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The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

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Page 1: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

The Modern Firm in Theory & Practice

Nick Bloom (Stanford Economics and GSB)Paul Milgrom (Stanford Economics)

Lecture 5: Scientific Management and Experiments

Page 2: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

CTrip is still going strong (especially after James studied economics at Stanford)

James leavesfor Stanford

James returns from Stanford

Page 3: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Scientific management is probably the oldest formal management theory

Page 4: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Case Summary?

Page 5: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

What are the key elements of CTrip’s Scientific approach to management?

Page 6: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Why is experimentation useful?

Page 7: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

In what circumstances may judgment based management ever outperform scientific management (if ever)?

Page 8: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

CTrip’s style of scientific management is rare (particularly outside the US)

What makes Scientific management so hard in practice?

Page 9: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Does Working from Home Work?Evidence from a Chinese Experiment

Nick Bloom (Stanford)James Liang (Ctrip & Stanford)

John Roberts (Stanford)Zhichun Jenny Ying (Stanford)

January 2015

Page 10: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Two motivations for the paper: (1) Policy

• 20 million people in US report working from home at least once per week, and this is growing rapidly (Oettinger, 2011)

• As a result of this workplace flexibility is becoming an increasingly relevant policy issue, but with little evidence

Source: Council of Economic Advisors (2010) “Report on work-life balance”, Executive Summary

Page 11: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Two motivations for the paper: (2) Productivity

• Working from home is a modern management practice which appears to be stochastically spreading in the US and Europe

• But firms are unclear on it’s impact (which is why our firm ran this experiment) with a wide spread of adoption rates– e.g. Jet Blue has extensive home working, Delta and

Continental have none, and United is experimenting

• So see this as an example of learning about a new management practice, in the spirit of Griliches (1957)

Page 12: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Uncertainty over WFH’s productivity is clear in the media over Yahoo’s February 2013 decision

Page 13: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Even Cosmo ran a story

Page 14: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

And “Pet News” notes this even impacts animals

Page 15: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

15

I got the opportunity to evaluate Working from Home (WFH) with CTrip in 2010• China’s largest travel-agent:16,000 employees, $6bn NASDAQ • James Liang is the co-founder, first CEO and current

Chairman, and from 2008-2012 a Stanford PhD student.• CTrip thinking about rolling-out WFH to save on office rent, but

worried about employees shirking at home

Shanghai, China

Page 16: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

.02

.03

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.05

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1 2 3 4 5 6 7 8 9 10 Wage decile (lowest to highest)

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rsWFH has a bi-modal distribution, and we are evaluating low-income type employees

Largest occupations:Telesales, IT Support and Childcare

Largest occupations:Managers, Sales and IT

Source: IPUMS (2010), a 1% sample of the 2010 Census (137m labor force, 6m report working from home)

Page 17: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

The experiment

Impact on the firm

Impact on the employees

Productivity, profitability and learning

Page 18: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

The experimental background

• CTrip decided to experiment on airfare & hotel departments in Shanghai. They take calls and make bookings

• Employees work 5-shifts a week in teams of about 15 people plus a manager. Hours are fixed by team in advance

• Asked the 996 employees if they wanted to work from home 4 days a week

• 508 volunteered, of which 255 qualified (own-room, BB and 6+ months experience)

Page 19: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

The experimental randomization

• Ran a lottery and even birthdays within the 255 won (became the WFH treatment) and odd stayed in the office as before (the control group)

• Treatment work 4 shifts a week at home and 1 shift a week (at the same time) in the office, for 9 months.

• Otherwise treatment and control identical: same shift, same equipment, same work-flow, same pay structure etc

Why was the lottery public?

Page 20: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Individuals randomized home (even birthdays)

Working at home

Working at home Working at home

Working at home

Page 21: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Team managers stay in the office and monitor their team - including home members - using a range of data and silent monitoring

Home based employees were still actively managed

Also strong performance incentives – pay is 40% based on performance (call number and call quality)

Page 22: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

WFH volunteers more likely to have kids, be married & commute a long way.

Note: Results from a probit on volunteering to work from home

Page 23: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Figure 1: Compliance was between 80% to 90%0

.2.4

.6.8

1

Experiment began on December 6th 2010

Experiment ends on August 14th 2011

Treatment (♦)

Control (+)

Non-volunteer (●)

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Why did not all even birthdays WFH?

Page 24: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Background on the experiment

Impact on the Firm- Output- Spillovers and quality

Impact on the employees

Productivity, profitability and learning

Page 25: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Despite performance pay and monitoring, my prior was negative, in part because of stories like this

Page 26: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

My prior was also negative, in part from the bad general image of working from home – for example

Page 27: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Estimate the impact in a standard panel setting

Want to estimate the impact of assigning volunteer employees to WFH: the “Intention To Treat” (ITT) impact

Outcomei,t = fi + wt + β treatmenti×experimentt + εi,t

where fi + wt are a full set of individual and week fixed-effects, and the errors (εi,t) are clustered by individual.

Page 28: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

In fact working from home led to 13% more calls (0.13=exp(0.122)), 3.5% from more calls taken per minute and 9.5% from more minutes on the phone

Note: All regressions include a full set of individual and week fixed effects, with standard errors clustered by individual. Treatment=even birthday. Hours worked from log-in data.

Page 29: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Experiment yielded three learnings for the firm:(1) Working-from-home works (on average)

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Before the experiment During the experiment

Control

Treatment

Why would an experimenthelp in particular here?

Page 30: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Experiment yielded three learnings for the firm:(2) Better & worse workers both improve when WFH

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Before experiment During experiment

Page 31: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Experiment yielded three learnings for the firm:(3) Selection: Worker choice increases WFH impact

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experimentCompany

roll-outBefore theexperiment

Note: Data from January 4th 2010 until June 1st 2012. Phone calls in z-scores (normalized so the pre-experiment values are mean zero and standard deviation 1) shown as the difference between home and office workers.

Page 32: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Background on the experiment

Impact on the Firm- Output- Spillovers and quality

Impact on the employees

Productivity, profitability and learning

Page 33: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Maybe we are misinterpreting negative spillovers on control group as a treatment impact?

Compared treatment groups to:

- Eligible employees in Nan Tong (the second call center)

- Non-volunteer employees in Shanghai

In both cases treatment (WFH) employees still outperformed

Shanghai Nan Tong

Page 34: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Find no peer spillovers effects comparing to Nan Tong and non-volunteer eligible workers

All regressions include a full set of individual and week fixed effects, with standard errors clustered by individual. Treatment=even birthday. Performance is the z-score measure

Page 35: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

No evidence for any change in quality either

Page 36: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Background on the experiment

Impact on the Firm

Impact on the employees- Promotion- Satisfaction- Attrition

Productivity, profitability and learning

What is the impact you predict?

Page 37: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Significant negative impact on promotions once you control for performance (but no net impact)

Note: Probit of promotion between Dec 6th, 2010 and Sep 30th, 2012, with robust standard errors

Page 38: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Self-reported survey welfare measures are significantly higher for home workers.

Airfare and Hotels group employees were administered regular surveys on their work satisfaction and attitudes by in-house psychologists. The scores are based on the Maslach and Jackson (1981) survey, which is a standard workplace attitude survey.

Page 39: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Attrition is also down, providing harder evidence that (some) employees value working from home

Page 40: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Impact on Individual Performance

Impact on the Firm

Impact on the Employees

Profitability, productivity and learning

Page 41: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Profits: WFH raised profits by $1900 by person per year, leading CTrip to roll out WFH• Reduction in costs per employee WFH per year from :

– Rent: $1,200– Hiring and training: $400– Wages (per call): $300

• So the obvious question is why CTrip (or any other firm) did not do this before?

Page 42: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Why was this not adopted before? Main reason was information - CTrip did not know if working from home would work

They had the idea a few years ago, but worried about shirking at home. Couple of reasons seemed to hold back testing this

1) Organizationally costly to test, and benefit potentially short-lived (process innovations easier to copy)

2) Career concerns of senior managers made them risk-averse. Chairman (James Liang) no managerial career concern and 5% of equity, so he pushed to experiment

Classic example of under-provision of process R&D

Page 43: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Class question:

Was Marissa Meyer right to ban working from home at Yahoo?

Page 44: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

BACK-UP

Page 45: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Impact is evenly spread (not from some outliers)

Phonecalls (normalized mean=0, SD=1) 3 months into experiment

Den

sity

(bi

n=25

)

Page 46: The Modern Firm in Theory & Practice Nick Bloom (Stanford Economics and GSB) Paul Milgrom (Stanford Economics) Lecture 5: Scientific Management and Experiments

Differential attrition could lead to a bias, but biases results down as attrition higher for low performers