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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Preference Mapping for Automated Recommendation of Product Attributes for Designing Marketing Content</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Moumita Sinha</string-name>
          <email>mousinha@adobe.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Rishiraj Saha Roy</string-name>
          <email>rroy@adobe.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="editor">
          <string-name>Preference Mapping, Sentiment Scores, Product Attributes</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Adobe Research Labs</institution>
          ,
          <addr-line>India Bangalore</addr-line>
          ,
          <country country="IN">India -</country>
          <addr-line>560029</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Algorithms</institution>
          ,
          <addr-line>Experimentation, Human factors</addr-line>
        </aff>
      </contrib-group>
      <fpage>64</fpage>
      <lpage>67</lpage>
      <abstract>
        <p>Identification of relevant product attributes is critical to the success of any marketing campaign. This task can be conceptualized as an attribute recommendation problem based on the product's content or features, where the goal of a solution would be to automatically recommend relevant features to the marketer for highlighting in a campaign. In this research, we try to solve this problem by using preference mapping, a powerful technique for associating feature preferences with users. We perform preference mapping with sentiment scores associated with product attributes mined from user reviews on the Web. As a result of this process, we are able to visualize a set of compared products and the appropriateness of the attributes on the same two-dimensional space, enabling us to easily recommend important features to a marketer. Finally, we show that expert recommendations or ratings for product features do not necessarily correlate with preference maps based on user sentiments.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Categories and Subject Descriptors</title>
      <p>Information retrieval [Retrieval tasks and goals]:
Recommender systems</p>
    </sec>
    <sec id="sec-2">
      <title>1. INTRODUCTION</title>
      <p>Motivation. Product manufacturers are always faced
with the dilemma of identifying which attribute(s) of their
products they should highlight in their targeted marketing
campaigns. For example, a digital camera has several
defining aspects like power of zoom, size of display and image size
in megapixels. A release of a new camera model by a
manufacturer like Nikon will usually be followed by a marketing
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Canodp/oyrraigfheet. R2e0q1u4estfpoerrmtihsseionisndfriovmidpuearmlispsaiopnesr@sacbmy.otrgh.e paper’s authors.
CCBoRpyeciSnygs ’p1e4r,mOictttoebderf6o,r20p1r4iv,aStielicaonndVaallceayd,Cemaliifcorpniuar,pUoSsAes.. This volume is
pCuobpylirsighhetd2a01n4dAcCopMy9ri7g8h-1te-4d5b03y-2it2s57e-d7i/t1o4r/s0.7 ...$15.00.</p>
      <p>
        ChtBtpR://edcxS.dyosi.2o0rg1/140,.O11c4t5o/b26e0r064,228.0216409,4S7i8li.con Valley, CA, USA.
campaign to potential customers that will try to highlight
certain aspects or attributes of the model. This attribute
recommendation problem is critical to the success of the
campaign. Focusing on features that do not appeal to users
can result in a loss of large amount of ad spend and potential
losses in product revenue for a manufacturer. In this paper,
we address this challenge by proposing a principled
technique called preference mapping [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], used in a novel way to
automate the process of product attribute recommendation.
      </p>
      <p>
        Related research. Alpert [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] presents one of the
relatively early works emphasizing the importance of identifying
relevant product attributes, and compares the e↵ ectiveness
of direct and indirect questioning techniques. Cropper et
al. [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] finds that a linear hedonic price function performs
as well as a linear logit model in estimating consumer
preferences for product attributes. But their analysis is based
on simulations and does not draw connections between
preferred attributes and campaign design. Zhang and Liu [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]
try to identify product features that are associated with user
sentiment by analyzing the contextual text associated with
the mention of the product feature. While it could be
meaningful to further scrutinize such attributes while designing
product campaigns, the authors do not propose any method
towards that end. Lehdonvirta [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] aims to discover
product attributes that are likely to drive purchase decisions for
virtual goods like online games and engaging activities on
social media. However, the analysis presented by the author
is purely from a sociological perspective and the author does
not provide an algorithm for automating the above process.
Recommendation algorithms similar to collaborative
filtering have been used for designing campaigns, but they rely
heavily on large amounts of existing customer preference
data available with the advertiser [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. On a related note,
they are also known to have limitations such as data
sparsity and model scalability, which leads to poor
recommendations [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. We provide a method for associating products with
their marketable attributes that relate to each other based
on publicly available sources. Such data sources may become
accessible much before the advertiser receives direct
information about customers’ preferences based on product view or
product purchase data. Preference mapping is an approach
to identify customer preferences based on users’ surveys of
product attributes. Individual user di↵ erences are not
averaged, but are directly incorporated into the mapping model
and play vital roles in the preference fitting process [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. As
of date, the technique has only been used for understanding
user preferences for diverse food items like lamb sausages [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ],
lager beer [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] and vanilla ice cream [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. We believe that this
method has a far greater potential and can be readily
extended to unexplored application areas.
      </p>
      <p>Approach. In this research, after specifying our product
and attribute set, we acquire sentiment scores of user reviews
that mention attributes for the products in our set.
Following this, we associate user sentiments with the attributes
mentioned in the reviews (instead of the product as a whole)
and average them over reviewers who have written reviews
concerning the attributes. We perform preference mapping
on this processed dataset involving products, attributes and
average sentiment scores and generate a biplot visualization
that can be used for attribute recommendation. Finally,
we compare our recommendations with expert opinion and
show that there is no perfect correlation with what experts
believe to be good features and what consumers like in a
marketed product.</p>
      <p>Organization. The rest of this paper is organized as
follows. In Sec. 2, we describe our method of applying
preference mapping to this situation. Next, we describe our data
in Sec. 3 followed by experimental results and discussion in
Sec. 4. Finally, we summarize our contribution and provide
directions for future work in Sec. 5.</p>
      <sec id="sec-2-1">
        <title>METHOD</title>
        <p>
          We analyze a set of products p and a set of product
attributes k. Customers who have bought these products
often go to the product or retailer website to provide feedback
about the product in the form of textual reviews. Most
of these reviews generally contain mentions of product
attributes. Further, positive or negative sentiments usually
accompany the above mentions of the attributes. In our
approach, we collect reviews where each sentence talks about
only one attribute. Appropriate anaphora resolution is
performed for review sentences when the attribute name is not
directly mentioned [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ]. Each sentence in each review is then
assigned a sentiment score. Since each sentence mentions
exactly one attribute, the sentiment score associated with
the sentence is assumed to be the score associated with the
attribute. Note that the ee↵ctiveness of our algorithm is
not a↵ected by the scale or range of this sentiment scoring.
Next, the scores are averaged over the reviewers for each
attribute for each product.
        </p>
        <p>A preference mapping is then performed with the
revieweraveraged scores of each of the various attributes for the
different products. We now explain how this is performed. As
the first step, sentiment scores for all the product attributes
are scaled to the same range so that variances are
comparable across attributes of each product. Consider X =
(X1, X2, . . . , Xp)T as the matrix of the reviewer-averaged
scores for the p products (say, di↵erent camera models) and
the k attributes (like battery life, size of display and shutter
delay). Thus each Xi is a vector with its elements as Xij,
which is the reviewer-averaged sentiment score for attribute
j of product i. The principal component (PC)
transformation of the feature vector X is the linear transformation
Y = T (X µ) where µ = E(X) and ⌃ = V ar(X) = 0.
The transformation is such that V ar(Y ) is maximized and
the following holds:
1
2
. . .</p>
        <p>p
where, V ar(Yj) = j, j = 1, 2, . . . , p, E(Yj) = 0 and
Cov(Yj, Yi) = 0 when i 6= j.</p>
        <p>Functions V ar(·), E(·) and Cov(·) refer to the variance,
expectation, and covariance functions, respectively, and the
j’s represent the eigenvalues of the matrix X. These
eigenvalues have the corresponding eigenvectors as 1, 2, . . . , p
(the number of eigenvectors is equal to the rank of the
matrix X). Then the ith PC for each product is the weighted
sum of the scores of the product across the attributes, the
weights being obtained from the ith eigenvector. A biplot
graph can be plotted for PC1 and PC2 with the weighted
scores of each of the products and the eigenvector values for
each attribute. The resultant graph provides an easily
interpretable visualization that shows how products compare
among each other based on customer reviews and the
relative proximity of each attribute to their respective products
with respect to associated positive user sentiment. Based
on this multivariate visualization, marketing contents can
be designed, highlighting favorable attributes for products.
A schematic of the steps a marketer will undergo to utilize
statistical analysis of social reviews to design product
specific marketing campaigns is shown in Figure 1. Relevant
steps have been explained in this section. Specific details
about our dataset and experimental setup will be provided
in the next section.</p>
        <p>We test our approach on a dataset consisting of 1309
reviews related to four digital camera models (Canon G3,
Canon Powershot SD500, Canon S100, and Nikon Coolpix
4300), having a total of 13 distinct attributes. These
attributes (or features) that we analyzed are: flash, zoom,
battery, auto (quality of automatic mode), photo quality,
view (quality of view through the viewfinder), delay (delay
between photos), look, start (startup speed), color, night
(quality of night photos), lens and resolution. The reviews
are pre-processed to identify mentions of camera attributes
within their texts. The 13 attributes are mentioned a total
of 583 times in the product reviews that we collected.</p>
        <p>Expert ratings. It is an interesting exercise to
compare our attribute recommendation system to expert
opinion. To this end, we went through popular digital camera
review sites dcresource1 and imaging-resource2 for
extracting expert ratings on the thirteen attributes for our
1http://www.dcresource.com, Accessed 11 July ’14.
2http://www.imaging-resource.com, Accessed 11 July ’14.</p>
        <p>Canon G3</p>
        <p>Canon PowerShot SD500
Canon S100</p>
        <p>Nikon coolpix 4300
four camera models. Since none of the popular camera
review sites provide direct numeric ratings for attributes, we
mapped expert opinion to a score of 1 or 2 depending upon
the comments provided. For example, comments containing
words like exceptional, excellent and good about an attribute
were mapped to two, and weak and worst were assumed to
be a one rating. The data that we collected has been made
publicly available at http://goo.gl/v8BGj4.</p>
      </sec>
      <sec id="sec-2-2">
        <title>EXPERIMENTS AND RESULTS</title>
        <p>We assign a sentiment score to each sentence in each
review in our dataset with the Alchemy API3 and transfer the
score to the attribute mentioned in the sentence. The higher
the magnitude of the score, the stronger is the strength of
the associated sentiment. Following this, the positive and
negative sentiment scores of all the 52 (= 13 ⇥ 4)
cameraattribute pairs were averaged together over all the reviewers
who mentioned the pair in his/her reviews, the neutral
sentiments contributing zero to the sum. The missing
observations are assumed to be neutral sentiments and hence the
scores in such cases are assumed to be zero. These average
sentiments for each camera over all attributes are shown in
a radial chart in Figure 2. As a specific example, the
battery of the Canon S100 was mentioned in 13 reviews, with
seven, one, and five review(s) showing positive, negative and
neutral scores respectively. While the numbers of positive
and negative mentions seem comparable, the average
positive and negative sentiment scores were found to be 1.3461
and 0.3569 respectively, indicating that the strength of the
negative sentiment was not as strong as the positive
sentiment. In our experiments, the two values were averaged to
obtain 0.8515.</p>
        <p>We now have a matrix with four rows (corresponding
to each camera model) and thirteen columns
(corresponding to each model attribute). The cells of this matrix are
the reviewer-averaged sentiment scores associated with each
camera and attribute pair. A principal component analysis
(PCA) is then performed on this matrix of camera-attribute
pairs. The PC1 and PC2 for this example, cumulatively
explain 85% of the variability in the data. We then produce
the biplot of the weighted scores of the products and the
eigenvectors of each of the attributes, as shown in Figure 3.
2
1
20
PC
−1
−2</p>
        <p>Canon G3
color
lens</p>
        <p>battery
resolfuutniocntion
asutatort
phvoiteow Nikon coolpix 4300look
zoom delay</p>
        <p>flash
−2</p>
        <p>Canon PowerShot SD500
PC01
2
Canon S100</p>
        <p>This graph provides a lot of information for design of
marketing campaigns. First, in the graph, two attributes (in red)
that are pointing towards the same direction, are attributes
that tend to be highly positively correlated. A product that
is in the same direction as an attribute, has a high value
for this attribute. Thus, from the graph, we can conclude
that attributes, which are closer and in the same direction
as a product, are the ones that should be recommended for
highlighting in marketing content for that particular model.
For example, Canon G3 and Canon S100 received high
sentiment scores on attributes like lens and color, while Nikon
Coolpix 4300 and Canon PowerShot SD500 received high
positive sentiments on low shutter delay and zoom quality.
Thus, for example, lens and color should be recommended
for designing marketing content in the campaign for Canon
G3, rather than the zoom.</p>
        <p>Second, this methodology also helps to contrast
competing products simultaneously and provides competitive
intelligence to the marketer. Thus, based on the given set of
consumers’ reviews, one can deduce that Nikon Coolpix 4300
and Canon PowerShot SD500 are similar with respect to the
attributes studied, as compared to Canon G3 and Canon
S100. For example, if Nikon Coolpix 4300 and Canon
Powershot SD500 are competing products, then it is meaninful
to recommend only discriminatory features that add value
to a particular product for its campaign. It is more sensible
to recommend flash for Nikon Coolpix 4300 (more closer to
the model than Canon 500) than the zoom, which is
approximately equidistant from the both the products.</p>
        <p>Analysis of expert opinion. From the data collected on
expert comments (Sec. 3), we find that many of the discussed
attributes are rated as 2, which implies that these attributes
are “excellent” or “good” (Table 1). We assume that high
expert score is analogous to high positive sentiment.</p>
        <p>Table 2 shows the Kendall-Tau rank correlation
coecients between the preference mapping technique and the
plain average sentiment scores (which is the unweighted sum
of the attributes as opposed to the weighted sum for each
camera). For three cameras we have statistically significant
(at 0.05 level) correlation between the methods and a
moderExpert ratings were not available for all the attributes. So the sum
of the values in a row may not add up to one
ate correlation for Nikon Coolpix 4300. This shows that our
method has high correlation with the intuitive
understanding of the importance of the attributes and helps in further
refinement. We could not observe any direct relation
between the predictions based on the preference mapping and
the attributes highly rated by experts.</p>
      </sec>
      <sec id="sec-2-3">
        <title>CONCLUSIONS AND FUTURE WORK</title>
        <p>
          The preference mapping technique, as described by us in
this research, recommends potentially “valuable” attributes
of products to marketers for highlighting in a marketing
campaign. Our method provides the marketer the ability
to design marketing content that can potentially increase
response rates. We have used sentiment scores for product
attributes, extracted from review texts to identify product
features to be highlighted in campaigns. By focusing on
attributes that are known to have received positive sentiments
of customers, the risk in the campaign is minimized.
Moreover, the comparison with the experts’ comments suggests
that sometimes, what customers value more about a
product may be di↵erent from attributes that experts consider
of high quality. So, designing marketing content taking into
account what a large section of consumers show positive
sentiments towards may help in engaging more e↵ectively with
a larger section of the consumers. The sentiment score in
our research is a continuous variable and PCA has been used
to identify appropriate attributes that have high scores. If
some or all the scores are categorical in nature, multi-factor
analysis [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ] is preferable over PCA. The proposed
technology does not require large amounts of customer preference
data to be available internally with the advertiser (for
example, customers who have viewed the same product or
customers who have bought the same product), from their own
sales and browsing patterns. Rather, we use reviews that
directly reflect customer preferences. The reviews can be
collected from any external source with consumers’ opinion.
The other major strength of our approach is that it is more
likely to be positively viewed by the future customer. Such
an approach enables having an informed conversation with
0.385
0.615
0.385
0.615
0.564
0.615
0.641
0.294
Kendall-Tau
p-Value
        </p>
        <p>Poor
the potential customer and is likely to improve customer
satisfaction.</p>
        <p>As future work, we would like to cluster products using
attribute sentiment scores as features and observe the
correlation of the clustering output to the representation produced
by our preference mapping technique. Also, the quality of
the reviews can be improved by choosing relevant users by
mapping them to specific customer segments. This can lead
to better insights on the data and finer levels of control in
the design of marketing content.</p>
      </sec>
      <sec id="sec-2-4">
        <title>Acknowledgements</title>
        <p>We thank Ritwik Sinha from Adobe Research Labs India for
valuable inputs at various stages of this work.
6.</p>
      </sec>
    </sec>
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