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Thursday Complexity Post    
April 2,   2015

Our Capacity for Interconnectivity Has Limits


Are we hard wired to function best in teams of a certain size? Some scientists and business leaders think our cognition and performance suffer when a team gets too big.


In their book Connected: the Surprising Power of Social Networks and How They Shape Our Lives, Nicholas Christakis and James Fowler discuss the work of psychologist Robin Dunbar, who studied the size of different kinds of human groups. The basic Roman army unit was 120 men, and armies throughout many centuries have had 150 men in a unit. Analogous modern armies tend to be about 180 soldiers. Those numbers suggest that despite technological advances, there's an upper limit to the size of a group in which members can function in a coordinated, comprehensive way. Dunbar identified four as the optimum size for a human conversational group, and Connected authors say other researchers studying restaurant patrons, dinner parties and beach goers found people tend to gather in conversational clusters of four.


So what's the right size for a group assembled to launch a product or a sales campaign, to do research, or seek innovation? Rich Karlgaard, in a piece in "Forbes" magazine, advises "Think (Really) Small." Karlgaard notes Amazon founder and CEO Jeff Bezos, advocates the "two pizza rule" for team size. A group that needs more than two pizzas is too big, Bezos has asserted. Bezos thinks people communicate more effectively and productively in small groups, and get more done more quickly. In her management blog, Janet Choi describes some of the science behind this idea, and it supports Dunbar's finding that there are limits on the numbers when it comes to effectiveness in groups of people working closely together.


Karlgaard and Choi explain that the issue is how we manage all the connections between and among people, and organizational psychologists have come up with a formula that shows how the complexity of the network expands exponentially with each additional member. If you multiply the number of people in a group by that number minus one, and divide by two, you'll see the number of links or connections. Karlgaard provides a chart:


2 members = 1 connection

3 members = 3 connections

4 members = 6 connections

6 members = 15 connections

16 members = 256 connections

32 members = 1,024 connections


Karlgaard says if a team reaches 1,500 members, and some big company divisions do, the number of interconnections reaches 2.25 million. Our brains can't handle that, and in very large groups, relationships tend to degrade. Choi quotes research suggesting that people in very large teams are more stressed, work more slowly, and are more vulnerable to miscommunication and misinformation.


Researchers and business leaders vary on optimum size, but most advocate keeping working team membership in the single digits. The Two Pizza rule means it's six or seven. Organizational psychologist J. Richard Hackman likes five and he says don't have more than 10. Management expert Bob Sutton says the U.S. Navy Seals consider four people the optimal number for a combat team."



Remember PlexusCalls!

Friday, April 10, 2015

1-2 PM Eastern Time

Savings Groups: A Catalytic Innovation

Guests: Jeffrey Ashe and June Holley


The traditional notion of microcredit is turned on its head when members of small groups begin saving small amounts of money before they borrow.  Jeffrey Ashe, already a pioneer in microfinance, brought the idea of savings groups to Oxfam more than a decade ago, and Savings for Change has scaled up, has potential for continued growth, and been one of its most successful development initiatives. In addition to gaining access to financial services in areas as not served by banking institutions, group members build social capital, confidence and resilience that add to community resources. These guests are experienced with community collaboration for local economic development.   




Jeffrey Ashe is a Fellow at Carsey School of Public Policy, University of New Hampshire, Research Fellow for Global Development and the Environment at Tufts University and Adjunct Associate Professor at Columbia and Brandeis Universities. Through March 2013 Jeff led Saving for Change at Oxfam America, which grew to 650,000 savings group members in Mali, Senegal, Cambodia, El Salvador and Guatemala. Jeff previously founded and led Working Capital, which was for several years, the largest microfinance institution in the USA. While at Acción International he directed the PISCES studies, the first worldwide study of microfinance, and introduced group lending to Acción in 1981. He has consulted to microfinance projects in more than 30 countries and teaches microfinance at Columbia and Brandeis Universities. Through Carsey, Jeff is bringing savings groups to the USA and will launch new saving group research. His recent book, written with Kyla Jagger Neilan, is "In Their Own Hands: How Savings Groups are Revolutionizing Development."


June Holley  has been weaving economic and community networks for more than 25 years. In 1981 she discovered complexity science and became intrigued with the process of transformation. How could communities change in ways that would make them good places for everyone? With others in Appalachian Ohio, she catalyzed cascades of experimentation, observing and documenting the dynamics that enabled many hundreds of people to start and then expand businesses. With these entrepreneurs, she mobilized dozens of area organizations to collaborate, self-organize and create an environment that would help these businesses innovate and work together. After 20 years as executive director of the Appalachian Center for Economic Networks, she stepped down to help communities around the globe form Smart Networks by training and supporting Network Weavers. She helped clients use Smart Network Analyzer social network mapping software. Her recent Smart Networks projects have involved communities, regions, statewide collaborations, healthcare and hospital systems, and national learning and innovation networks. She is a dynamic keynote speaker and has led hundreds of interactive workshops on applying a network approach. She is working to support infrastructures needed so that networking and self-organizing strategies can expand in groups and communities world-wide.  



Healthcare PlexusCall

Wednesday, April 15, 2014, 1-2 pm ET

Topic: Bright Spotting:

Finding and learning from the right patients to improve outcomes

Guest: Cole Zanetti




Many people agree that the US healthcare system needs to change, but how to go about that complex change is not so easy to see. The Triple Aim Initiative of the Institute for Healthcare Improvement states that new designs need to create better care for individuals, better health for populations, and lower per capita costs-simultaneously. Our guest this month is one of the many innovators who have accepted this challenge.

Cole Zanetti will join the call to share some of the research tools and practices, including predictive analytics and Positive Deviance, he is using in his work. Please bring your own experience and your voice to this vital conversation


Dr. Cole Zanetti is a Family Physician and Leadership Preventive Medicine Resident at Dartmouth Hitchcock Medical Center. Dr. Zanetti is a recent recipient of the American College of Physicians, Primary Care Innovation Award for his proposal on the use of positive deviance as a value based approach to patient engagement. Dr. Zanetti has worked with the Positive Deviance Initiative for the past year to identify new applications for positive deviance in healthcare.

He has worked with the Dartmouth Center for Health Care Delivery Science  on innovative mobile health initiatives in Haiti, was selected by the Robert Wood Johnson Foundation as a Thought Leader for their symposium on Health and Health Care in 2032, and was selected for a National Library of Medicine scholarship for a biomedical informatics-training course. He served as a guest lecturer for the Complex Care Innovation Lab at the Center for Health Care Strategies.  Dr. Zanetti completed his family medicine residency at NH Dartmouth Family Medicine at Concord Hospital where he was awarded the Resident Teacher Award. He is currently an MPH candidate at the Dartmouth Institute for Health Policy and Clinical Practice.


He received his Osteopathic Medical Degree from the Texas College of Osteopathic Medicine where he was the recipient of numerous honors and awards some of which include: the Student Doctor of the Year Award, the Student Health Activist of the Year Award from the American Public Health Association, National Paul Ambrose Political Leadership Scholar Award and the Future Leaders in Preventive Medicine Award. He has also served as the National Chair of Community and Environmental Health for the American Medical Student Association and has worked in Washington DC as a health policy intern for the American Association of Colleges of Osteopathic Medicine. He holds a BA in Psychology from the University at Buffalo.




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