Tag: Dennis Zhang



Dennis Zhang has won the 2020 Olin Award for research that creates a human-focused algorithm to improve warehouse workers’ packing time while also reducing material costs.

The Olin Award, which includes business school recognition and a $10,000 prize, is intended to promote scholarly research that has timely, practical applications for complex management problems.

Zhang, assistant professor of operations and manufacturing management, received notice that he had won this year’s award during a short meeting in Dean Mark Taylor’s office on Wednesday afternoon.

His winning research focused on bin packing at the Chinese online retail giant Alibaba to test a human-centric algorithm that, as it turns out, could save Alibaba more than $3 million a year. The paper, “Predicting Human Discretion to Adjust Algorithmic Prescription: A Large-Scale Field Experiment in Warehouse Operations,” is under revision in Management Science.

“Well, that’s a nice surprise,” said Zhang, laughing.

“This was a stunning piece of research,” Taylor told him. “A lot of the judges put ‘number one’ immediately.”

Richard J. Mahoney, former CEO of Monsanto and a Distinguished Executive-in-Residence at Olin, initiated the award, now in its 13th year.

This is Zhang’s second Olin Award. Last year, he and Jake Feldman, assistant professor of operations and manufacturing management, received the award for “Taking Assortment Optimization from Theory to Practice: Evidence from Large Field Experiments on  Alibaba.” They used data from Alibaba to test the benefits of—and recommend a solution for—presenting buyers the optimum variety of products available for purchase with individual online retail stores.

Human-centric algorithm

This year’s winning research focused on workers’ bin packing at Alibaba’s warehouse to test a human-centric algorithm. Conventional bin-packing algorithms prescribe which items to pack in which sequence in which box or bin. All the while, they focus on the best use of a bin’s volume. Here’s the rub: Those algorithms tend to overlook how humans might deviate from the plan.

“Today, the adoption of artificial intelligence (AI) and robotics is accelerating and revolutionizing business operations by augmenting human work,” Zhang and co-authors wrote in their award-winning paper.

“Indeed, rather than striving for autonomous automation, we believe that AI and robotics can improve human work by providing more decision support while always empowering human judgment, oversight and discretion.”

A panel of judges evaluated each of the 19 papers submitted this year for consideration for the Olin Award.

“The topic of the paper and applicability to business are very relevant as e-commerce continues to grow as a business channel in the United States and globally,” one judge wrote about Zhang’s paper. “Understanding how to save time on packing at warehousing is very relevant” and could deliver high savings for big operations like Alibaba and Amazon.

“This is a truly stellar paper,” another judge wrote.  “The issue addressed—how to anticipate human modification of computer algorithms in their work—is a large one across many sectors of the economy.  The randomized, controlled nature of the study makes the conclusions that much stronger. Well done.”

Zhang will be recognized at a luncheon on April 1, where he will have the opportunity to present his research.

Zhang’s co-authors are Jiankun Sun of Imperial College Business School, Haoyuan Hu of the Alibaba Group and Jan A. Van Mieghem of Northwestern University.




As companies trim their hierarchies and form teams of employees to manage themselves, WashU Olin researchers are sounding warning bells. 

Inequity “is likely to be a significant problem”—especially for women, who made one-fourth less than their male counterparts in a new study of self-managed teams.

Lamar Pierce

Women “consistently receive bargaining outcomes below their productivity level, while men are consistently overcompensated,” Olin’s Lamar Pierce and Dennis J. Zhang, with Laura Wang of the University of Illinois, write in “Peer Bargaining and Productivity in Teams: Gender and the Inequitable Division of Pay.” The paper is forthcoming at Manufacturing & Service Operations Management. 

Zappos, Google, Facebook and others have adopted them. The teams are meant to boost productivity, offer flexibility, attract young people and foster creativity. Ideally, they allocate tasks based on employees’ strengths and then assign rewards—equitably—based on their contributions.

But how well do the teams actually work?

Dennis Zhang
Dennis J. Zhang

“Inherently, they aren’t as awesome as people think,” said Pierce, professor of organization and strategy and associate dean of the Olin-Brookings Partnership. (Zhang, professor of operations and manufacturing management, was in Beijing and unavailable for an interview.)

Finding: Women were paid 24% less than men

For 50 months, Pierce, Zhang and Wang studied productivity and bargaining traits in a service operation setting: a chain of 32 large beauty salons with 932 workers in China. About half (54%) of the workers were men. 

They found that the men consistently extracted “advantageous bargaining values from their female coworkers, despite having no observable productivity advantage.”

In fact, women in the sample earned at least 24% less than their equally productive male counterparts. 

That gender pay gap is larger than the pay gaps found in places with hierarchical management structures. A 2005 study found a gap of 10% in Asia and larger inequities in the United States and Europe.

The new evidence on self-managed teams has implications for US organizations.

“You see these dynamics playing out in Silicon Valley all the time. You see them playing out in academia,” Pierce said. 

“Social interactions between men and women have consistencies across culture, across economic class, across age,” he said. “Show me the culture where women don’t tend to get worse negotiation or bargaining outcomes.”

‘Stuck with a bunch of overpaid men’

A combination of higher “prosociality” and lower bargaining power in women most likely explains the 24% wage disparity, the researchers report. Prosocial behavior includes feeling concern for others and acting to benefit them. 

When the workers divided their own team-based compensation, women were severely underpaid for their productivity. Consider this: Women were the top salespeople in the beauty salons, and those women took home only the median wage.

“This is really bad because they’re going to leave, and when they leave then (the company is) going to be stuck with a bunch of overpaid men,” Pierce said.

The researchers compiled data from three sources between April 2009 and May 2013: Point-of-sale from each salon, which included every service and card-for-service transaction; the internal human resource system that included the commission paid to each worker for each transaction; and detailed demographic information of each worker in those transactions.

They found that gender “strongly predicts” under- or overcompensation relative to productivity. Men made up a disproportionate number of highly paid yet unproductive workers. Women overrepresented “star employees” with poor bargaining outcomes.

The researchers used a previously proven algorithm to confirm gender as the strongest predictor of bargaining outcomes.

Out of sight, out of mind

Pierce emphasized that self-managed teams can work well—with clear guidelines in place. The study highlights how important it is to monitor and enforce pay equity in self-managed teams. After all, those teams assign tasks, responsibilities and rewards for teammates.

“Because this design decision effectively puts inequity ‘out of sight for the manager,’ it may also put this inequity ‘out of mind,’” the researchers write. But that doesn’t abdicate a manager’s responsibility to stem bias and discrimination. One solution is to set up formal rules for the assignments of tasks and rewards, the findings suggest. 

“Do you have safeguards in place to ensure that the person who gets all the credit, who gets the rewards, who gets the best task is not simply the one who bargains the best or bargains the most aggressively?” Pierce asked. 

The research findings also imply that firms could cut costs by replacing overpaid workers. And the findings show that good workers who are underpaid lose motivation—and often leave.

“Managers must anticipate and mitigate this gender-based inequity,” the researchers write. That’s because it is an operational performance issue. And “because of the myriad of productivity, retention and ethical implications that can result from peer-based bargaining.”