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Two faculty members from the University of Tennessee, Knoxville’s Haslam College of Business recently published a research brief with The Conversation on their study about how positive emotion affects selling products during live videos.

Business majors and future salespeople are typically taught to provide service with a smile. Service providers such as bank tellers and waiters are encouraged to smile in order to get good customer outcomes.

And even in the data, salespeople were smiling for almost a quarter of the time. Their research challenges this notion and replaces it with a new maxim: sell with a straight face.

The big idea

In new research published in the Journal of Marketing, Michel Ballings, assistant professor of business analytics; Neeraj Bharadwaj, professor of marketing; and Prasad Naik, a marketing professor at the University of California, Davis, found smiling or exhibiting other positive emotional displays while selling a product over live video—known as livestreaming—makes people less likely to buy it.

Michel Ballings
Michel Ballings

Livestreaming through channels such as Amazon Live and QVC is an increasingly popular way to sell goods online. In segments that usually last somewhere between five and 10 minutes, someone pitches a product. Viewers can then readily buy it by clicking on a link.

The team analyzed 99,451 sales pitches on a livestream retailing platform and matched them with actual sales transactions. In terms of duration, that is the equivalent of over two million 30-second television advertisements.

To determine the emotional expression of the salesperson, they used two deep-learning models: a face detection model and an emotion classification model. The face detection model discovers the presence or absence of a face in a frame of a video stream. The emotions classifier then determines the probability that a face is exhibiting any of the six basic human emotions: happiness, sadness, surprise, anger, fear, or disgust. For example, smiling signals a high probability of happiness, while a scowling expression usually points toward anger.

Neeraj Bharadwaj

The researchers wanted to see the impact of emotions expressed at different times in the sales pitch so they computed probabilities for each emotion for all 62 million image frames in our dataset. Then they combined these probabilities with other possible variables that might drive sales, such as price and product characteristics, to isolate the effect of emotion.

The results showed that, perhaps unsurprisingly, when salespeople convey more negative emotions—such as anger and disgust—the volume of sales went down. But also showed that a similar thing happened when the sales pitch involved high levels of positive emotional displays, such as happiness or surprise.

A likely explanation, based on prior research, is that smiling can be off-putting because it lacks authenticity and can reduce trust in the seller. A seller’s happiness may be taken as a sign that the seller is gaining in the negotiation at the customer’s expense.

The researchers found that the negative effects on sales are the strongest when people express emotion in the middle rather than at the beginning or the end of sales pitches. A potential reason for this finding is that viewers might expect more emotion at the beginning of the pitch, when a salesperson is introducing a product, and at the end, when closing the sale. The middle is typically when the salesperson offers more detail about the product, and it’s likely viewers are turned off by emotion at this point in the pitch.

UT is a member of The Conversation—an independent source for news articles and informed analysis written by the academic community and edited by journalists for the general public. Through our partnership, we seek to provide a better understanding of the important work of our faculty.

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