=Paper= {{Paper |id=Vol-2311/paper_2 |storemode=property |title=Understanding User Behavior in Job and Talent Search: An Initial Investigation |pdfUrl=https://ceur-ws.org/Vol-2311/paper_2.pdf |volume=Vol-2311 |authors=Damiano Spina,Maria Maistro,Yongli Ren,Sargol Sadeghi,Wilson Wong,Timothy Baldwin,Lawrence Cavedon,Alistair Moffat,Mark Sanderson,Falk Scholer,Justin Zobel |dblpUrl=https://dblp.org/rec/conf/sigir/SpinaMRSWBCMSSZ17 }} ==Understanding User Behavior in Job and Talent Search: An Initial Investigation== https://ceur-ws.org/Vol-2311/paper_2.pdf
             Understanding User Behavior in Job and Talent Search:
                           An Initial Investigation
                  Damiano Spina                                             Maria Maistro                                     Yongli Ren
                RMIT University                                           Univerity of Padua                              RMIT University
              Melbourne, Australia                                           Padua, Italy                               Melbourne, Australia
           damiano.spina@rmit.edu.au                                     maistro@dei.unipd.it                          yongli.ren@rmit.edu.au

                  Sargol Sadeghi                                            Wilson Wong                                  Timothy Baldwin
                    SEEK Ltd.                                                SEEK Ltd.                              The University of Melbourne
               Melbourne, Australia                                     Melbourne, Australia                           Melbourne, Australia
              ssadeghi@seek.com.au                                      wwong@seek.com.au                                 tb@ldwin.net

              Lawrence Cavedon                                             Alistair Moffat                                Mark Sanderson
              RMIT University                                      The University of Melbourne                           RMIT University
             Melbourne, Australia                                     Melbourne, Australia                            Melbourne, Australia
        lawrence.cavedon@rmit.edu.au                                ammoffat@unimelb.edu.au                        mark.sanderson@rmit.edu.au

                                                 Falk Scholer                                      Justin Zobel
                                              RMIT University                            The University of Melbourne
                                           Melbourne, Australia                             Melbourne, Australia
                                         falk.scholer@rmit.edu.au                          jzobel@unimelb.edu.au
ABSTRACT                                                                              paid a suitable level of compensation – is a traditional marketplace,
The Web has created a global marketplace for e-Commerce as well                       dominated for many decades by newspaper classified advertising.
as for talent. Online employment marketplaces provide an effective                    Talent search – in which a company or employer seeks candidates
channel to facilitate the matching between job seekers and hirers.                    who might be suitable for a position within their business that is
This paper presents an initial exploration of user behavior in job and                (or might shortly be) available – is a more recent addition to this
talent search using query and click logs from a popular employment                    ecosystem.
marketplace. The observations suggest that the understanding of                           Both job search and talent search have become increasingly
users’ search behavior in this scenario is still at its infancy and that              offered as effective online services: unemployed persons who look
some of the assumptions made in general web search may not hold                       for work online are re-employed about 25% faster than comparable
true. The open challenges identified so far are presented.                            workers who do not search online [7]. In other research, it has
                                                                                      been shown that employees who found their roles online tend to
CCS CONCEPTS                                                                          stay on for longer. More specifically, “exit rates are lowered by at
                                                                                      least 28% when the internet is used as a job search tool” [10]. The
•Information systems →Query log analysis;
                                                                                      scale and reach of these services, and their benefits in terms of both
                                                                                      personal and corporate productivity, make online job and talent
KEYWORDS
                                                                                      search enormously valuable: the global online job/talent search
Job search; Talent search; Employment marketplace                                     market has been recently estimated at $20-30 billion annually.1
                                                                                          As search activities, the job and talent search processes have
1 INTRODUCTION                                                                        different aims to standard web or enterprise information search.
                                                                                      Users of job and talent search services tend to have search needs
The Web has created a global marketplace for e-Commerce and also
                                                                                      with at least some specific parameters (usually including the type
employment. Job and talent search are two complementary sides
                                                                                      of job, even if expressed via an uncontrolled vocabulary, and of-
of the employment marketplace, with both intended to pair people
                                                                                      ten including locational constraints), but may not have a specific
with opportunities. Job search – the process of an individual moni-
                                                                                      document or even employer in mind. Indeed, for a job searcher
toring for opportunities, or seeking fresh employment in roles for
                                                                                      there is an element of “feeling lucky” every time they search, even
which they have the skills and experience and for which they will be
                                                                                      if they enter the same query as they did last week. At the same
Copyright © 2017 by the paper’s authors. Copying permitted for private and academic   time, the psychology of job seekers and hirers also contributes to a
purposes.                                                                             somewhat more recall-oriented searching process than is usually
In: J. Degenhardt, S. Kallumadi, M. de Rijke, L. Si, A. Trotman, Y. Xu (eds.):
Proceedings of the SIGIR 2017 eCom workshop, August 2017, Tokyo, Japan, published
                                                                                      ascribed to web search. The desire to not miss out on a dream job
at http://ceur-ws.org                                                                 or a talented candidate may mean that the users are more engaged
                                                                                      1 http://www.hhmc.com.au/2015/07/examining-the-job-board-market/
                                                                               D. Spina, M. Maistro, Y. Ren, S. Sadeghi, W. Wong, T. Baldwin
SIGIR eCom 2017, August 2017, Tokyo, Japan                                      L. Cavedon, A. Moffat, M. Sanderson, F. Scholer and J. Zobel

with the search process, and invest more time in perusing results          2    JOB AND TALENT SEARCH
listings.                                                                  The datasets used to compute the statistics and the main results
    However, job seekers – unlike patent or legal searchers – are          of our log analysis are described in this section. Note in particular
unlikely to wish to examine all results that satisfy a measure of rel-     that these datasets are distinct for job and talent search, and for
evance. When faced with hundreds of matches for one query, they            web search. They were generated by different search systems in
are instead likely to add refinements, and also adjust their internal      different time periods, for different populations of users, and with
calibration as to what they are seeking. A person who searches             the results presented via different interfaces and pagination. In
for “barista in Melbourne” and is shown hundreds of matching               particular, there are 20 results per page for the job and talent search
position vacancies might well immediately re-query with an added           applications we examine, and 10 results per page in the web search
“salary range” filter, or specify a more precise geographical location.    interface.
This type of search activity is not dissimilar to certain domains of
vertical search such as automobile or real estate sales [14], in which        Logs for Job and Talent Search. SEEK Ltd. (“SEEK” thereafter) is
users are similarly conscious of the high/long-term impact of the          a diverse group of companies, comprising online employment, edu-
decision that is being considered, and may iterate dozens or even          cational, commercial and volunteer businesses which span across
hundreds of times before taking a further step, such as applying for       Australia, New Zealand, South East Asia, China, Brazil, Mexico,
a position, or seeking more information.                                   Africa and the Indian subcontinent. SEEK’s online marketplaces
    Talent search – when a company or organization is searching            are exposed to approximately 4.1 billion people and more than
across resumes and personal descriptions in order to identify candi-       30% global GDP.2 The click and query logs used in this paper are
dates that might be interested in applying for vacant or forthcoming       proprietary data from the Australia and New Zealand employment
positions – is similar to the task of finding an expert [1, 2], although   business of SEEK.3
arguably in a richer environment, since certain factors are likely            The domestic SEEK employment business facilitates candidates
to be more critical (for example, specific experience, or geographic       to find employment opportunities, and helps hirers to find candi-
location).                                                                 dates for advertised roles. Hirers currently pay to have their ads
    In this paper, we present preliminary work comparing users’            posted on SEEK; then, on the job search side, anyone can access
search behavior for job search, talent search and more traditional         these jobs via the search interface at no cost. Candidates also have
web-search. Our purpose is to better understand whether the un-            the option of registering to create profiles which are used to stream-
derlying assumptions we have with regard to user models, ranking           line the job application process. In addition to keywords, a number
factors and success metrics in web search can (or should) hold true        of search facets are made available to the candidates, including a
for job and talent search. Longer-term, our aim is to understand           job classification taxonomy, a location taxonomy, work types, and
what properties of user behaviors, target documents (job ads or            salary ranges. Each job ad is represented by a title, a short descrip-
user profiles) and their summary descriptions lead to users clicking       tion summarized via bullet points, and some meta-data about the
through to the documents and on to job applications or recruitment         job (including posting date, job location, and classification of the
requests. Ideally, this would include an accounting of the different       ad). Relevance and posting date (“newest first”) are the two features
reasons a user may have for posing a job or talent search query.           by which results can be sorted. Candidates click on the job titles in
For example, an unemployed person might be actively job hunting,           the results page if they wish to read the full content of the job ads
whereas someone currently employed might be researching market             or to apply for them.
salaries in order to negotiate within their existing position. Simi-          SEEK also offers hirers the ability to pro-actively search for
larly, a user of a talent search service might be primarily seeking to     candidates via their profiles; this product is known as Talent Search.
understand how competitive the marketplace is at present and try-          Hirers are provided with the option to filter the search results using
ing to decide whether it is even worth commencing a recruitment            a location taxonomy, the work type and salary information from
campaign for a proposed new role.                                          the profiles, companies where a candidate has previously worked,
    The overall goal of such analysis is to improve services to users      an industry taxonomy, and the candidate’s right to work (visa and
via improved matching of positions on offer, improved pools of             citizenship) information. On the search result pages, hirers can
potential candidates being generated, and higher levels of employer        contact the candidates by sending them messages or inviting them
and employee satisfaction. With that objective as our goal, the next       to apply for jobs. These are known as connection methods.
section examines characteristics of user behavior when performing             The datasets used in this paper are in two parts. The first tranche
job and talent search, and compares these to characteristics of web        covers overall queries and the clicks by candidates searching job ads
search behaviors. We use job and talent search click and query             in response to search result pages over a 4-month period between
logs from SEEK Ltd., one of the world’s leading job seeking and            January 2016 to April 2016. This set contains about 140M searches
talent search companies, with over 30 million user visits per month        by job seekers. The second contains about 1.2M searches by hirers
in Australia and New Zealand alone. Our results show some fun-             and the connections that were performed over the same period of
damental differences compared to standard web search behavior.             time.
The following section then outlines some specific research chal-
                                                                              Logs for Web Search. The frequency of click positions for web
lenges in relation to understanding the intents and goals of job and
                                                                           search was computed using the click logs provided by Yandex [11]
talent seekers as they search, and mechanisms to improve search
performance and experience in these two important contexts.                2 http://www.seek.com.au/investor/about-us
                                                                           3 http://www.seek.com.au
Understanding User Behavior in Job and Talent Search:
An Initial Investigation                                                                                                                                                                               SIGIR eCom 2017, August 2017, Tokyo, Japan



                               1.0   ●




                               0.9
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                                                                                                                                                    Job Search                                 10−1
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                                                                                                                                                    Talent Search                                                                Talent Search
                               0.8                                                                                                                                                                                               Web Search
  Normalized Click Frequency




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                               0.0
                                     0                               10                             20                 30              40           50           60                                   101             103              105
                                                                                                          Rank Position                                                                                         Query Rank


Figure 1: Normalized frequency of click positions in talent search                                                                                                     Figure 2: Rank (log) and normalized frequency (log) of queries in
and job search for clicks on the first three pages (20 results per                                                                                                     job, talent and web search.
page), and on the first result of the fourth page, and on the first
page (10 results per page) for web search.
                                                                                                                                                                       early in the ranking are again the ones most likely to be clicked.
                                                                                                                                                                       This tendency is common to all types of searches, job, talent, and
from the Relevance Prediction Challenge.4 The public dataset for                                                                                                       web, and is known in literature as position bias [5, 15]. In the web
Russian-language web search contains 340,796,067 records with                                                                                                          search dataset, the frequency of clicks for the last rank position on
30,717,251 unique queries, retrieving 10 URLs each. We used the                                                                                                        the page (the 10th position) is similar to the frequencies associated
training set, which consists of 5,191 assessed queries corresponding                                                                                                   with the 8th and 9th positions, without the up-tick in activity at
to 30,741,907 records.                                                                                                                                                 the end of the ranking. Web search users also tend to click less at
                                                                                                                                                                       the bottom of the ranking than do the job search and talent search
    Depth of Clicks. In this section we examine the click frequency                                                                                                    users. This difference may be intrinsic, or may be a consequence of
of search results in Search Engine Result Pages (SERPs) for talent,                                                                                                    the user interface in some way.
job and web search. For each rank position, the frequency of clicks                                                                                                       Finally, it can be seen that the slope of the frequency graph is
is computed by aggregating all the queries in the dataset, that                                                                                                        steeper for web search than for job and talent search. This may be
is, number of clicks divided by the total number of impressions.                                                                                                       due to presentation bias, since job results are paginated with 20
For each query, SERPs including at least one clicked result are                                                                                                        documents per page while web result pages contain 10 documents;
considered.                                                                                                                                                            or, as hypothesized in Section 1, it may be an innate difference in
    Figure 1 shows the click probability for talent, job and web search.                                                                                               user behavior. We plan to investigate this further as we continue
The overall pattern is as one would expect, with a considerable                                                                                                        with this project.
emphasis on the first few positions of the first page of results,
followed by a steady decline. On the other hand, what is notable                                                                                                          Query Popularity. We next analyze the distribution of queries in
in both curves is that the distribution is relatively smooth over                                                                                                      the three different datasets. For this analysis, a random sample of
page boundaries. Both hirers and job seekers are more likely to                                                                                                        one million queries was extracted from each one; Figure 2 shows
click the last document in each SERP page than the one before it,                                                                                                      the frequency (normalized by total) of distinct queries for each
but the usual steep drop-off at page boundaries – a disinclination                                                                                                     subset using, log-log scales.
to load the next page at all – is not present. Another interesting                                                                                                        The figure shows that the top frequent queries in job search
observation is that hirers carrying out talent search activities tend                                                                                                  occur substantially more often than in talent and web search. The
to be more persistent and explore further down subsequent pages                                                                                                        frequency in job search queries starts decreasing faster than in web
than do job seekers in the job search context.                                                                                                                         and talent search. The rightmost values plotted for the three curves
    Figure 1 also provides the corresponding frequency of clicks for                                                                                                   relative to the horizontal axis indicate the different number of
each rank position across the Yandex web search dataset. Positions                                                                                                     unique queries across the three dataset samples. The total number
                                                                                                                                                                       of distinct queries is substantially lower for talent and job search
4 http://imat-relpred.yandex.ru/en/                                                                                                                                    than for web search (note that the figure is in log-scale). This
                                                                               D. Spina, M. Maistro, Y. Ren, S. Sadeghi, W. Wong, T. Baldwin
SIGIR eCom 2017, August 2017, Tokyo, Japan                                      L. Cavedon, A. Moffat, M. Sanderson, F. Scholer and J. Zobel


                                                                           3   FUTURE CHALLENGES
                                   100                      ●
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                                                                           The observations above show that job and talent search have differ-
                                                                           ent characteristics from standard information search tasks. Hence,
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                                                                           existing click models and evaluation frameworks designed primar-
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                                                                           ily for web search may not translate to this domain. For both job
                                                            ●
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  Num. Distinct Queries per User




                                                            ●
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                                                                           and talent search, the quality of a result tends to be significantly
                                                            ●
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                                   75                       ●
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                                                                           more nuanced and important, hence: (1) searchers (job seekers or
                                                            ●
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                                                                           hirers) tend to filter results more carefully; (2) searchers care about
                                                            ●
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                                                                           the “freshness” of results (that is, results not previously seen) for a
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                                             ●
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                                                                           given query; (3) certain aspects of a query have different weights
                                   50        ●

                                                                           (for example, location). Overall, searchers tend to spend more time
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                                             ●
                                                                           on examining a set of search results, and will pose more queries for
                                                                           a given need.
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                                                                              Specific questions to be investigated for this class of search prob-
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                                   25
                                                                           lems include:
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                                                                                 • Are click models used for web search [3] applicable to job
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                                                                                   search? Are the biases observed in web search for clicks
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                                    0                                              also occurring in job search?
                                                                                 • How can user behaviour and user satisfaction be modelled
                                         Job Search   Talent Search
                                                                                   from analyzing interactions in job search logs? [9, 13]
                                                                                 • How should job search be evaluated? Can job seeking
                                                                                   evaluation models [6, 8] inform the evaluation of job search
Figure 3: Query diversity within users for job and talent search.                  engines?
                                                                              Click models [3] are valuable to describe behavior of web users
suggests that the long tail effect is less pronounced in the specialized   by defining a set of rules in order to simulate user interactions with
employment domain.                                                         the search system. These models have a wide range of application
   In fact, the total number of unique queries in the samples from         in Information Retrieval, including predicting user clicks for A/B
the job and talent search logs correspond to the 15% and 20% of the        testing experiments, inferring document relevance and defining
number of distinct queries in the same-sized web search sample,            click based evaluation metrics.
respectively. That is, the queries submitted by job seekers or hirers         Finally, a searcher may have different goals for posing the same
are substantially less diverse than the queries submitted by users         query: for instance, in a job search portal, a user may be a genuine
of a web search engine. This trend is similar to that observed by          job seeker or may just be monitoring the market to research salary
Jansen et al. [4], who compared job-related queries to the entire          ranges for certain positions (this may also be done by a talent
set of queries submitted to a commercial web search engine. They           seeker). An evaluation framework should consider such differences
found that around 60% of the job-related queries used the 100 most         in order to properly account for user search intent and thereby
frequently occurring terms, whereas in the entire set the proportion       effectively measure the success of the search.
is markedly lower, at around 20%.                                             Addressing these challenges in the context of job and talent
                                                                           search could potentially inform investigations into other complex
   Query Diversity Within Users. We now explore the diversity of           search tasks such as searching for cars or properties in the automo-
queries submitted by individual users. For all the job seekers and         tive and real estate domains. As in the employment domain, such
hirers with more than one query in the samples, we computed the            search tasks are part of a decision making process that involves
number of distinct queries they had issued. Figure 3 shows the             high costs (e.g., buying a house). Therefore, the users are more
distribution of unique queries per user for job and talent search.         likely to invest in the search process.
   The box-plots show that hirers submit a higher number of dif-
ferent queries than job seekers. In fact, job seekers tend to repeat
the same queries, whereas in talent search 50% of hirers submit            4   CONCLUSION
more than 10 unique queries. Intuitively, the large variety of roles       Job and talent search have become increasingly offered as effective
that recruiters and employees from HR departments have to hire             online services. However, little work has been done to understand
influences the more varied queries that they use. A job seeker, on         users’ search behavior in these verticals. Our initial exploration
the other hand, generally assume a small number of roles over one’s        suggests that the assumptions we have with regard to user models,
working life. This in turn dictates the range of words that are used       ranking factors and success metrics in web search may not hold
for job search. On the web search front, one may expect a higher           true for job and talent search. Ongoing and further work – which
variability of queries submitted by users – the same user may have         will include deeper analyses of substantially larger click and query
several informational, navigational or transactional needs in a same       logs from one of the most popular online employment marketplaces
day. Moreover, it is known that users struggle to remember web             – will shed some light on the problem of modeling users’ behavior
search queries even after a relatively short amount of time [12].          and satisfaction for job and talent search.
Understanding User Behavior in Job and Talent Search:
An Initial Investigation                                                                                             SIGIR eCom 2017, August 2017, Tokyo, Japan


ACKNOWLEDGMENTS                                                                            [7] Peter Kuhn and Hani Mansour. 2014. Is Internet job search still ineffective? The
                                                                                               Economic Journal 124, 581 (2014), 1213–1233.
This research was partially supported by Australian Research Coun-                         [8] Maarten Lindeboom, Jan Van Ours, and Gusta Renes. 1994. Matching employers
cil Project LP150100252 and SEEK Ltd.                                                          and workers: An empirical analysis on the effectiveness of search. Oxford
                                                                                               Economic Papers 46, 1 (1994), 45–67.
                                                                                           [9] Daan Odijk, Ryen W. White, Ahmed Hassan Awadallah, and Susan T. Dumais.
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