properties of a job posting
Key sources for understanding user demandsExploiting patterns that are found in the data(graph)
8
Social Network
explicit and
implicit
connections
Profile
Fabian Abel
Data Scientist
Haves:
Interests:
web science
big data, hadoop skills & co.
Interactions
data
web
social media
clicks, shares,
ratings
big data
kununu
Interactions of
similar users
similar usershadoop
scala
Social Network
explicit and
implicit
connections
Profile
Fabian Abel
Data Scientist
Haves:
Interests:
web science
big data, hadoop skills & co.
Interactions
data
web
social media
clicks, shares,
ratings
big data
kununu
Interactions of
similar users
similar usershadoop
scala
Relevance EstimationFinal relevance score of an item is obtained by combining the
scores coming from the “sub-recommenders” (= features)
9
Content-
based
features
Collaborative
features
Social
features
Usage
behavior
features
Relevance
Estimation(regression model)
Logistic Regression
P(relevant | x) = 1
1 + e -(b0 + bi xi)i
n
feature vector impact of feature xi
Relevance Estimation + Additional FiltersFiltering (rules) may dampen the relevance scores or filter out items
10
Content-
based
features
Collaborative
features
Social
features
Usage
behavior
features
Relevance
Estimation(regression model)
Location-
based
filtering
Content-
based
diversification
Monetary-
based
diversification
Career Level
filtering
Filtering &
Diversification
0.92 0.8 0.76
…
past
past
Profile describes a
user‘s past/current
position(s), not her
future career step(s)
Career path patterns: locationsDistance between user and location of bookmarked job postings on XING
11
0-50 km
35%
51-200 km
22%
>200 km43%
Career path patterns: career levelsClimbing up the ladder (based on 15M XING CVs)
12
junior
junior
senior
manger
senior manger
today
Next
ste
p
53%
senior
72%
manger
54%
senior manger
52%
Career path patterns: job rolesMost users switch at least once from one job role to another
13
Postdoc
Manager
Lecturer
Postdoc
Professor
6%
5%
3%
2%
Career path transitionsUnderstanding transitions in the career path graph
14
Web Developer
J2EE Developer
Data Scientist
Machine Learning Expert
MSc Computer Science
CV:
MSc Computer
Science
Web Developer
J2EE
Developer
Data Scientist
Machine
Learning
Expert
Data Scientist
Machine Learning Expert
PhD Data Mining
CV:
J2EE Developer
Data Scientist
Machine Learning Expert
MSc Computer Science
CV:
PhD Data
Mining
Career path graphWeighted directed graph with different types of nodes (job roles, education)
15
Association rule mining for constructing
the career path graph:
• Association rules (= edges):
Job role A Job role B
Education X Job Role Y
...
• Minimum support (e.g. at least k
transitions with A and B have to occur in
the data)
• Minimum confidence (= probability(B | A)
= weights of edges)
MSc Computer
Science
Web Developer
J2EE
Developer
Data Scientist
Machine
Learning
Expert
PhD Data
Mining
Similarly, graphs are constructed for:Jobrole X Industry Y
Career Level X Career Level Y...
Thresholds for min-support and min-confidence need to be learned (per
“discipline”)
Inferring Features from Career path graph(s)Probabilities that the job role is appropriate for the user
16
User
Machine
Learning
Expert
PhD Data
Mining
Job posting
Data
Scientist
P( | , )Data
Scientist
Machine
Learning
Expert= 0.79F2:
PhD Data
Mining
P( | )Data
Scientist
Machine
Learning
Expert= 0.52F1:
Features:
P( | , )Data
Scientist
Machine
Learning
Expert= 0.6F3:
5 years
experience
…
Career
path
graph
Impact of Career Path featureAB test with 50:50 split, >10M impressions
CTR
Control group
Group with Career path feature
?
+8%
2%
1%
18
futureme.xing.comfutureme.xing.com
spin-off project which allows for
browsing the career-path graph