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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>ACM SIGIR Workshop on eCommerce, July</journal-title>
      </journal-title-group>
      <issn pub-type="ppub">1613-0073</issn>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>mendations Based on User Intent</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Sanat Sharma</string-name>
          <email>sanatsha@adobe.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jayant Kumar</string-name>
          <email>jaykumar@adobe.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jing Zheng</string-name>
          <email>jinzheng@adobe.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Tracy Holloway King</string-name>
          <email>tking@adobe.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Adobe, Inc.</institution>
          ,
          <addr-line>11501 Domain Drive, Suite 110, Austin, TX 78758</addr-line>
          <country country="US">USA</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Adobe, Inc.</institution>
          ,
          <addr-line>345 Park Ave, San Jose, CA 95110</addr-line>
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <volume>27</volume>
      <issue>2023</issue>
      <abstract>
        <p>Adobe Fonts has a rich library of over 20,000 unique fonts that Adobe users utilize for creating graphics, posters, composites etc. Due to the nature of the large library, knowing what font to select can be a daunting task that requires a lot of experience. For most users in Adobe products, especially casual users of Adobe Express, this often means choosing the default font instead of utilizing the rich and diverse fonts available. In this work, we create an intent-driven system to provide contextual font recommendations to users to aid in their creative journey. Our system takes in multilingual text input and recommends suitable fonts based on the user's intent. Based on user entitlements, the mix of free and paid fonts is adjusted. The feature is currently used by millions of Adobe Express (shown in Fig. 1) users with a CTR ∗Corresponding author.</p>
      </abstract>
      <kwd-group>
        <kwd>mendation systems</kwd>
        <kwd>font recommendations</kwd>
        <kwd>intent understanding</kwd>
        <kwd>text processing</kwd>
        <kwd>neural networks</kwd>
        <kwd>triplet learning</kwd>
        <kwd>recom-</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>CEUR
ceur-ws.org</p>
    </sec>
    <sec id="sec-2">
      <title>1. Introduction: Application</title>
      <p>
        Fonts, including the dificulty of font search and recommendations, have been a well-studied
area in industry and at Adobe in particular. Previous works have tagged fonts with a small
array of tags which can then be used for search. For example, Adobe Fonts ascribes 26 tags
to fonts on its site. Recent works have used the MyFonts dataset to assign tags to fonts and
utilized them for retrieval [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. There are also projects that perform font pairing and retrieval
based on visual appearance of the font [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>However, doing font retrieval based on font tags often misses the semantics governing what
types of contexts the font should be used in. Furthermore, retrieving and recommending fonts
based on the visual style of the fonts already on the canvas often leads to poor results when
there is variety in the content of the page.</p>
      <p>Our work focuses on understanding the intent of the the user’s project using multimodal
input (i.e. text and image context). We then recommend fonts that work well with the project
CEUR
Workshop
Proceedings
intent. This allows us to understand the semantic relationship between the user’s input (e.g.
the text they need to select a font for) and the fonts in our library. Our work comprises:
1. A multimodal Input → Font model that can accurately and reliably recommend a diverse
array of fonts to the user, by extracting their creative intent.
2. A method to recommend “similar” fonts by intent, rather than simple visual appearance.
3. A scalable query architecture for low latency recommendations.</p>
      <p>Since we map the user’s context to intent and then to fonts, we are able to showcase a
diverse set of fonts, including specialized, unique fonts. This intent-based method also allows
us to train our models on a much smaller set of data, which is often a problem in training font
recommendation models. The approach is currently used in production in Adobe Express, with
a CTR of &gt;25% and a downstream project export rate of &gt;50% whenever a recommended font
has been clicked: that is, users who interact with the recommended fonts are likely to finish and
export the project they are working on. Whether the user is using a free, trial, paid, or enterprise
account has an efect on engagement with font selection in general and with subsequent use of
the font recommendations.</p>
    </sec>
    <sec id="sec-3">
      <title>2. Data</title>
      <p>
        In order to mine data for training, we extracted text-font pairs for ∼212,000 texts in Adobe
Express templates. Adobe Express is a platform for people to create flyers, posters, cards,
logos, etc. and hence has templates with a diverse set of fonts. Previous font recommendation
approaches often utilized general text documents, which rarely have much diversity of fonts [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]
[
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>For each text input, we determine the top intents via our intent detection model. The
intent detection model is trained on 1500+ intents, derived from Adobe Express template tags.
These tags range from events such as “Christmas” and “Halloween” to objects and emotional
characteristics such as “balloon”, “happy”, and “encouraging”. This results in triplets of font +
text + intent. This, to our knowledge, is the largest dataset of font-text-intent mappings. Tab. 1
showcases a sample of the training dataset. After further thresholding and preprocessing, we
extract 470,000 rows of text + font + intent triplets that we utilize to train our models.</p>
      <p>Since fonts within a font family are visually similar and have other similar characteristics,
we group similarly used fonts in a font family together based on intent. This grouping helps
capture artistic factors of the fonts and corresponding intents. The final training set consists
of 2043 unique font families to recommend from. Fig. 2 shows examples of fonts and their
associated intents.</p>
      <sec id="sec-3-1">
        <title>Shlop: fun, spooky, halloween, music, art, scary, party</title>
      </sec>
      <sec id="sec-3-2">
        <title>Rig Solid: typography, business, fun, education, fashion,</title>
        <p>music, travel</p>
      </sec>
      <sec id="sec-3-3">
        <title>Sudestada: wedding, floral, marriage, mom, happy</title>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>3. Model</title>
      <sec id="sec-4-1">
        <title>3.1. Intent Detection Model</title>
        <p>3.1.1. Creative Intent Taxonomy
In order to map user creative intent, we semi-automatically extract a creative intent taxonomy
from the Adobe Express content metadata and users’ behavioral data when using and searching
for content. We utilize Adobe Express templates for this taxonomy since the template data
contains rich designer-added tags and represents a diverse set of creative intents. The intents
comprise two main types (example broad and narrower intents in parentheses):
1. Topic of work/task/emotion (e.g. yoga, Halloween, cosmetic, food, book launch, happiness,
birthday, birthday party)
2. Type of creation (e.g. flyer, poster, social media post, card, greeting card, christmas card,
valentine’s day card)</p>
        <p>
          We utilize a pretrained DistilBert [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ] transformer to cluster related topics and then apply
popularity metrics to derive a creative intent taxonomy of over 1500 intents mined from the
Adobe Express dataset. This clustering allows us to collapse terms such as ”mlk jr day”, ”martin
luther jr day” and ”mlk day” into one concept. The most popular term (most frequent occurrence
among all templates) is used to represent the intent.
3.1.2. Multilingual Text-Intent Model
Users often add text to their creation to convey their intent. For example, “Happy Mother’s Day”
is written on Mother’s Day greeting cards, and “We stand in solidarity with black businesses”
for BLM social media posts. It is crucial to infer the intent (topic + type) of a user project
based on the text entered on the canvas or issued as a search. We trained a transformer model
which takes as input a text sample (sentence or phrase or word) and predicts the top, most
probable intents from our curated taxonomy. We extracted over 335,000 texts from Adobe
Express templates and mapped them to the “topics” that were manually tagged by the template
designers. Our final dataset consists of over 1 million text–intent pairs that we utilized to train
our classification model. We fine-tuned a DistilBert [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ] using contrastive learning to learn the
text-to-intent relationships. Our model works for 36+ languages including English, French,
German and Japanese, which is crucial for any production feature at Adobe.
        </p>
      </sec>
      <sec id="sec-4-2">
        <title>3.2. Font Recommendation Model</title>
        <p>
          In order to model intent and fonts in the same embedding space eficiently, we utilized triplet
learning and online triplet mining [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ]. This efectively generates intent-to-font pairings, as
shown in Fig 3. We fine-tuned a pretrained SimCSE model trained on query understanding
[
          <xref ref-type="bibr" rid="ref8">8</xref>
          ] and trained the model with Triplet Margin Loss [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ] with a margin of 2. The loss function
is summarized in equation 1 where:  is the margin; ,  and  denote the anchor, positive
and negative sample respectively;  denotes the neural network. We utilize Adam [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ] as our
        </p>
        <sec id="sec-4-2-1">
          <title>Anchor Text: Be excited for spooky Sunday at my apartment.</title>
        </sec>
        <sec id="sec-4-2-2">
          <title>Intent: spooky</title>
        </sec>
        <sec id="sec-4-2-3">
          <title>Positive: Brim Narrow Combined</title>
          <p>Negative: Bio Sans</p>
        </sec>
        <sec id="sec-4-2-4">
          <title>Anchor Text: We will host a seminar on career development in Welch 102.</title>
        </sec>
        <sec id="sec-4-2-5">
          <title>Intent: informational</title>
          <p>Positive: Journal Negative: Walnut
optimization function with a high learning rate (empirically we found 3 −3 to give the best
results).</p>
          <p>(,  ,  ) = (∥  () −  ( ) ∥
2 − ∥  () −  ( ) ∥
2 +, 0)
(1)</p>
          <p>One challenge was to prevent commonly used fonts from skewing recommendation variation.
For generating the embedding for each font, we found representing a font by a ranked set of its
top 7 intents gave the best results. The ranking is based on the frequency of the intent-font pair
in our dataset. This helped distinguish unique fonts and remove font bias at runtime.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>4. Service Architecture</title>
      <p>The system design of font recommendation has three main components: the font
recommendation service, Search Platform as a Service (SPaaS) and Universal Search Service (USS).</p>
      <p>The USS service defines the input-output schema for clients and acts as the orchestrator
between the font recommendation service and the search platform (SPaaS).</p>
      <p>SPaaS contains the metadata, embeddings and intent information across various Adobe assets
such as backgrounds, images, fonts and Adobe Express templates. SPaaS is responsible for
providing the font recommendation service with input information (context, embeddings, etc.)
present in its Elasticsearch (ES) index as well as extracting font metadata from the ES index for
each recommended font returned from the service.</p>
      <p>At runtime, our clients send user requests (i.e. text input from the Adobe Express editing
canvas) to USS. USS retrieves additional information from SPaaS before sending the full payload
to the font recommendation service. The font recommendation service extracts the intents
from the text input and then uses the weighted set of intents to generate an embedding. This
embedding is used to select font recommendations. When the input language has a restricted
set of compatible fonts (e.g. Japanese), SPaaS provides the recommendation service with the
subset of fonts to recommend from. The full architecture is shown in Figure 4.</p>
    </sec>
    <sec id="sec-6">
      <title>5. Evaluation</title>
      <sec id="sec-6-1">
        <title>5.1. External Manual Evaluation</title>
        <p>We conducted an external evaluation with 75 evaluators. We selected 78 high frequency
templates and displayed them to annotators with one of the texts removed. We then showed
the annotators 5 recommended fonts for the text that had been removed and asked then to rate
each of the fonts as “very good”, “ok” or “not good”. Since font recommendations are highly
subjective, we asked the annotators to fully consider each font’s compatibility with the text.
We found that evaluators considered a text-font pair relevant (very good or ok) 81% of the time
(Table 2).</p>
        <p>We also evaluated a weak baseline of randomly selected fonts and a strong baseline of common
fonts. Both were &gt;10ppt (see fn. 2) worse than the intent-based algorithm. Randomly selected
fonts often showed inappropriate, heavily stylized fonts. Popular fonts showed visually similar
fonts with little diversity or newness: This reduced discoverability of unique fonts (e.g. for
Halloween, where stylized fonts work well, only non-stylized options were shown).</p>
      </sec>
      <sec id="sec-6-2">
        <title>5.2. Internal Manual Evaluation</title>
        <p>We also conducted an internal evaluation with 16 annotators before AB testing the font
recommendations. Similar to the external evaluation, we took 100 texts in multiple languages
(English, French, German, Japanese) from Adobe templates and asked team members to rank
the font recommendations on a scale of 1–5 (1 = very bad, 5 = very good). Our internal results
reflected the external evaluation, with a mean score of 3.67. Since fonts are relatively subjective,
this was considered suficient for AB testing. The score distribution is shown in Table 2. An
example internal evaluation query is shown in Figure 5.</p>
        <sec id="sec-6-2-1">
          <title>Text: pizza pasta burgers</title>
        </sec>
        <sec id="sec-6-2-2">
          <title>Extracted Intents: Food, takeaway, fast food, restaurant, burger</title>
        </sec>
      </sec>
      <sec id="sec-6-3">
        <title>5.3. In-Production Analysis</title>
        <p>Once the external and internal evaluations were completed, the font recommendations were put
in production1 in Adobe Express in the experience shown in Fig. 1. Overall, the recommendations
have a click-through rate (CTR) of &gt;25% and users who select a recommended font have a
downstream project export rate of &gt;50%.
1We cannot report exact numbers for proprietary reasons. Instead we provide lower bounds and relative numbers.</p>
        <p>There are 3 types of user accounts on Adobe Express: Free, trial, and enterprise. Although
the font recommendation algorithm is identical for all users, the percentage of free and paid
fonts depends on their account type. We analyzed the engagement and success of the diferent
types, focusing on users who edited text since font recommendations are only relevant to such
users. Surprisingly, free and enterprise users who edited text had the same rates for using the
font selection module, selecting a recommendation, and exporting a final project. In contrast,
trial users had much higher engagement at each step (font module +15ppt; recommendation
selection +13ppt; export +2ppt).2</p>
        <p>Users who utilize font recommendations have a higher project export (+25ppt) compared
to users who do not. This may be due to the fact that engaged users have higher desire to
complete their projects. This is also consistent with overall project export rates after click on
font recommendation for paid (trial + enterprise + non-enterprise paid) vs. free users. Paid
users had a +10ppt export rate compared to free users after clicking on font recommendations.</p>
        <p>We also saw much higher (3x) engagement on web compared to mobile surfaces. We attribute
this to the fact that the recommendation feature is more prominent on web and that having a
larger screen allows users to browse recommendations more easily.</p>
        <p>Finally we draw some key insights about paid vs. free fonts. For paid users, where there is an
equal split of free and paid fonts, users click on paid fonts slightly more (+2ppt) than free ones.
In contrast, free users are shown a much higher percentage of free fonts and rarely select paid
fonts due to the payment barrier. This suggests that while paid fonts are generally better liked,
they are not enough incentive for most users to convert to paying customers.</p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>6. Conclusion and Next Steps</title>
      <p>This work showcased a novel end-to-end framework for recommending fonts based on
multilingual user input. The recommendation system includes a model to understand user intent and
brings intents and fonts into the same representation space. It includes a low-latency, scalable
architecture to serve the font recommendations. The current approach has high accuracy and
relevance in its recommendations and is in production in Adobe Express.</p>
      <p>Next steps focus on whole document relevance. Firstly, we want to understand the fonts
already in the document so that we can recommend fonts that work in harmony with the
existing artistic design. Secondly, the model described here focuses on individual texts, whereas
global intent is not taken into consideration. Finally, we currently do not support right-to-left
languages like Arabic.</p>
    </sec>
    <sec id="sec-8">
      <title>Acknowledgments</title>
      <p>We thank Andrei Stefan, Ravindra Sadaphule, and Arpita Agrawal for their invaluable help in
productionalizing the font recommendation feature shown in Fig. 1.
2We are unable to publish the exact rates. We report the results as percentage point (ppt) change. For example, a +5
in CTR indicates going from a CTR of X% (e.g. 60%) to a CTR of X+5% (e.g. 65%).</p>
    </sec>
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