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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Hybrid AI System Delivering Highly Targeted News to Business Professionals</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Anupriya Ankolekar</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>David Brunner</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>ModuleQ, Inc.</institution>
          ,
          <addr-line>19925 Stevens Creek Blvd. Suite 100, Cupertino, CA 95014</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Business professionals need timely, relevant news, but struggle to keep up with the large volume of articles published daily. We present MQ, a hybrid AI news recommender system that uses an explicit model of professionals' commercial relationships to deliver highly targeted news recommendations via a simple chatbot UI. Results from a commercial deployment demonstrate that MQ successfully identifies users' commercial relationships, makes useful recommendations, and drives high and sustained user engagement. We show that domain-specific, knowledge-aware refinements to user modeling and recommendation generation can improve performance.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Hybrid AI</kwd>
        <kwd>Knowledge-aware News Recommenders</kwd>
        <kwd>Data Fusion</kwd>
        <kwd>User Work Modeling</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Timely, relevant business news is essential for professionals who develop and manage
commercial relationships between organizations. These business-to-business (B2B) professionals include
sales executives, account managers, and many senior personnel in financial and professional
services firms. News provides crucial context for decision-making and may reveal opportunities
for new or expanded commercial engagements. For example, when businesses are acquired
or divested, this may influence the prospects of their vendors. However, keeping up with the
immense volume, complexity and interdependence of relevant news and information under
time pressure is a key trigger for information overload in professionals [
        <xref ref-type="bibr" rid="ref1 ref2">1, 2</xref>
        ].
      </p>
      <p>
        Recommender systems [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] are designed to help people find valuable items in vast content.
However, main-stream news recommenders (e.g., Apple News, Google News) have failed to
reduce news overload for consumers [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] and business professionals. These news recommenders
are not targeted enough to deliver valuable recommendations for the highly specific,
fastchanging needs of B2B professionals. A recent survey [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] found that only 32% of C-level
executives felt that information delivered to decision makers in their organization is relevant and
timely. Knowledge about B2B professionals’ work and the corporate domain where they operate
can help identify useful recommendations for an under-served, but important population.
      </p>
      <p>We present an approach to generate highly targeted news recommendations for B2B
professionals by combining data generated by users in the course of their work, domain knowledge,
and knowledge-aware recommendation algorithms. Our approach is embodied in the ModuleQ1
News Recommender (MQ). MQ applies data fusion techniques to learn explicitly structured
user profiles dynamically from users’ communication data, which provide rich signals about the
importance and currency of users’ commercial relationships. Extensive domain knowledge is
used to identify the business entities involved in these commercial relationships and, together
with domain-optimized NLP, to detect the presence of these entities in news articles. A custom,
multi-stage recommendation engine generates proactive, precise, explainable recommendations.
Results from a commercial deployment in the form of explicit user feedback, user engagement
and a user survey show that MQ is efective in delivering relevant news to B2B professionals.</p>
      <p>In the following, Section 2 describes requirements for news recommenders for B2B
professionals and derives design goals for MQ. Related work is discussed in Section 3, specifically
knowledge-aware recommenders and data fusion for modeling a user’s key commercial
relationships. We present our approach to achieving the design goals (Section 4), in particular
deep, domain-tuned modeling and explicit representation of user work driving proactive
recommendations delivered via a chatbot in a secure isolated deployment. The MQ system and
its components are described in Section 5, with a focus on how the approach manifests in the
system. MQ’s performance, in terms of user feedback and engagement results, is discussed in
Section 6, in particular, the efect of domain modeling on the usefulness of MQ’s
recommendations. We discuss the implications and limitations of our approach in Section 7, concluding
with future work.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Design Goals</title>
      <p>B2B professionals often have strong financial incentives tied to short-term, customer-related
business outcomes. Consequently, they tend to focus intensely on developing customer
relationships, while avoiding activities with delayed or ambiguous payofs such as learning
and configuring new tools. Motivated by these characteristics of B2B professionals and the
shortcomings of existing news recommenders, we focused on the following design goals:
(G1) Precise targeting: Reduce information overload by recommending only important
news that is highly relevant to the user’s current needs.</p>
      <p>(G2) Minimal user burden: Sustain user engagement by minimizing the need for manual
profile configuration and by presenting recommendations within the flow of work, so users
need not context-switch into a separate application or web portal.</p>
      <p>(G3) Near-instant value: Increase adoption by creating a short, compelling initial experience
demonstrating the ability of the system to understand the user’s priorities and deliver valuable
news recommendations within a few minutes.</p>
      <p>(G4) Explainability: Earn user trust trust by explaining the system’s recommendations,
especially when relevance to a user’s relationships is not immediately obvious from an article
1The authors are founders of ModuleQ Inc. and have led the design and development of the MQ system. MQ
has been freely accessible since April 2017 as a chatbot on the Microsoft Teams platform and is also available
commercially.
headline. Also, explainability facilitates analysis to further refine the system and supports the
discovery and application of domain-specific heuristics.</p>
      <p>
        (G5) Security &amp; compliance: MQ processes users’ confidential communication data.
Unauthorized access to this information could result in financial or reputational damage, as well as
legal liability. Therefore, we designed our system to be highly secure and to facilitate compliance
with regulatory regimes such as GDPR [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. Related Work</title>
      <p>
        The vast quantity of news published daily causes significant information overload [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] and people
around the world seek more relevant, personalized news [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. This has motivated long-running
research into personalized news recommenders that identify relevant news and filter out the
vast majority of irrelevant content [
        <xref ref-type="bibr" rid="ref8 ref9">8, 9</xref>
        ]. While recommender systems have been successfully
applied in many domains (e.g. for finding books, movies, music, consumer purchases), news
recommenders face specific challenges stemming from the characteristics of news [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Large
data volume, unstructured format, short shelf life, high item churn, and changing user interests
have been identified as factors that “impede the straightforward application of conventional
recommendation algorithms” to news [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ].
      </p>
      <p>
        Knowledge-aware recommenders have been proposed to address challenges of recommending
news. New articles often describe events that can be characterized in terms of the named entities
involved, e.g., organizations, people, and locations. Knowledge about these entities and their
relationships can increase precision, diversity, and explainability. Iana et al. [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] identify six
types of knowledge-aware recommenders distinguished by how knowledge is applied and
how similarity is measured. Our work extends existing knowledge-aware recommenders by
modeling user data to automatically generate up-to-date user profiles, and by matching on a
combination of entities and topics to drive recommendations.
      </p>
      <p>For resolution of named entities in news articles, we selected Refinitiv Intelligent Tagging 2
(RIT), an NLP engine trained on business news. RIT identifies business entities with high
accuracy and resolves them to known business entities with PermId3 identifiers. It also
identifies topics related to the articles. In addition, Refinitiv maintains knowledge about business
entities including revenue, headcount, industry, ownership, executives, directors, and associated
ifnancial instruments, which MQ uses as domain knowledge about the corporate world.</p>
      <sec id="sec-3-1">
        <title>3.1. Data fusion for Modeling Commercial Relationships</title>
        <p>
          Commercial relationships are a primary driver of B2B professionals’ information needs, so
modeling these relationships may improve recommender performance. However, these relationships
are complex, dynamic, and ambiguous. No single system captures the state of the relationship
as it exists in the mind of the professional, although there are clues in business activity traces
strewn across multiple work systems including email, calendar, and customer relationship
management (CRM) systems. Data fusion is a framework for modeling complex phenomena
2https://www.refinitiv.com/en/products/intelligent-tagging-text-analytics
3https://permid.org/
from their traces distributed across multiple data streams that may be fragmentary, noisy, and
intermittent. The JDL Data Fusion model [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ] has been applied and proven in domains as diverse
as intelligent transportation [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ], disaster mitigation [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ], and industry sensor networks[
          <xref ref-type="bibr" rid="ref15">15</xref>
          ],
and has been revised and extended to many problem domains [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ].
        </p>
        <p>
          There is little prior research applying data fusion to model user work, but other modeling
approaches have been used in productivity support tools [
          <xref ref-type="bibr" rid="ref17">17</xref>
          ]. IBM’s activity-centric computing
efort [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ] introduced user activities as a central concept, inferring them from work data, and
developing semantic models and tools for system support [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ]. Emails have been recognized as
being essential to understanding collaborative work [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ], e.g. through person-based methods
[
          <xref ref-type="bibr" rid="ref21">21</xref>
          ]. Another approach [
          <xref ref-type="bibr" rid="ref22">22</xref>
          ] uses clustering over a broader set of user work data (email, calendar,
contacts) to create an implicit representation of user work.
        </p>
        <p>
          User work traces are naturally represented as heterogeneous information networks (HIN) [
          <xref ref-type="bibr" rid="ref23">23</xref>
          ]:
interconnected information graphs embodying rich structural typing and semantic meaning.
Safavi et al. [
          <xref ref-type="bibr" rid="ref24">24</xref>
          ] used a graph-based representation of user work data to identify their ongoing
activities. MQ similarly represents user work data in a HIN, but applies person-based methods
to identify the user’s important business relationships.
        </p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Approach</title>
      <p>Our approach to achieve design goals (G1)-(G5) consists of the following: deep, domain-tuned
modeling combined with an explicit representation of user interests (G1-G4), proactive alerts via
a chatbot interface (G2) and isolated deployment within the organizational perimeter (G5).</p>
      <p>Deep, domain-tuned modeling of user work based on detailed work data (e.g., emails, calendar
events, and CRM records) captures important aspects of a B2B professional’s work context,
including the professional’s relationships with other people and organizations, inter-dependencies
between these relationships, and changes in relationship structure over time. This enables the
creation of rich user interest profiles, providing more precise targeting of recommendations
(G1), minimal user burden in creating profiles (G2) and near-instant value (G3).</p>
      <p>
        We apply data fusion techniques [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] to generate an explicit representation of the user’s
portfolio of inter-organizational relationships, first identifying relationships through the people
involved, then evaluating the dynamics of each relationship, and eventually the likely impact
on the user’s commercial objectives. This explicit modeling approach enables easier application
of domain-specific heuristics and tuning, and also supports explainability (G4). MQ can explain
recommendations in terms of identified relationships, which are more intuitively comprehensible
for the user and allow the user to detect inconsistencies and make manual adjustments. Machine
learning and NLP methods are used throughout the system, but the focus is always on generating
explicit representations that can be reasoned about.
      </p>
      <p>To reduce user burden (G2), MQ uses proactive alerts that surface information at appropriate
times, without any action by the user. Twice daily updates in the morning and afternoon group
together relevant updates. Pre-meeting alerts surface news about specific business relationships
ahead of related meetings. Real-time alerts are used for particularly important and relevant
news. Since alerts have the potential to be disruptive and add to the user’s information overload,
precise targeting (G1) is crucial.</p>
      <p>Work Data
Email, calendar, CRM, etc.</p>
      <p>Domain Knowledge
Business entities &amp; relationships</p>
      <p>NLP as a Service
Refinitiv Intel igent Tagging</p>
      <p>Content</p>
      <p>Business News
200+ publishers</p>
      <p>Profile Service (PS)
Generates user profiles
Tagging Service (TS)
NLP-based metadata tagging</p>
      <p>Content Service (CS)
Content acquisition &amp; retrieval
RecommendationFlow
Knowledge Service (KS)
Continuously learns &amp; updates</p>
      <p>Recommendation Service (RS)
Proactive, personalized updates</p>
      <p>Bot
UI in Microsoft Teams</p>
      <p>Feedback</p>
      <p>To minimize the efort required to access recommendations (G2), MQ provides a chatbot
interface instead of a standalone application or a web portal. Chatbots interact with users
through interactive chat messages, within online workspaces such as Slack and Microsoft
Teams that have become widely adopted by professionals. Via the APIs ofered by online
workspaces, chatbots can deliver alerts within a familiar, cross-platform environment that users
access frequently to converse with colleagues throughout their workday. Chatbots support
interactive features such as hyperlinks and buttons, simplifying collection of user feedback.
Although chatbots are often associated with conversational user interfaces, our system is
designed primarily to deliver proactive alerts and does not support conversational interaction.</p>
      <p>Finally, for security and compliance (G5), we designed the system for isolated deployment
within a cloud computing environment controlled by the users’ employer. This approach did
not materially impact the conceptual operation of the system, but it significantly increased
the complexity and cost of implementation, deployment, monitoring, and maintenance. It also
limits the volume of training data we are able to gather and thus the usage of data-intensive
recommendation methods.</p>
    </sec>
    <sec id="sec-5">
      <title>5. ModuleQ News Recommender</title>
      <p>Figure 1 depicts the conceptual architecture of the ModuleQ News Recommender (MQ) and its
six key subsystems. The Bot component includes the chatbot and associated UI in Microsoft
Teams. The Bot delivers recommendations, suggests newly identified interests, and collects
user behavior data. The Recommendation Service (RS) selects content to recommend to each
user. The Knowledge Service (KS) maintains the system’s knowledge about business entities.
The remaining three subsystems are primarily concerned with processing inputs to the system:
the Profile Service (PS) generates user profiles from work data such as emails, calendar meetings,
and CRM records; the Content Service (CS) ingests and supports retrieval of news articles; and
the Tagging Service (TS) generates metadata for news articles.</p>
      <p>The MQ subsystems were implemented in C# and deployed on Microsoft Azure using
Kubernetes. The Bot uses the Microsoft Teams Bot Framework to expose the UI within Microsoft
(a) News recommendation.</p>
      <p>(b) Interest identified by the Profile Service.
Teams. For security (G5), processes for developing and operating MQ are certified under the
ISO 27001 information security standard. Sensitive user information is encrypted and stays
inside the security and governance perimeter of the user’s organization.
5.1. Bot and UI
MQ interacts with users via chat messages in Microsoft Teams. Figure 2a shows a news
recommendation message displaying the publisher, the article title hyperlinked to the original
article, a set of “Related” tags indicating the most significant metadata tags matched with the
user’s profile, and buttons to provide feedback ( Useful or Not Useful) or to share the article with
colleagues. User feedback in the form of clicked hyperlinks and feedback buttons is collected
for use in learning.</p>
      <p>The Bot also prompts users to provide feedback about the accuracy of commercial relationships
identified by PS, as shown in Figure 2b. This feedback is used to refine user profiles, and to
analyze the performance of the profile generation. To minimize user burden (G2), the Bot only
prompts each user about a small subset of the relationships identified by PS. The full list is made
available to the user in a Profile UI, accessible from the chat via a tab in Teams. Revealing the
full profile, including unconfirmed interests, supports explainability (G4) and allows users to
add or remove interests manually and adjust the recommendations they receive.</p>
      <sec id="sec-5-1">
        <title>5.2. Profile Service</title>
        <p>The Profile Service (PS) detects inter-organizational relationships in the user’s work data,
synthesizing a structured explicit user profile that is used to determine relevant content for
the user. Many organizations appear in user data, so PS needs to evaluate which organizations
are likely to be of greatest commercial significance to a user at any given time. The profile is
updated every hour to ensure an up-to-date profile as the user’s relationships evolve (G1). This
minimizes user burden (G2) in configuring and maintaining their profiles. PS integrates data
from an extensible list of work data sources, currently email, calendar, and CRM records.</p>
        <p>PS periodically ingests each user’s email messages and calendar meetings. Domain-driven
heuristics exclude messages and meetings that are unlikely to be related to significant or current
business activity, for instance, emails sent through consumer email providers that are typically
not used professionally. PS also ingests recent activities and updates to account, opportunity,
and contact records from the user’s CRM system. All ingested data is processed to extract
metadata such as email addresses, organizational domains, and timestamps. Email addresses and
activity objects are annotated to indicate whether they are external to the user’s organization.</p>
        <p>Extracted email domains are mapped to the organizational entities that the domains represent
with the help of the Knowledge Service (KS). Despite a relatively comprehensive knowledge
base of entities, many domains are not resolvable. This is often an indicator that the company
is new or too small to be a significant and news-worthy business entity. Nevertheless, we keep
track of such domains as they may be important to the user and require inclusion in their profile
(G4). This also allows for more accurate estimation of the importance of the relationship, should
these domains become associated with more news-worthy entities in the future.</p>
        <p>After this preprocessing, PS uses clustering to detect B2B relationships (object assessment in
the JDL Data Fusion model) and estimate their salience to the user (situation assessment).</p>
        <sec id="sec-5-1-1">
          <title>5.2.1. Detecting Relationships with Clustering</title>
          <p>Meaningful clusters of business activity are identified in two steps. First, graph-based clustering
is used to identify significant activity hot-spots in the user’s activity data. A heterogeneous
information network (HIN) representing the user’s activity data is constructed, where the nodes
represent external people (email addresses) or organizations. Edges are created when two people
appear together in an activity. A graph-based clustering algorithm then identifies the clusters as
connected components in the graph. These clusters typically represent a business relationship
with a single external entity; however, due to the complexity of B2B relationships, clusters with
multiple organizations are also common.</p>
          <p>During the second step, email domains are used to associate clusters with organizations and
edges within clusters are weighted by the volume of interaction they represent. The clusters are
then refined and pruned by applying domain-specific heuristics. For example, multi-organization
clusters may be split if the communication patterns suggest that the cluster really is composed
of multiple business relationships. Clusters are pruned if they do not appear to represent a
meaningful commercial relationship, e.g. if the communication is only one-way. Accurate
knowledge mapping domains to organizations is critical, because many-to-one mappings from
domains to organizations are common, and so failure to identify multiple domains as belonging
to the same organization can lead to spurious clusters.</p>
        </sec>
        <sec id="sec-5-1-2">
          <title>5.2.2. Estimating Relationship Salience</title>
          <p>For each cluster, we use a set of features to estimate a ‘salience’ score, i.e. the importance of
the corresponding relationship to the user at a given moment in time. For B2B professionals,
meetings tend to be particularly significant in predicting the importance of clusters and are hence
captured in several hand-engineered features. The features were developed through detailed
examination of our own collaboration data and refined through interviews with professionals in
customer-facing roles. Additional features used to predict cluster salience include the number
of people involved from each organization, the number of interactions between the people, and
the proximity of those interactions to the present time. Feature weights were determined ofline
using training data, collected by prompting users (Figure 2b) to confirm whether organizations
associated with the user’s highest-salience clusters are important to them in their work.</p>
          <p>This process yields a user profile in the form of an ordered set of organizations and people
that are important to the user. The user can view the profile created automatically for them and
view a summary of evidence (e.g. number of emails, events, people) for why MQ considered a
particular organization to be an important business relationship. The user profile is also used to
explain MQ’s recommendations in terms of the user’s relationships.</p>
          <p>In addition to tracking organizations and people, the user profile also tracks topics in the form
of keyword phrases such as “Cryptocurrencies” or “Tax accounting software”. The user profile
may be bootstrapped with default topics tuned to the target population for recommendations
that are immediately useful (G3). These are added in consultation with the target organization
and verified with the user. User topic interests are also learnt automatically based on user
feedback on recommendations, and can be entered manually by the user. The universe of topics
is learnt from Refinitiv Intelligent Tagging, as described in Section 5.4.</p>
        </sec>
      </sec>
      <sec id="sec-5-2">
        <title>5.3. Content Service</title>
        <p>The Content Service (CS) is responsible for ingesting content from external sources and for
providing it in clean, annotated form to the rest of the system. In addition to deployment-specific
organizational content sources, CS ingests more than 70,000 articles daily from multiple news
aggregators. News content contains significant noise in the form of click-bait, automatically
generated content, e.g. trading reports, and republished content on multiple sites. CS thus
deduplicates and filters consumer news content, e.g. celebrity news and consumer sales content.
Domain-specific rules and heuristics are used to filter the news and to clean the extracted
unstructured text. The Tagging Service then annotates the cleaned content with tags and
extracts the most reliable and meaningful tags into a content profile. The content along with its
profile is saved in a Mongo database, to be used for recommendation and user display. When
generating recommendations, the Recommendation Service queries CS for content matching a
user profile. CS, in turn, uses Elastic Search for light-weight relevance scoring of articles and
returns the top-ranked recent articles as candidates for recommendation. CS also ensures that
the candidates represent a balanced distribution of the user’s interests.</p>
      </sec>
      <sec id="sec-5-3">
        <title>5.4. Tagging Service</title>
        <p>The Tagging Service (TS) aggregates tags from multiple NLP tagging systems, reconciles them
and resolves them with the Knowledge Service. For NLP tagging and annotation of content, TS
utilizes Refinitiv Intelligent Tagging (RIT) and a custom SpaCy tagging pipeline. RIT provides
named entity recognition and annotates content with a rich set of entity and topic tags tailored
for business content. Each tag receives a relevance score, representing the relevance of that tag
to the article. The organization tags are part of the Refinitiv PermID Linked Data Graph, linking
organizations to people, industries and instruments, and are understood by the Knowledge
Service. Topics tags are gathered from RIT topic tags and other metadata tags, such as products,
technologies, industries and social tags (key noun phrases).</p>
        <p>Our custom SpaCy pipeline has been trained for entity recognition specialized to the business
domain. News articles often mention additional business entities that are only ancillary to the
main story, such as data providers. We developed a custom NLP classifier to annotate mentions
of business entities as data providers, which are subsequently discounted from the entity’s
relevance score.</p>
        <p>At this stage, each article will have multiple, possibly duplicate, tags from diferent sources. TS
clusters these tags, primarily by name, and maps each cluster to an entity within the Knowledge
Service. Each tag is also assigned a relevance score that is computed from the source scores.
Finally, TS classifies articles and annotates them with article meta-tags, e.g., to identify articles
that are likely auto-generated. The list of article tags together with their relevance scores and
the article meta-tags forms a content profile.</p>
      </sec>
      <sec id="sec-5-4">
        <title>5.5. Knowledge Service</title>
        <p>The Knowledge Service (KS) maintains knowledge about all entities and topics known to the
system and provides resolution services to other subsystems. Organizations, people, topics and
geographies, as subclasses of the top-level Thing. Given an Internet domain or a text string, KS
resolves it into an OrganizationThing, a TopicThing or other appropriate subclasses. Internet
domains identified by Profile Service, e.g., are resolved to OrganizationThings in the user’s
profile. The Tagging Service also annotates content with Things, enabling the Recommendation
Service to match profiles to content. KS can be queried for any Thing and returns its model and
the metadata around it.</p>
        <p>KS currently contains knowledge about 862,798 organizations and 2,145,237 topics. This
knowledge is ingested primarily from Refinitiv Content Feeds and the PermID Linked Data
graph, but also from Wikidata and directly from organization web pages. For scale, the KS is
populated by a mostly-automated knowledge ingestion process, with supplementary manual
curation to fix problem data or to handle cases that require human interpretation. It assumes the
existence of multiple external sources that may have incomplete data coverage, old data or other
data issues. The ingestion process ingests information from the above sources and attempts
to reconcile them automatically. If it spots any inconsistencies, these are noted for human
review. As domain mapping is a critical part of our system, we have invested significantly
into manual curation of organizations with domain mapping. In addition, KS keeps track of
the provenance of all knowledge to assist in debugging bad data and diagnosing issues. This
also allows for knowledge from any source to be removed if the source is deemed to be of low
quality or becomes unavailable for use.</p>
      </sec>
      <sec id="sec-5-5">
        <title>5.6. Recommendation Service</title>
        <p>Recommendations are selected from either the news of the past day (∼ 70K volume) for daily
updates or the last two weeks (∼ 750K) for pre-meeting briefings. The Recommendation Service
(RS) queries CS for articles best matching the OrganizationThings and TopicThings in a user
profile. RS filters articles that have already been recommended and scores the relevance of
remaining articles in multiple steps.</p>
        <p>First, the relevance score is computed using modified cosine similarity to consider the salience
of a user’s interest and the relevance of the interest to the article. High matches on both
organizations and topics will result in a high relevance score. Next, references to the user’s
contacts are identified in the articles, and if present, boost the article’s relevance score. For B2B
professionals, any reference to a known client contact is an opportunity to reach out to the client
and further the conversation. We reduce noise by only looking for client contacts in articles
about the client. Domain knowledge is then used to identify and boost articles with special
significance to B2B professionals, such as news about mergers, acquisitions, and leadership
changes. The mapping of topics to these significant events is manually curated and maintained
in KS. In future work, we plan to boost articles with high predicted engagement based on early
user feedback. Finally, article relevance scores are adjusted to prefer recent articles and to prefer
articles from authoritative sources.</p>
        <p>Having scored and ranked articles, RS selects a small subset for delivery to the user. The
selection process picks a diverse set of articles from the top of the ranked list, choosing articles
dissimilar to prior recommendations and avoiding too many articles about the same
organizations. During scoring, the top Things (organizations, topics and people) and boosts contributing
to the relevance score are captured for display to the user, supporting explainability (G4).</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>6. Results</title>
      <p>This section presents results and findings for an MQ deployment at a global financial technology
business with over 10,000 employees. Deployment started with an initial pilot group of about
two dozen users in April 2020. Following a successful pilot, the system was rolled out to over
1,000 employees in early 2021. A majority of the users are in customer-facing roles such as sales,
account management, and customer success. Besides the quantitative behavioural data and
explicit feedback gathered via the Bot, we also collected data on user perceptions via a survey.</p>
      <sec id="sec-6-1">
        <title>6.1. Engagement</title>
        <p>
          Sustained user engagement is an essential performance measure, because busy professionals
tend to abandon systems that they do not find useful. Such abandonment shrinks the share of
active users relative to the population of registered users. Table 1 shows active and registered
MQ users over a six month period. Users are considered active during a time period if they
activate the Bot and view one or more messages. 77% of registered users remained active
monthly until the end of the six-month period. This metric is conservative, as a significant
number of users who left the organization are still counted as registered users. The industry
metric DAU/MAU 4 captures how frequently active users use an application. In October 2021,
MQ DAU/MAU was 59%, a very high level by industry standards [
          <xref ref-type="bibr" rid="ref25">25</xref>
          ].
        </p>
      </sec>
      <sec id="sec-6-2">
        <title>6.2. Identifying User Interests</title>
        <p>In addition to engagement, MQ collects user feedback on how accurately PS identifies
organizations that are important to each user. During the initial onboarding process, the Bot prompts
users to confirm up to three organizations that were ranked as most salient by PS. The Bot
continues to prompt users on an ongoing basis to confirm new organizations that appear highly
4Daily Active Users (DAU) to Monthly Active Users (MAU) is the average number of users active each day in
a given month divided by the number of users active on any day in the month. For our calculation, we exclude
weekends when MQ does not deliver recommendations.
salient in user work data. For a recent three month period (8th August–16th November 2021),
users confirmed 74% of the organizations presented during the initial onboarding stage and 68%
of the organizations presented subsequently (Table 2). Users have the option of manually adding
organization or topic interests. Only a small number of users (60) chose to add interests, with a
slight preference for topics. These results indicate that our approach is efective in determining
user interests, in particular organization relationships, from their work data.</p>
      </sec>
      <sec id="sec-6-3">
        <title>6.3. Recommendation Performance</title>
        <p>MQ news recommendations are accompanied by Useful and Not Useful feedback buttons (Figure
2a). Users can click on the headline (Open) to read the article on the publisher website. News
updates are sent twice daily on weekdays, with each update containing up to four articles.</p>
        <p>During the period July 15th–October 14th 2021, MQ delivered about 602,790 news articles
sourced from 900 publishers to 1176 registered users. Of these, there were 2395 Opens (0.4%) from
472 users. Of the 3231 (0.6%) recommendations with usefulness feedback from 236 users, 59%
were marked Useful and 41% Not Useful (Table 3), equating to a useful ratio5 of 0.59. This ratio is
higher (0.67) for top-ranked articles in daily updates, but decreases to 0.54 for the fourth-ranked
articles. The useful ratio is significantly higher for articles matching users’ organization interests
(0.68) versus those matching only topic interests (0.51), providing evidence that leveraging
knowledge about organizations to prioritize recommendations improves performance.</p>
        <p>Figure 3 plots the useful ratio observed for article recommendations above a given relevance
score percentile. There is a strong positive correlation ( = .93,  &lt; 0.001) between the
relevance percentile and the useful ratio of articles scoring above that percentile. This suggests
that the useful ratio could be increased from the 0.6 actually observed up to 0.9 or higher
5ratio of Useful to total feedback. We use this evaluation metric as an indicator of MQ’s performance, although
it likely incorporates some bias as users choose which articles to give feedback on.
by increasing the relevance threshold for recommending news. However, this would reduce
recommendation volume and likely recall, potentially lowering overall value to users. We have
so far opted to keep recommendation volume, but plan to ofer users a choice to receive fewer,
higher-relevance recommendations.</p>
        <p>We also observe higher useful ratios for recommendations matching users’ organization
interests. This is consistent across the entire distribution of relevance scores. For recommendations
without organization matches, only the top 10% (&gt;90 percentile) reached the level of
usefulness achieved by all recommendations with organization matches. These results underline the
substantial impact of using a domain-specific knowledge-driven refinement—here, prioritizing
users’ organization interests—to achieve precise targeting (G1) for a given user population.</p>
      </sec>
      <sec id="sec-6-4">
        <title>6.4. Survey</title>
        <p>The user survey was distributed by email in October 2021 to all registered users, of whom 99
users completed the survey (response rate 8.3%). The survey asked users about their perceptions
of recommendation volume, timeliness, relevance, and business value. A majority of users
responded positively to all of these questions (see Figure 4). Most users agreed that MQ
highlights timely (65%) and relevant (61%) insights about the user’s interests. This suggests that
MQ does not worsen information overload and does deliver relevant news to professional users.
Users were ambivalent about whether MQ helped them drive conversations with their clients, a
(a) The amount of MQ content
delivered is ...</p>
        <p>(b) MQ highlights timely content
that you may not have found
elsewhere
(c) MQ highlights relevant insights
that you may not have found
elsewhere
(d) MQ helps you drive conversations with
customers and colleagues
(e) How much time does MQ save you each week from having</p>
        <p>to do research on news about your interests?
higher bar for usefulness. We also asked users if MQ reduced the amount of time they need to
spend searching for information. A significant minority of users (27%) reported substantial time
savings, but the majority did not, indicating that proactive recommendations may complement
rather than substitute individual research.</p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>7. Discussion</title>
      <p>The results above demonstrate the value of a hybrid AI news recommender in supporting the
work of B2B professionals with proactive, targeted recommendations. User interviews shed
more light on the value of timely news that can be leveraged to further commercial relationships:
“I was about to have a meeting with [company name], one of the largest energy players
in the region ... and received [an MQ card] just before my meeting about latest news on
[company name] and their recent expansion plan which I used as a topic of discussion
with the client who was very pleased [by] this updated and dynamic interaction. It ...
resulted in signing a [dollar amount] deal next day with the client.” (user feedback by
email, June 22, 2021)
“[Through MQ] I saw that [company name] had acquired one of the biggest [consumer
good] manufacturers in Asia ... I had [a] conversation with the head of trading at
[company name] ... from that conversation we’ve now got a massive integration project
going on where we are bringing a load of business from the APAC region for [company
name] onto [vendor product] that we didn’t see previously . . . and that’s just from one
headline” (user interview, October 7, 2021)</p>
      <p>These user stories underline how being aware of corporate developments is important for
B2B professionals, and suggest why MQ, being tuned for their work domain, had significant
impact on their work performance. MQ’s domain-tuning unfortunately makes it less useful as
a news recommender for general-purpose news or for users in other work domains, such as
consumer-facing sales or engineering. In general, we expect that high quality recommendations
for specific professional populations will likely require specialized recommenders infused with
detailed knowledge about the associated professional domain.</p>
      <p>Specialized news recommenders may need domain-specific tuning similar to the methods
we used to tune MQ for B2B professionals, namely: (1) identify and ingest data that capture
particularly important aspects of the professional’s work; (2) interpret the data to build a user
model that explicitly captures salient aspects of the professional domain, likely with the aid of
specialized domain-specific heuristics; (3) annotate content with NLP models trained to identify
entities, topics, and events salient to the domain; (4) develop a knowledge base with extensive
coverage of entities relevant to the domain, and (5) use knowledge of how diferent entity
categories influence professional work activity to adjust recommendations weights accordingly.</p>
      <p>Despite the value of domain knowledge, we faced some pitfalls by assuming it to be relatively
stable. Domain knowledge may at times be incomplete, not correspond to user expectations, or
become out-dated, which can lead to user confusion or low-quality recommendations in actual
use. We encountered user confusion when an organization better known by its pseudonym
(sometimes called a “trade name” or “DBA” for “doing business as”) was displayed by its legal
name in the MQ UI. Another example involved one organization being acquired by another. As
the operations of the two formerly separate organizations became deeply intertwined and user
data was migrated, the organization afiliations and user email addresses become inconstant and
sometimes inconsistent. MQ assumed a single organizational afiliation for each user, resulting
in user profiles that were out of alignment with actual conditions. These problems reflect the
need to validate knowledge with users and to design for changing knowledge.</p>
      <p>Survey results and user interviews also indicated a need for geography-aware
recommendations. Survey respondents who felt that MQ delivered too much content were more likely to
be located in non-US geographies. MQ allows users to add geographic interests, but this
functionality performed poorly because geographies are rarely interests by themselves, functioning
instead to moderate the relevance of organizations and topics. Therefore, we believe that future
work will need to model geographic interests separately and account for their specific nature
when generating recommendations.</p>
      <p>The high, sustained user engagement with MQ suggests that a simple chatbot UI may be an
efective means of integrating AI into the workflow of busy professionals in many fields. An
interesting observation relevant to recommender designers is that common consumer design
patterns may not translate well to professional contexts. We experimented with soliciting user
feedback with the thumbs-up/thumbs-down, Like/Dislike buttons commonly used in social
media, and the Useful/Not Useful buttons described above. We switched to the latter after user
engagement increased significantly. Users appear to find news useful without ‘liking‘ it.</p>
      <p>The results of our deployment indicate that the users are positive about MQ’s
recommendations, but that there is scope for them to be more relevant and to help drive customer
conversations. In particular, user interviews indicated that explicitly modeling salient aspects of
users’ professional roles may help tune recommendations. This could be especially efective for
specialized professionals focused on specific technologies, regulatory regimes, types of financial
instruments or transactions, or categories of risk. Furthermore, we plan to model additional
business-relevant entities and relationships, and experiment with recommendation algorithms
that can utilize these efectively in the recommendation process.</p>
    </sec>
    <sec id="sec-8">
      <title>8. Conclusion</title>
      <p>We presented MQ, a hybrid AI news recommender system for B2B professionals that models
users’ commercial relationships and delivers proactive, highly targeted news recommendations
via a simple chatbot UI. Deployment at a global enterprise shows that MQ is efective at
understanding users’ commercial relationships and making useful recommendations. Incorporating
salient domain entities into modeling of user work and the recommendation process yields
significantly more useful recommendations.</p>
      <p>Our work is one of the first to apply recommendation systems to improve information
overload for B2B professionals, an important but under-served audience. We further identified
news recommendations for specific populations of professionals as a promising area for the
development of hybrid AI systems, combining knowledge about the user’s work and about the
domain to generate highly-targeted recommendations with minimal user efort. Characteristics
of MQ’s knowledge-aware architecture may be adaptable to other domains, namely, applying
data fusion techniques to model explicit, time-varying user profiles from multiple noisy data
streams and incorporating domain-specific heuristics to prioritize recommendations that are
highly salient to the user’s work domain.</p>
    </sec>
    <sec id="sec-9">
      <title>Acknowledgments</title>
      <p>We are grateful to Edward Feigenbaum for his mentoring and encouragement, to our strategic
partner London Stock Exchange Group for their enthusiastic support, and to the ModuleQ
engineering team for developing our research ideas into a commercial-grade enterprise system.</p>
    </sec>
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