Tensor Fusion Network for Multimodal Sentiment Analysis

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Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing, pages 1103–1114 Copenhagen, Denmark, September 7–11, 2017. c 2017 Association for Computational Linguistics Tensor Fusion Network for Multimodal Sentiment Analysis Amir Zadeh , Minghai Chen Language Technologies Institute Carnegie Mellon University {abagherz,minghail}@cs.cmu.edu Soujanya Poria Temasek Laboratories, NTU, Singapore [email protected] Erik Cambria School of Computer Science and Engineering, NTU, Singapore [email protected] Louis-Philippe Morency Language Technologies Institute Carnegie Mellon University [email protected] Abstract Multimodal sentiment analysis is an in- creasingly popular research area, which extends the conventional language-based definition of sentiment analysis to a mul- timodal setup where other relevant modal- ities accompany language. In this paper, we pose the problem of multimodal senti- ment analysis as modeling intra-modality and inter-modality dynamics. We intro- duce a novel model, termed Tensor Fusion Network, which learns both such dynam- ics end-to-end. The proposed approach is tailored for the volatile nature of spoken language in online videos as well as ac- companying gestures and voice. In the ex- periments, our model outperforms state-of- the-art approaches for both multimodal and unimodal sentiment analysis. 1 Introduction Multimodal sentiment analysis (Morency et al., 2011; Zadeh et al., 2016b; Poria et al., 2015) is an increasingly popular area of affective comput- ing research (Poria et al., 2017) that focuses on generalizing text-based sentiment analysis to opin- ionated videos, where three communicative modal- ities are present: language (spoken words), visual (gestures), and acoustic (voice). This generalization is particularly vital to part of the NLP community dealing with opinion min- ing and sentiment analysis (Cambria et al., 2017) since there is a growing trend of sharing opinions in videos instead of text, specially in social media (Facebook, YouTube, etc.). The central challenge in multimodal sentiment analysis is to model the inter-modality dynamics: the interactions between means equal contribution Figure 1: Unimodal, bimodal and trimodal interac- tion in multimodal sentiment analysis. language, visual and acoustic behaviors that change the perception of the expressed sentiment. Figure 1 illustrates these complex inter-modality dynamics. The utterance “This movie is sick” can be ambiguous (either positive or negative) by itself, but if the speaker is also smiling at the same time, then it will be perceived as positive. On the other hand, the same utterance with a frown would be per- ceived negatively. A person speaking loudly “This movie is sick” would still be ambiguous. These examples are illustrating bimodal interactions. Ex- amples of trimodal interactions are shown in Fig- ure 1 when loud voice increases the sentiment to strongly positive. The complexity of inter-modality dynamics is shown in the second trimodal exam- ple where the utterance “This movie is fair” is still weakly positive, given the strong influence of the word “fair”. A second challenge in multimodal sentiment analysis is efficiently exploring intra-modality dy- namics of a specific modality (unimodal interac- tion). Intra-modality dynamics are particularly 1103

Transcript of Tensor Fusion Network for Multimodal Sentiment Analysis

Page 1: Tensor Fusion Network for Multimodal Sentiment Analysis

Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing, pages 1103–1114Copenhagen, Denmark, September 7–11, 2017. c©2017 Association for Computational Linguistics

Tensor Fusion Network for Multimodal Sentiment AnalysisAmir Zadeh†, Minghai Chen†Language Technologies Institute

Carnegie Mellon University{abagherz,minghail}@cs.cmu.edu

Soujanya PoriaTemasek Laboratories,

NTU, [email protected]

Erik CambriaSchool of Computer Science and

Engineering, NTU, [email protected]

Louis-Philippe MorencyLanguage Technologies Institute

Carnegie Mellon [email protected]

Abstract

Multimodal sentiment analysis is an in-creasingly popular research area, whichextends the conventional language-baseddefinition of sentiment analysis to a mul-timodal setup where other relevant modal-ities accompany language. In this paper,we pose the problem of multimodal senti-ment analysis as modeling intra-modalityand inter-modality dynamics. We intro-duce a novel model, termed Tensor FusionNetwork, which learns both such dynam-ics end-to-end. The proposed approach istailored for the volatile nature of spokenlanguage in online videos as well as ac-companying gestures and voice. In the ex-periments, our model outperforms state-of-the-art approaches for both multimodal andunimodal sentiment analysis.

1 Introduction

Multimodal sentiment analysis (Morency et al.,2011; Zadeh et al., 2016b; Poria et al., 2015) isan increasingly popular area of affective comput-ing research (Poria et al., 2017) that focuses ongeneralizing text-based sentiment analysis to opin-ionated videos, where three communicative modal-ities are present: language (spoken words), visual(gestures), and acoustic (voice).

This generalization is particularly vital to partof the NLP community dealing with opinion min-ing and sentiment analysis (Cambria et al., 2017)since there is a growing trend of sharing opinionsin videos instead of text, specially in social media(Facebook, YouTube, etc.). The central challengein multimodal sentiment analysis is to model theinter-modality dynamics: the interactions between

† means equal contribution

Figure 1: Unimodal, bimodal and trimodal interac-tion in multimodal sentiment analysis.

language, visual and acoustic behaviors that changethe perception of the expressed sentiment.

Figure 1 illustrates these complex inter-modalitydynamics. The utterance “This movie is sick” canbe ambiguous (either positive or negative) by itself,but if the speaker is also smiling at the same time,then it will be perceived as positive. On the otherhand, the same utterance with a frown would be per-ceived negatively. A person speaking loudly “Thismovie is sick” would still be ambiguous. Theseexamples are illustrating bimodal interactions. Ex-amples of trimodal interactions are shown in Fig-ure 1 when loud voice increases the sentiment tostrongly positive. The complexity of inter-modalitydynamics is shown in the second trimodal exam-ple where the utterance “This movie is fair” is stillweakly positive, given the strong influence of theword “fair”.

A second challenge in multimodal sentimentanalysis is efficiently exploring intra-modality dy-namics of a specific modality (unimodal interac-tion). Intra-modality dynamics are particularly

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challenging for the language analysis since mul-timodal sentiment analysis is performed on spo-ken language. A spoken opinion such as “I thinkit was alright . . . Hmmm . . . let me think . . . yeah. . . no . . . ok yeah” almost never happens in writ-ten text. This volatile nature of spoken opinions,where proper language structure is often ignored,complicates sentiment analysis. Visual and acous-tic modalities also contain their own intra-modalitydynamics which are expressed through both spaceand time.

Previous works in multimodal sentiment analysisdoes not account for both intra-modality and inter-modality dynamics directly, instead they either per-form early fusion (a.k.a., feature-level fusion) orlate fusion (a.k.a., decision-level fusion). Early fu-sion consists in simply concatenating multimodalfeatures mostly at input level (Morency et al., 2011;Perez-Rosas et al., 2013; Poria et al., 2016). Thisfusion approach does not allow the intra-modalitydynamics to be efficiently modeled. This is due tothe fact that inter-modality dynamics can be morecomplex at input level and can dominate the learn-ing process or result in overfitting. Late fusion,instead, consists in training unimodal classifiers in-dependently and performing decision voting (Wanget al., 2016; Zadeh et al., 2016a). This prevents themodel from learning inter-modality dynamics inan efficient way by assuming that simple weightedaveraging is a proper fusion approach.

In this paper, we introduce a new model, termedTensor Fusion Network (TFN), which learns boththe intra-modality and inter-modality dynamicsend-to-end. Inter-modality dynamics are modeledwith a new multimodal fusion approach, namedTensor Fusion, which explicitly aggregates uni-modal, bimodal and trimodal interactions. Intra-modality dynamics are modeled through threeModality Embedding Subnetworks, for language,visual and acoustic modalities, respectively.

In our extensive set of experiments, we show (a)that TFN outperforms previous state-of-the-art ap-proaches for multimodal sentiment analysis, (b) thecharacteristics and capabilities of our Tensor Fu-sion approach for multimodal sentiment analysis,and (c) that each of our three Modality Embed-ding Subnetworks (language, visual and acoustic)are also outperforming unimodal state-of-the-artunimodal sentiment analysis approaches.

2 Related Work

Sentiment Analysis is a well-studied research areain NLP (Pang et al., 2008). Various approacheshave been proposed to model sentiment from lan-guage, including methods that focus on opinionatedwords (Hu and Liu, 2004; Taboada et al., 2011; Po-ria et al., 2014b; Cambria et al., 2016), n-grams andlanguage models (Yang and Cardie, 2012), senti-ment compositionality and dependency-based anal-ysis (Socher et al., 2013; Poria et al., 2014a; Agar-wal et al., 2015; Tai et al., 2015), and distributionalrepresentations for sentiment (Iyyer et al., 2015).

Multimodal Sentiment Analysis is an emerg-ing research area that integrates verbal andnonverbal behaviors into the detection of usersentiment. There exist several multimodaldatasets that include sentiment annotations,including the newly-introduced CMU-MOSIdataset (Zadeh et al., 2016b), as well as otherdatasets including ICT-MMMO (Wollmer et al.,2013), YouTube (Morency et al., 2011), andMOUD (Perez-Rosas et al., 2013), however CMU-MOSI is the only English dataset with utterance-level sentiment labels. The newest multimodal sen-timent analysis approaches have used deep neuralnetworks, including convolutional neural networks(CNNs) with multiple-kernel learning (Poria et al.,2015), SAL-CNN (Wang et al., 2016) which learnsgeneralizable features across speakers, and supportvector machines (SVMs) with a multimodal dictio-nary (Zadeh, 2015).

Audio-Visual Emotion Recognition is closelytied to multimodal sentiment analysis (Poria et al.,2017). Both audio and visual features have beenshown to be useful in the recognition of emo-tions (Ghosh et al., 2016a). Using facial expres-sions and audio cues jointly has been the focus ofmany recent studies (Glodek et al., 2011; Valstaret al., 2016; Nojavanasghari et al., 2016).

Multimodal Machine Learning has been a grow-ing trend in machine learning research that isclosely tied to the studies in this paper. Creativeand novel applications of using multiple modali-ties have been among successful recent researchdirections in machine learning (You et al., 2016;Donahue et al., 2015; Antol et al., 2015; Speciaet al., 2016; Tong et al., 2017).

3 CMU-MOSI Dataset

Multimodal Opinion Sentiment Intensity (CMU-MOSI) dataset is an annotated dataset of video

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0%10%20%30%40%50%60%70%80%90%

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Figure 2: Distribution of sentiment across different opinions (left) and opinion sizes (right) in CMU-MOSI.

opinions from YouTube movie reviews (Zadehet al., 2016a). Annotation of sentiment has closelyfollowed the annotation scheme of the StanfordSentiment Treebank (Socher et al., 2013), wheresentiment is annotated on a seven-step Likert scalefrom very negative to very positive. However,whereas the Stanford Sentiment Treebank is seg-mented by sentence, the CMU-MOSI dataset issegmented by opinion utterances to accommodatespoken language where sentence boundaries are notas clear as text. There are 2199 opinion utterancesfor 93 distinct speakers in CMU-MOSI. There arean average 23.2 opinion segments in each video.Each video has an average length of 4.2 seconds.There are a total of 26,295 words in the opinionutterances. These utterance are annotated by fiveMechanical Turk annotators for sentiment. Thefinal agreement between the annotators is high interms of Krippendorf’s alpha α = 0.77. Figure 2shows the distribution of sentiment across differentopinions and different opinion sizes. CMU-MOSIdataset facilitates three prediction tasks, each ofwhich we address in our experiments: 1) BinarySentiment Classification 2) Five-Class SentimentClassification (similar to Stanford Sentiment Tree-bank fine-grained classification with seven scalebeing mapped to five) and 3) Sentiment Regres-sion in range [−3, 3]. For sentiment regression, wereport Mean-Absolute Error (lower is better) andcorrelation (higher is better) between the modelpredictions and regression ground truth.

4 Tensor Fusion Network

Our proposed TFN consists of three major compo-nents: 1) Modality Embedding Subnetworks take asinput unimodal features, and output a rich modalityembedding. 2) Tensor Fusion Layer explicitly mod-els the unimodal, bimodal and trimodal interactionsusing a 3-fold Cartesian product from modality em-beddings. 3) Sentiment Inference Subnetwork is a

network conditioned on the output of the TensorFusion Layer and performs sentiment inference.Depending on the task from Section 3 the networkoutput changes to accommodate binary classifica-tion, 5-class classification or regression. Input tothe TFN is an opinion utterance which includesthree modalities of language, visual and acoustic.The following three subsections describe the TFNsubnetworks and their inputs in detail.

4.1 Modality Embedding Subnetworks

Spoken Language Embedding Subnetwork:Spoken text is different than written text (reviews,tweets) in compositionality and grammar. We re-visit the spoken opinion: “I think it was alright. . . Hmmm . . . let me think . . . yeah . . . no . . . okyeah”. This form of opinion rarely happens inwritten language but variants of it are very com-mon in spoken language. The first part conveys theactual message and the rest is speaker thinking outloud eventually agreeing with the first part. Thekey factor in dealing with this volatile nature ofspoken language is to build models that are capableof operating in presence of unreliable and idiosyn-cratic speech traits by focusing on important partsof speech.

Our proposed approach to deal with challengesof spoken language is to learn a rich representa-tion of spoken words at each word interval anduse it as input to a fully connected deep network(Figure 3). This rich representation for ith wordcontains information from beginning of utterancethrough time, as well as ith word. This way as themodel is discovering the meaning of the utterancethrough time, if it encounters unusable informationin word i+ 1 and arbitrary number of words after,the representation up until i is not diluted or lost.Also, if the model encounters usable informationagain, it can recover by embedding those in the longshort-term memory (LSTM). The time-dependent

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If

you

like

...

see

GloVe h1

h2

h3

hTl

LSTM

LSTM

LSTM

LSTM

... ......

......

zl

128 ReLU 128 ReLU

Figure 3: Spoken Language Embedding Subnet-work (Ul)

encodings are usable by the rest of the pipeline bysimply focusing on relevant parts using the non-linear affine transformation of time-dependent em-beddings which can act as a dimension reducingattention mechanism. To formally define our pro-posed Spoken Language Embedding Subnetwork(Ul), let l = {l1, l2, l3, . . . , lTl

; lt ∈ R300}, whereTl is the number of words in an utterance, be theset of spoken words represented as a sequence of300-dimensional GloVe word vectors (Penningtonet al., 2014).

A LSTM network (Hochreiter and Schmidhuber,1997) with a forget gate (Gers et al., 2000) is usedto learn time-dependent language representationshl = {h1, h2, h3, . . . , hTl

;ht ∈ R128} for wordsaccording to the following LSTM formulation.

ifom

=

sigmoidsigmoidsigmoidtanh

Wld

(XtWle

ht−1

)

ct = f � ct−1 + i�mht = o⊗ tanh(ct)hl = [h1;h2;h3; . . . ;hTl

]

hl is a matrix of language representations formedfrom concatenation of h1, h2, h3, . . . hTl

. hl is thenused as input to a fully-connected network thatgenerates language embedding zl:

zl = Ul(l; Wl) ∈ R128

where Wl is the set of all weights in the Ul net-work (including Wld , Wle ,Wlfc

, and blfc), σ is the

sigmoid function.Visual Embedding Subnetwork: Since opin-

ion videos consist mostly of speakers talking tothe audience through close-up camera, face is themost important source of visual information. Thespeaker’s face is detected for each frame (sampledat 30Hz) and indicators of the seven basic emotions

(anger, contempt, disgust, fear, joy, sadness, andsurprise) and two advanced emotions (frustrationand confusion) (Ekman, 1992) are extracted usingFACET facial expression analysis framework1. Aset of 20 Facial Action Units (Ekman et al., 1980),indicating detailed muscle movements on the face,are also extracted using FACET. Estimates of headposition, head rotation, and 68 facial landmark loca-tions also extracted per frame using OpenFace (Bal-trusaitis et al., 2016; Zadeh et al., 2017).

Let the visual features vj = [v1j , v

2j , v

3j , . . . , v

pj ]

for frame j of utterance video contain the set of pvisual features, with Tv the number of total videoframes in utterance. We perform mean poolingover the frames to obtain the expected visual fea-tures v = [E[v1],E[v2],E[v3], . . . ,E[vl]]. v isthen used as input to the Visual Embedding Sub-network Uv. Since information extracted usingFACET from videos is rich, using a deep neuralnetwork would be sufficient to produce meaningfulembeddings of visual modality. We use a deep neu-ral network with three hidden layers of 32 ReLUunits and weights Wv. Empirically we observedthat making the model deeper or increasing thenumber of neurons in each layer does not lead tobetter visual performance. The subnetwork outputprovides the visual embedding zv:

zv = Uv(v; Wv) ∈ R32

Acoustic Embedding Subnetwork: For eachopinion utterance audio, a set of acoustic fea-tures are extracted using COVAREP acoustic anal-ysis framework (Degottex et al., 2014), including12 MFCCs, pitch tracking and Voiced/UnVoicedsegmenting features (using the additive noise ro-bust Summation of Residual Harmonics (SRH)method (Drugman and Alwan, 2011)), glottalsource parameters (estimated by glottal inversefiltering based on GCI synchronous IAIF (Drug-man et al., 2012; Alku, 1992; Alku et al., 2002,1997; Titze and Sundberg, 1992; Childers and Lee,1991)), peak slope parameters (Degottex et al.,2014), maxima dispersion quotients (MDQ) (Kaneand Gobl, 2013), and estimations of the Rd shapeparameter of the Liljencrants-Fant (LF) glottalmodel (Fujisaki and Ljungqvist, 1986). These ex-tracted features capture different characteristics ofhuman voice and have been shown to be related toemotions (Ghosh et al., 2016b).

1http://goo.gl/1rh1JN

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Unimodal

Language(zl)

Acoustic(z

a)

Visual(z

v)

Early Fusion Unimodal

Language(zl)

Acoustic(z

a)

Visual(z

v)

Tensor Fusion

zl

zv

za za ⊗ zv

zl ⊗ za

zl ⊗ zv

zl ⊗ zv ⊗ za

Figure 4: Left: Commonly used early fusion (multimodal concatenation). Right: Our proposed tensorfusion with three types of subtensors: unimodal, bimodal and trimodal.

For each opinion segment with Ta audio frames(sampled at 100Hz; i.e., 10ms), we extract the setof q acoustic features aj = [a1

j , a2j , a

3j , . . . , a

qj ] for

audio frame j in utterance. We perform meanpooling per utterance on these extracted acous-tic features to obtain the expected acoustic fea-tures a = [E[a1],E[a2],E[a3], . . . ,E[q]]. Here, ais the input to the Audio Embedding SubnetworkUa. Since COVAREP also extracts rich featuresfrom audio, using a deep neural network is suffi-cient to model the acoustic modality. Similar toUv, Ua is a network with 3 layers of 32 ReLU unitswith weights Wa.

Here, we also empirically observed that mak-ing the model deeper or increasing the numberof neurons in each layer does not lead to betterperformance. The subnetwork produces the audioembedding za:

za = Ua(a;Wa) ∈ R32

4.2 Tensor Fusion LayerWhile previous works in multimodal research hasused feature concatenation as an approach for multi-modal fusion, we aim to build a fusion layer in TFNthat disentangles unimodal, bimodal and trimodaldynamics by modeling each of them explicitly. Wecall this layer Tensor Fusion, which is defined asthe following vector field using three-fold Carte-sian product:{

(zl, zv, za) | zl ∈[zl

1

], zv ∈

[zv

1

], za ∈

[za

1

]}

The extra constant dimension with value 1 gener-ates the unimodal and bimodal dynamics. Eachneural coordinate (zl, zv, za) can be seen as a 3-Dpoint in the 3-fold Cartesian space defined by thelanguage, visual, and acoustic embeddings dimen-sions [zl1]T , [zv1]T , and [za1]T .

This definition is mathematically equivalent to adifferentiable outer product between zl, the visualrepresentation zv, and the acoustic representationza.

zm =[zl

1

]⊗[zv

1

]⊗[za

1

]Here⊗ indicates the outer product between vectorsand zm ∈ R129×33×33 is the 3D cube of all pos-sible combination of unimodal embeddings withseven semantically distinct subregions in Figure 4.The first three subregions zl, zv, and za are uni-modal embeddings from Modality Embedding Sub-networks forming unimodal interactions in TensorFusion. Three subregions zl ⊗ zv, zl ⊗ za, andzv ⊗ za capture bimodal interactions in TensorFusion. Finally, zl ⊗ zv ⊗ za captures trimodalinteractions.

Early fusion commonly used in multimodal re-search dealing with language, vision and audio,can be seen as a special case of Tensor Fusion withonly unimodal interactions. Since Tensor Fusionis mathematically formed by an outer product, ithas no learnable parameters and we empiricallyobserved that although the output tensor is highdimensional, chances of overfitting are low.

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We argue that this is due to the fact that the out-put neurons of Tensor Fusion are easy to interpretand semantically very meaningful (i.e., the mani-fold that they lie on is not complex but just highdimensional). Thus, it is easy for the subsequentlayers of the network to decode the meaningfulinformation.

4.3 Sentiment Inference Subnetwork

After Tensor Fusion layer, each opinion utterancecan be represented as a multimodal tensor zm. Weuse a fully connected deep neural network calledSentiment Inference Subnetwork Us with weightsWs conditioned on zm. The architecture of the net-work consists of two layers of 128 ReLU activationunits connected to decision layer. The likelihoodfunction of the Sentiment Inference Subnetworkis defined as follows, where φ is the sentimentprediction:

arg maxφ

p(φ | zm;Ws) = arg maxφ

Us(zm;Ws)

In our experiments, we use three variations of theUs network. The first network is trained for binarysentiment classification, with a single sigmoid out-put neuron using binary cross-entropy loss. Thesecond network is designed for five-class sentimentclassification, and uses a softmax probability func-tion using categorical cross-entropy loss. The thirdnetwork uses a single sigmoid output, using mean-squarred error loss to perform sentiment regression.

5 Experiments

In this paper, we devise three sets of experimentseach addressing a different research question:

Experiment 1: We compare our TFN with previ-ous state-of-the-art approaches in multimodal sen-timent analysis.

Experiment 2: We study the importance of theTFN subtensors and the impact of each individualmodality (see Figure 4). We also compare with thecommonly-used early fusion approach.

Experiment 3: We compare the performanceof our three modality-specific networks (language,visual and acoustic) with state-of-the-art unimodalapproaches.

Section 5.4 describes our experimental method-ology which is kept constant across all experiments.Section 6 will discuss our results in more detailswith a qualitative analysis.

MultimodalBaseline

Binary 5-class Regression

Acc(%) F1 Acc(%) MAE r

Random 50.2 48.7 23.9 1.88 -C-MKL 73.1 75.2 35.3 - -SAL-CNN 73.0 - - - -SVM-MD 71.6 72.3 32.0 1.10 0.53RF 71.4 72.1 31.9 1.11 0.51TFN 77.1 77.9 42.0 0.87 0.70Human 85.7 87.5 53.9 0.71 0.82

∆SOTA ↑ 4.0 ↑ 2.7 ↑ 6.7 ↓ 0.23 ↑ 0.17

Table 1: Comparison with state-of-the-art ap-proaches for multimodal sentiment analysis. TFNoutperforms both neural and non-neural approachesas shown by ∆SOTA.

5.1 E1: Multimodal Sentiment Analysis

In this section, we compare the performance ofTFN model with previously proposed multimodalsentiment analysis models. We compare to thefollowing baselines:

C-MKL (Poria et al., 2015) ConvolutionalMKL-based model is a multimodal sentiment clas-sification model which uses a CNN to extract tex-tual features and uses multiple kernel learning forsentiment analysis. It is current SOTA (state of theart) on CMU-MOSI.

SAL-CNN (Wang et al., 2016) Select-AdditiveLearning is a multimodal sentiment analysis modelthat attempts to prevent identity-dependent infor-mation from being learned in a deep neural network.We retrain the model for 5-fold cross-validation us-ing the code provided by the authors on github.

SVM-MD (Zadeh et al., 2016b) is a SVMmodel trained on multimodal features using earlyfusion. The model used in (Morency et al., 2011)and (Perez-Rosas et al., 2013) also similarly useSVM on multimodal concatenated features. Wealso present the results of Random Forest RF-MDto compare to another non-neural approach.

The results first experiment are reported in Ta-ble 1. TFN outperforms previously proposed neu-ral and non-neural approaches. This difference isspecifically visible in the case of 5-class classifica-tion.

5.2 E2: Tensor Fusion Evaluation

Table 4 shows the results of our ablation study. Thefirst three rows are showing the performance ofeach modality, when no intermodality dynamics aremodeled. From this first experiment, we observethat the language modality is the most predictive.

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Baseline Binary 5-class Regression

Acc(%) F1 Acc(%) MAE r

TFNlanguage 74.8 75.6 38.5 0.99 0.61TFNvisual 66.8 70.4 30.4 1.13 0.48TFNacoustic 65.1 67.3 27.5 1.23 0.36

TFNbimodal 75.2 76.0 39.6 0.92 0.65TFNtrimodal 74.5 75.0 38.9 0.93 0.65TFNnotrimodal 75.3 76.2 39.7 0.919 0.66

TFN 77.1 77.9 42.0 0.87 0.70TFNearly 75.2 76.2 39.0 0.96 0.63

Table 2: Comparison of TFN with its subtensorvariants. All the unimodal, bimodal and trimodalsubtensors are important. TFN also outperformsearly fusion.

As a second set of ablation experiments, we testour TFN approach when only the bimodal subten-sors are used (TFNbimodal) or when only the tri-modal subtensor is used (TFNbimodal). We observethat bimodal subtensors are more informative whenused without other subtensors. The most interest-ing comparison is between our full TFN modeland a variant (TFNnotrimodal) where the trimodalsubtensor is removed (but all the unimodal and bi-modal subtensors are present). We observe a bigimprovement for the full TFN model, confirmingthe importance of the trimodal dynamics and theneed for all components of the full tensor.

We also perform a comparison with the early fu-sion approach (TFNearly) by simply concatenatingall three modality embeddings < zl, za, zv > andpassing it directly as input to Us. This approachwas depicted on the left side of Figure 4. Whenlooking at Table 4 results, we see that our TFNapproach outperforms the early fusion approach2.

5.3 E3: Modality Embedding SubnetworksEvaluation

In this experiment, we compare the performanceof our Modality Embedding Networks with state-of-the-art approaches for language-based, visual-based and acoustic-based sentiment analysis.

5.3.1 Language Sentiment AnalysisWe selected the following state-of-the-art ap-proaches to include variety in their techniques,

2We also performed other comparisons with variants of theearly fusion model TFNearly where we increased the numberof parameters and neurons to replicate the numbers from ourTFN model. In all cases, the performances were similar toTFNearly (and lower than our TFN model). Because of spaceconstraints, we could not include them in this paper.

LanguageBaseline

Binary 5-class Regression

Acc(%) F1 Acc(%) MAE r

RNTN - - - - -(73.7) (73.4) (35.2) (0.99) (0.59)

DAN 73.4 73.8 39.2 - -(68.8) (68.4) (36.7) - -

D-CNN 65.5 66.9 32.0 - -(62.1) (56.4) (32.4) - -

CMKL-L 71.2 72.4 34.5 - -SAL-CNN-L 73.5 - - - -SVM-MD-L 70.6 71.2 33.1 1.18 0.46TFNlanguage 74.8 75.6 38.5 0.98 0.62

∆SOTAlanguage ↑ 1.1 ↑ 1.8 ↓ 0.7 ↓ 0.01 ↑ 0.03

Table 3: Language Sentiment Analysis. Compari-son of with state-of-the-art approaches for languagesentiment analysis. ∆SOTA

language shows improvement.

based on dependency parsing (RNTN), distribu-tional representation of text (DAN), and convolu-tional approaches (DynamicCNN). When possible,we retrain them on the CMU-MOSI dataset (per-formances of the original pre-trained models areshown in parenthesis in Table 3) and compare themto our language only TFNlanguage.

RNTN (Socher et al., 2013)The Recursive Neu-ral Tensor Network is among the most well-knownsentiment analysis methods proposed for both bi-nary and multi-class sentiment analysis that usesdependency structure.

DAN (Iyyer et al., 2015) The Deep Average Net-work approach is a simple but efficient sentimentanalysis model that uses information only fromdistributional representation of the words and notfrom the compositionality of the sentences.

DynamicCNN (Kalchbrenner et al., 2014) Dy-namicCNN is among the state-of-the-art modelsin text-based sentiment analysis which uses a con-volutional architecture adopted for the semanticmodeling of sentences.

CMK-L, SAL-CNN-L and SVM-MD-L aremultimodal models from section using only lan-guage modality 5.1.

Results in Table 3 show that our model usingonly language modality outperforms state-of-the-art approaches for the CMU-MOSI dataset. Whileprevious models are well-studied and suitable mod-els for sentiment analysis in written language, theyunderperform in modeling the sentiment in spokenlanguage. We suspect that this underperformance isdue to: RNTN and similar approaches rely heavilyon dependency structure, which may not be present

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VisualBaseline

Binary 5-class Regression

Acc(%) F1 Acc(%) MAE r

3D-CNN 56.1 58.4 24.9 1.31 0.26CNN-LSTM 60.7 61.2 25.1 1.27 0.30LSTM-FA 62.1 63.7 26.2 1.23 0.33CMKL-V 52.6 58.5 29.3 - -SAL-CNN-V 63.8 - - - -SVM-MD-V 59.2 60.1 25.6 1.24 0.36TFNvisual 69.4 71.4 31.0 1.12 0.50

∆SOTAvisual ↑ 5.6 ↑ 7.7 ↑ 1.7 ↓ 0.11 ↑ 0.14

Table 4: Visual Sentiment Analysis. Comparisonwith state-of-the-art approaches for visual senti-ment analysis and emotion recognition. ∆SOTA

visual

shows the improvement.

in spoken language; DAN and similar sentence em-beddings approaches can easily be diluted by wordsthat may not relate directly to sentiment or mean-ing; D-CNN and similar convolutional approachesrely on spatial proximity of related words, whichmay not always be present in spoken language.

5.3.2 Visual Sentiment AnalysisWe compare the performance of our models usingvisual information (TFNvisual) with the followingwell-known approaches in visual sentiment anal-ysis and emotion recognition (retrained for senti-ment analysis):

3DCNN (Byeon and Kwak, 2014) a network us-ing 3D CNN is trained using the face of the speaker.Face of the speaker is extracted in every 6 framesand resized to 64× 64 and used as the input to theproposed network.

CNN-LSTM (Ebrahimi Kahou et al., 2015) is arecurrent model that at each timestamp performsconvolutions over facial region and uses output toan LSTM. Face processing is similar to 3DCNN.

LSTM-FA similar to both baselines above, infor-mation extracted by FACET is used every 6 framesas input to an LSTM with a memory dimension of100 neurons.

SAL-CNN-V, SVM-MD-V, CMKL-V, RF-Vuse only visual modality in multimodal baselinesfrom Section 5.1.

The results in Table 5 show that Uv is able tooutperform state-of-the-art approaches on visualsentiment analysis.

5.3.3 Acoustic Sentiment AnalysisWe compare the performance of our models usingvisual information (TFNacoustic) with the followingwell-known approaches in audio sentiment analysis

AcousticBaseline

Binary 5-class Regression

Acc(%) F1 Acc(%) MAE r

HL-RNN 63.4 64.2 25.9 1.21 0.34Adieu-Net 59.2 60.6 25.1 1.29 0.31SER-LSTM 55.4 56.1 24.2 1.36 0.23CMKL-A 52.6 58.5 29.1 - -SAL-CNN-A 62.1 - - - -SVM-MD-A 56.3 58.0 24.6 1.29 0.28TFNacoustic 65.1 67.3 27.5 1.23 0.36

∆SOTAacoustic ↑ 1.7 ↑ 3.1 ↓ 1.6 ↑ 0.02 ↑ 0.02

Table 5: Acoustic Sentiment Analysis. Compari-son with state-of-the-art approaches for audio sen-timent analysis and emotion recognition. ∆SOTA

acoustic

shows improvement.

and emotion recognition (retrained for sentimentanalysis):

HL-RNN (Lee and Tashev, 2015) uses anLSTM on high-level audio features. We use thesame features extracted for Ua averaged over timeslices of every 200 intervals.

Adieu-Net (Trigeorgis et al., 2016) is an end-to-end approach for emotion recognition in audiousing directly PCM features.

SER-LSTM (Lim et al., 2016) is a model thatuses recurrent neural networks on top of convolu-tion operations on spectrogram of audio.

SAL-CNN-A, SVM-MD-A, CMKL-A, RF-Ause only acoustic modality in multimodal baselinesfrom Section 5.1.

5.4 MethodologyAll the models in this paper are tested us-ing five-fold cross-validation proposed by CMU-MOSI (Zadeh et al., 2016a). All of our experimentsare performed independent of speaker identity, asno speaker is shared between train and test setsfor generalizability of the model to unseen speak-ers in real-world. The best hyperparameters arechosen using grid search based on model perfor-mance on a validation set (using last 4 videos intrain fold). The TFN model is trained using theAdam optimizer (Kingma and Ba, 2014) with thelearning rate 5e4. Uv and Ua, Us subnetworks areregularized using dropout on all hidden layers withp = 0.15 and L2 norm coefficient 0.01. The train,test and validation folds are exactly the same forall baselines.

6 Qualitative Analysis

We analyze the impact of our proposed TFN mul-timodal fusion approach by comparing it with the

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# Spoken words +acoustic and visual behaviors

TFN-Acoustic

TFN-Visual

TFN-Language

TFN-Early TFN Ground

Truth

1“You can’t even tell funny jokes” +

frowning expression-0.375 -1.760 -0.558 -0.839 -1.661 -1.800

2“I gave it a B” + smile expression +

excited voice1.967 1.245 0.438 0.467 1.215 1.400

3

“But I must say those are some pretty

big shoes to fill so I thought maybe

it has a chance” + headshake

-0.378 -1.034 1.734 1.385 0.608 0.400

4

“The only actor who can really sell

their lines is Erin Eckart” + frown +low-energy voice

-0.970 -0.716 0.175 -0.031 -0.825 -1.000

Table 6: Examples from the CMU-MOSI dataset. The ground truth sentiment labels are between stronglynegative (-3) and strongly positive (+3). For each example, we show the prediction output of the threeunimodal models ( TFNacoustic, TFNvisual and TFNlanguage), the early fusion model TFNearly and ourproposed TFN approach. TFNearly seems to be mostly replicating language modality while our TFNapproach successfully integrate intermodality dynamics to predict the sentiment level.

early fusion approach TFNearly and the three uni-modal models. Table 6 shows examples takenfrom the CMU-MOSI dataset. Each example isdescribed with the spoken words as well as theacoustic and visual behaviors. The sentiment pre-dictions and the ground truth labels range betweenstrongly negative (-3) and strongly positive (+3).

As a first general observation, we observe thatthe early fusion model TFNearly shows a strongpreference for the language modality and seems tobe neglecting the intermodality dynamics. We cansee this trend by comparing it with the languageunimodal model TFNlanguage. In comparison, ourTFN approach seems to capture more complex in-teraction through bimodal and trimodal dynamicsand thus performs better. Specifically, in the firstexample, the utterance is weakly negative wherethe speaker is referring to lack of funny jokes inthe movie. This example contains a bimodal inter-action where the visual modality shows a negativeexpression (frowning) which is correctly capturedby our TFN approach.

In the second example, the spoken words areambiguous since the model has no clue what a B isexcept a token, but the acoustic and visual modal-ities are bringing complementary evidences. OurTFN approach correctly identify this trimodal inter-action and predicts a positive sentiment. The thirdexample is interesting since it shows an interac-tion where language predicts a positive sentiment

but the strong negative visual behaviors bring thefinal prediction of our TFN approach almost to aneutral sentiment. The fourth example shows howthe acoustic modality is also influencing our TFNpredictions.

7 Conclusion

We introduced a new end-to-end fusion methodfor sentiment analysis which explicitly representsunimodal, bimodal, and trimodal interactions be-tween behaviors. Our experiments on the publicly-available CMU-MOSI dataset produced state-of-the-art performance when compared against bothmultimodal approaches. Furthermore, our ap-proach brings state-of-the-art results for language-only, visual-only and acoustic-only multimodal sen-timent analysis on CMU-MOSI.

Acknowledgments

This project was partially supported by Oculus re-search grant. We would like to thank the reviewersfor their valuable feedback.

ReferencesBasant Agarwal, Soujanya Poria, Namita Mittal,

Alexander Gelbukh, and Amir Hussain. 2015.Concept-level sentiment analysis with dependency-based semantic parsing: a novel approach. Cogni-tive Computation 7(4):487–499.

1111

Page 10: Tensor Fusion Network for Multimodal Sentiment Analysis

Paavo Alku. 1992. Glottal wave analysis withpitch synchronous iterative adaptive inverse filtering.Speech communication 11(2-3):109–118.

Paavo Alku, Tom Backstrom, and Erkki Vilkman. 2002.Normalized amplitude quotient for parametrizationof the glottal flow. the Journal of the Acoustical So-ciety of America 112(2):701–710.

Paavo Alku, Helmer Strik, and Erkki Vilkman. 1997.Parabolic spectral parameter—a new method forquantification of the glottal flow. Speech Commu-nication 22(1):67–79.

Stanislaw Antol, Aishwarya Agrawal, Jiasen Lu, Mar-garet Mitchell, Dhruv Batra, C Lawrence Zitnick,and Devi Parikh. 2015. Vqa: Visual question an-swering. In Proceedings of the IEEE InternationalConference on Computer Vision. pages 2425–2433.

Tadas Baltrusaitis, Peter Robinson, and Louis-PhilippeMorency. 2016. Openface: an open source facial be-havior analysis toolkit. In Applications of ComputerVision (WACV), 2016 IEEE Winter Conference on.IEEE, pages 1–10.

Young-Hyen Byeon and Keun-Chang Kwak. 2014. Fa-cial expression recognition using 3d convolutionalneural network. International Journal of AdvancedComputer Science and Applications 5(12).

Erik Cambria, Dipankar Das, Sivaji Bandyopadhyay,and Antonio Feraco. 2017. A Practical Guide to Sen-timent Analysis. Springer, Cham, Switzerland.

Erik Cambria, Soujanya Poria, Rajiv Bajpai, and BjornSchuller. 2016. SenticNet 4: A semantic resourcefor sentiment analysis based on conceptual primi-tives. In COLING. pages 2666–2677.

Donald G Childers and CK Lee. 1991. Vocal qual-ity factors: Analysis, synthesis, and perception.the Journal of the Acoustical Society of America90(5):2394–2410.

Gilles Degottex, John Kane, Thomas Drugman, TuomoRaitio, and Stefan Scherer. 2014. Covarep—a col-laborative voice analysis repository for speech tech-nologies. In Acoustics, Speech and Signal Process-ing (ICASSP), 2014 IEEE International Conferenceon. IEEE, pages 960–964.

Jeffrey Donahue, Lisa Anne Hendricks, Sergio Guadar-rama, Marcus Rohrbach, Subhashini Venugopalan,Kate Saenko, and Trevor Darrell. 2015. Long-termrecurrent convolutional networks for visual recogni-tion and description. In Proceedings of the IEEEconference on computer vision and pattern recogni-tion. pages 2625–2634.

Thomas Drugman and Abeer Alwan. 2011. Joint ro-bust voicing detection and pitch estimation basedon residual harmonics. In Interspeech. pages 1973–1976.

Thomas Drugman, Mark Thomas, Jon Gudnason,Patrick Naylor, and Thierry Dutoit. 2012. Detec-tion of glottal closure instants from speech signals:A quantitative review. IEEE Transactions on Audio,Speech, and Language Processing 20(3):994–1006.

Samira Ebrahimi Kahou, Vincent Michalski, KishoreKonda, Roland Memisevic, and Christopher Pal.2015. Recurrent neural networks for emotion recog-nition in video. In Proceedings of the 2015 ACM onInternational Conference on Multimodal Interaction.ACM, pages 467–474.

Paul Ekman. 1992. An argument for basic emotions.Cognition & emotion 6(3-4):169–200.

Paul Ekman, Wallace V Freisen, and Sonia Ancoli.1980. Facial signs of emotional experience. Journalof personality and social psychology 39(6):1125–1134.

Hiroya Fujisaki and Mats Ljungqvist. 1986. Proposaland evaluation of models for the glottal source wave-form. In Acoustics, Speech, and Signal Process-ing, IEEE International Conference on ICASSP’86..IEEE, volume 11, pages 1605–1608.

Felix A Gers, Jurgen Schmidhuber, and Fred Cummins.2000. Learning to forget: Continual prediction withlstm. Neural computation 12(10):2451–2471.

Sayan Ghosh, Eugene Laksana, Louis-PhilippeMorency, and Stefan Scherer. 2016a. Repre-sentation learning for speech emotion recogni-tion. In Interspeech 2016. pages 3603–3607.https://doi.org/10.21437/Interspeech.2016-692.

Sayan Ghosh, Eugene Laksana, Louis-PhilippeMorency, and Stefan Scherer. 2016b. Represen-tation learning for speech emotion recognition.Interspeech 2016 pages 3603–3607.

Michael Glodek, Stephan Tschechne, Georg Lay-her, Martin Schels, Tobias Brosch, Stefan Scherer,Markus Kachele, Miriam Schmidt, Heiko Neumann,Gunther Palm, et al. 2011. Multiple classifier sys-tems for the classification of audio-visual emotionalstates. In Affective Computing and Intelligent Inter-action, Springer, pages 359–368.

Sepp Hochreiter and Jurgen Schmidhuber. 1997. Longshort-term memory. Neural computation 9(8):1735–1780.

Minqing Hu and Bing Liu. 2004. Mining and summa-rizing customer reviews. In Proceedings of the tenthACM SIGKDD international conference on Knowl-edge discovery and data mining. ACM, pages 168–177.

Mohit Iyyer, Varun Manjunatha, Jordan L Boyd-Graber, and Hal Daume III. 2015. Deep unorderedcomposition rivals syntactic methods for text classi-fication. In ACL (1). pages 1681–1691.

1112

Page 11: Tensor Fusion Network for Multimodal Sentiment Analysis

Nal Kalchbrenner, Edward Grefenstette, and Phil Blun-som. 2014. A convolutional neural network for mod-elling sentences pages 656–666.

John Kane and Christer Gobl. 2013. Wavelet maximadispersion for breathy to tense voice discrimination.IEEE Transactions on Audio, Speech, and LanguageProcessing 21(6):1170–1179.

Diederik Kingma and Jimmy Ba. 2014. Adam: Amethod for stochastic optimization. arXiv preprintarXiv:1412.6980 .

Jinkyu Lee and Ivan Tashev. 2015. High-level fea-ture representation using recurrent neural networkfor speech emotion recognition. In INTERSPEECH.pages 1537–1540.

Wootaek Lim, Daeyoung Jang, and Taejin Lee. 2016.Speech emotion recognition using convolutionaland recurrent neural networks. In Signal and In-formation Processing Association Annual Summitand Conference (APSIPA), 2016 Asia-Pacific. IEEE,pages 1–4.

Louis-Philippe Morency, Rada Mihalcea, and PayalDoshi. 2011. Towards multimodal sentiment anal-ysis: Harvesting opinions from the web. In Proceed-ings of the 13th international conference on multi-modal interfaces. ACM, pages 169–176.

Behnaz Nojavanasghari, Tadas Baltrusaitis, Charles EHughes, and Louis-Philippe Morency. 2016. Emore-act: a multimodal approach and dataset for recogniz-ing emotional responses in children. In Proceedingsof the 18th ACM International Conference on Multi-modal Interaction. ACM, pages 137–144.

Bo Pang, Lillian Lee, et al. 2008. Opinion mining andsentiment analysis. Foundations and Trends R© in In-formation Retrieval 2(1–2):1–135.

Jeffrey Pennington, Richard Socher, and Christopher DManning. 2014. Glove: Global vectors for wordrepresentation. In EMNLP. volume 14, pages 1532–1543.

Veronica Perez-Rosas, Rada Mihalcea, and Louis-Philippe Morency. 2013. Utterance-level multi-modal sentiment analysis. In ACL (1). pages 973–982.

Soujanya Poria, Basant Agarwal, Alexander Gel-bukh, Amir Hussain, and Newton Howard. 2014a.Dependency-based semantic parsing for concept-level text analysis. In International Conference onIntelligent Text Processing and Computational Lin-guistics. Springer, pages 113–127.

Soujanya Poria, Erik Cambria, Rajiv Bajpai, and AmirHussain. 2017. A review of affective computing:From unimodal analysis to multimodal fusion. In-formation Fusion 37:98–125.

Soujanya Poria, Erik Cambria, and Alexander F Gel-bukh. 2015. Deep convolutional neural networktextual features and multiple kernel learning forutterance-level multimodal sentiment analysis. InEMNLP. pages 2539–2544.

Soujanya Poria, Erik Cambria, Gregoire Winterstein,and Guang-Bin Huang. 2014b. Sentic patterns:Dependency-based rules for concept-level sentimentanalysis. Knowledge-Based Systems 69:45–63.

Soujanya Poria, Iti Chaturvedi, Erik Cambria, andAmir Hussain. 2016. Convolutional mkl based mul-timodal emotion recognition and sentiment analysis.In Data Mining (ICDM), 2016 IEEE 16th Interna-tional Conference on. IEEE, pages 439–448.

Richard Socher, Alex Perelygin, Jean Y Wu, JasonChuang, Christopher D Manning, Andrew Y Ng,Christopher Potts, et al. 2013. Recursive deepmodels for semantic compositionality over a senti-ment treebank. In Proceedings of the conference onempirical methods in natural language processing(EMNLP). Citeseer, pages 1631–1642.

Lucia Specia, Stella Frank, Khalil Sima’an, andDesmond Elliott. 2016. A shared task on multi-modal machine translation and crosslingual imagedescription. In Proceedings of the First Conferenceon Machine Translation, Berlin, Germany. Associa-tion for Computational Linguistics.

Maite Taboada, Julian Brooke, Milan Tofiloski, Kim-berly Voll, and Manfred Stede. 2011. Lexicon-basedmethods for sentiment analysis. Computational lin-guistics 37(2):267–307.

Kai Sheng Tai, Richard Socher, and Christopher DManning. 2015. Improved semantic representationsfrom tree-structured long short-term memory net-works pages 1556–1566.

Ingo R Titze and Johan Sundberg. 1992. Vocal in-tensity in speakers and singers. the Journal of theAcoustical Society of America 91(5):2936–2946.

Edmund Tong, Amir Zadeh, and Louis-PhilippeMorency. 2017. Combating human trafficking withdeep multimodal models. In Association for Compu-tational Linguistics.

George Trigeorgis, Fabien Ringeval, Raymond Brueck-ner, Erik Marchi, Mihalis A Nicolaou, BjornSchuller, and Stefanos Zafeiriou. 2016. Adieu fea-tures? end-to-end speech emotion recognition usinga deep convolutional recurrent network. In Acous-tics, Speech and Signal Processing (ICASSP), 2016IEEE International Conference on. IEEE, pages5200–5204.

Michel Valstar, Jonathan Gratch, Bjorn Schuller, Fa-bien Ringeval, Dennis Lalanne, Mercedes Tor-res Torres, Stefan Scherer, Giota Stratou, RoddyCowie, and Maja Pantic. 2016. Avec 2016: De-pression, mood, and emotion recognition workshop

1113

Page 12: Tensor Fusion Network for Multimodal Sentiment Analysis

and challenge. In Proceedings of the 6th Inter-national Workshop on Audio/Visual Emotion Chal-lenge. ACM, pages 3–10.

Haohan Wang, Aaksha Meghawat, Louis-PhilippeMorency, and Eric P Xing. 2016. Select-additivelearning: Improving cross-individual generalizationin multimodal sentiment analysis. arXiv preprintarXiv:1609.05244 .

Martin Wollmer, Felix Weninger, Tobias Knaup, BjornSchuller, Congkai Sun, Kenji Sagae, and Louis-Philippe Morency. 2013. Youtube movie reviews:Sentiment analysis in an audio-visual context. IEEEIntelligent Systems 28(3):46–53.

Bishan Yang and Claire Cardie. 2012. Extracting opin-ion expressions with semi-markov conditional ran-dom fields. In Proceedings of the 2012 Joint Con-ference on Empirical Methods in Natural LanguageProcessing and Computational Natural LanguageLearning. Association for Computational Linguis-tics, pages 1335–1345.

Quanzeng You, Hailin Jin, Zhaowen Wang, Chen Fang,and Jiebo Luo. 2016. Image captioning with seman-tic attention. In Proceedings of the IEEE Conferenceon Computer Vision and Pattern Recognition. pages4651–4659.

Amir Zadeh. 2015. Micro-opinion sentiment intensityanalysis and summarization in online videos. In Pro-ceedings of the 2015 ACM on International Confer-ence on Multimodal Interaction. ACM, pages 587–591.

Amir Zadeh, Tadas Baltrusaitis, and Louis-PhilippeMorency. 2017. Convolutional experts constrainedlocal model for facial landmark detection. InComputer Vision and Pattern Recognition Workshop(CVPRW). IEEE.

Amir Zadeh, Rowan Zellers, Eli Pincus, and Louis-Philippe Morency. 2016a. Mosi: Multimodal cor-pus of sentiment intensity and subjectivity anal-ysis in online opinion videos. arXiv preprintarXiv:1606.06259 .

Amir Zadeh, Rowan Zellers, Eli Pincus, and Louis-Philippe Morency. 2016b. Multimodal sentiment in-tensity analysis in videos: Facial gestures and verbalmessages. IEEE Intelligent Systems 31(6):82–88.

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