How to Interpret Polls–Do Not Forget the Margin of Error and the Sample Size

By Matt ColeComments Off

With the U.S. presidential election on November 6, we are presented with an ever increasing onslaught of political polls and their results. To make a proper interpretation of a poll’s results, three additional variables should be specified in addition to the proportion results: the poll’s margin of error, the desired level of confidence, and the sample size. In this brief essay, I will review the math behind the margin of error in polls to help you with interpretation of polls.

Background Information
The purpose of a poll is to estimate the opinion or behavior of a population from a sample. We work with a sample since contacting the entire population is too time consuming, often too expensive, and can be physically impossible. Several methods of sampling are used, and simple random sampling, systematic sampling, stratified sampling, and cluster sampling are the most widely used methods.

After the sample is selected from the population, a statistic computed from sample information estimates a population parameter.  The statistic computed from the sample that estimates the population parameter is called a point estimate. As an example, the sample mean, , is the point estimate of the population parameter, μ, the population mean. For polls, the sample proportion, ρ, is the point estimate of the population parameter, π, the population proportion.

How Close is the Point Estimate to the Population Parameter?
We now come to the essence of this essay–the confidence interval estimate (CI). A confidence interval estimate is a range of values constructed from sample data so that the population parameter is likely to occur within that range at a specified probability. The specified probability is called the level of confidence, and in most cases of poll results, the level of confidence is set at .95 (i.e., a pollster has a 95% confidence that the true measurement lies within the margin of error). Putting all of this together gives us the following equation:  CI = point estimate ± margin of error

Accordingly, the CI is determined from the margin of error. You’ve seen the margin of error in some poll results, e.g., “The poll has a margin of error plus-minus 3.1 percentage points for the sample.” If the poll determined that ρ = .5, then the CI would be 50% ± 3.1% = 46.9-53.1, i.e., a pollster has a 95% confidence that the true poll results are 46.9% to 53.1%

I will now show how the margin of error is used to determine a poll’s CI and sample size.

How Is the CI Determined in a Poll?
To determine the CI in a poll, we will use the following formula to compute the margin of error: z * standard error. Mathematically, this formula is expressed as:

In this formula, z defines the level of confidence. In polls, the 95% level of confidence gives us a z score of 1.96. Also in polls, we determine the standard error as the maximum standard error by setting the proportion at 50% (ρ = .5).

We plug in these numbers to determine the margin of error at the 95% level of confidence:


Polls that we see in the media use the 95% level of confidence in determining the margin of error. However, statisticians also determine the margin of error using the 90% and 99% levels of confidence, although the 95% l.98evel of confidence is the most common. The margin of error for the 90% confidence level is calculated using a z score of 1.65:

For the 99% confidence level, the margin of error is calculated using a z score of 2.58:

How Is the Sample Size of a Poll Determined?
I noted above that the purpose of a poll is to estimate the opinion of a population from a sample. As researchers, we are interested in the generality of the data in terms of the number of subjects in the population to which the results apply. If a poll has a margin of error of 3.1%, we can use the formula for the margin of error to estimate the size of the sample:

A recent poll from NBC News/Wall Street Journal reported the following poll results:

Obama is ahead of Romney by five points, 49 percent to 44 percent. The full poll was conducted Oct. 17-20 among 1,000 registered voters. The poll has a margin of error plus-minus 3.1 percentage points for the sample of registered voters.

According to the formula above, we can see how the margin of error was calculated from the sample size of n = 1,000 registered voters.

Putting it All Together
A new TIME Poll has Obama holding a 49% to 44% lead over Romney in Ohio. The poll’s margin of error is plus or minus three percentage points. How do we interpret the results of this poll?

First, we estimate the sample size: n = (.98/.03)² = 1,067.

Second, we estimate the CI around each point estimate at the 95% level of confidence. Obama: 46-52     Romney: 41-47.

Finally, we decide that according to the results of this particular poll, a sample of 1,067 people in Ohio are equally likely to vote for Obama or Romney 95 times out of 100 (because the CIs overlap).

Conclusion
I wrote this essay to provide some clarity and perspective on election polls by reviewing the statistics behind polls. I emphasized that the result of a poll must be interpreted along with the poll’s margin of error so that the sample size and CI can be determined.

For more information on the science of polls, check out Nate Silver’s book The Signal and the Noise: Why So Many Predictions Fail-But Some Don’t, and Nate Silver’s blog FiveThiryEight

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US nonprofit sector is a job creator

By College of Management2,841 Comments

October 24, 2012
Jerry Lindman, JD

This article in CNN.com (Look to nonprofit sector to create jobs, CNN Oct 19, 2012) makes the case for the resilient job creating ability of the US nonprofit sector over the last decade, even in this slow-growth economy. Though not a surprise to some (including our LTU graduate nonprofit students), many are still unaware of the dramatic growth in the nonprofit sector and the employment opportunities that exist.  Here are some key points the author makes:

  • “the nonprofit sector employs about one in 10 American workers…..the third largest labor force behind retail trade and manufacturing.”
  • “According to a recent study the U.S. nonprofit sector posted a remarkable 10 year record of job growth despite
  • two recessions, achieving an annual growth rate of 2.1% from 2000 to 2010…..for-profit jobs declined by 0.6% per year during the same period.”
  • The same study showed that “even during the recession from 2007 to 2009, nonprofit jobs increased by an average of 1.9% per year. At the same time, businesses averaged jobs losses of 3.7% per year.”
  • “While nonprofits are known for employing social workers, they also need managers, human resource professionals, educators, artists, computer programmers, marketers, accountants…researchers…and many skilled workers.”

This author closes by calling of the next President (and Congress?) to do five things to support nonprofit job growth: (1) maintain tax deductions for donations and on estate tax; (2) incentivize nonprofit education and careers; (3) expand national service via the proposed ‘Serve America Act’ (4) Invest in social entrepreneurship to promote innovation in the nonprofit sector and (5) expand tax incentives for financing of small business to nonprofits.

From my work with nonprofit organizations and their leaders, growth is just one of the major forces causing transformation of how charitable organizations operate. Because of these dynamic times, what is most needed are newly educated and trained nonprofit managers who can blend the unique nonprofit management competencies with new business-influenced strategies that support diversification of their revenue sources to include more earned income. Coincidentally, that is the topic my students are addressing this week in my graduate course in nonprofit management.

Nonprofit Management

DBA Student, Lihua Dishman, Presenting her Research at the Great Lakes Conference on Teaching & Learning

By Anne Kohnke3,436 Comments

Lihua Dishman, a DBA student in Cohort 8, presented the conceptual part of her qualitative inquiry on exemplary online adult learners at 2012 Great Lakes Conference on Teaching & Learning in May at Mt. Pleasant, MI.  This study utilizes the existential phenomenological inquiry method, which focuses on reporting lived experiences that are grounded in existence. Data collection relies on the perceptions of the participants–the 30 university instructors.  The findings of this study thus may reflect the personal biases of these participants.  The concept of an Exemplary Online Adult Learner needs to be further explored and refined.  The effect of key characteristic factors of an Exemplary Online Adult Learner on achieving learning outcomes of individual courses and the entire degree program warrants further research through larger samples.

Lihua Dishman, DBA Student in Cohort 8

The Global Leadership course, one of her first classes in the DBA program, inspired her research interest.  Both the Introduction to Doctoral Research and Qualitative Research courses empowered her with the necessary tools to complete the conceptual part of this exploratory inquiry.  Lihua’s presentation is a powerful testimonial for LTU and COM’s education philosophy of linking theory to practice.

Conference Presentations, Doctoral Student Scholarship

Lunch-Network with Foundation Professionals – LTU – Sept 25

By College of Management3,364 Comments

Jerry Lindman

The LTU Center for Nonprofit Management is pleased to be hosting the annual Lunch With Leaders of the Emerging Practitioners In Philanthropy of Michigan at Lawrence Tech, UTLC Gallery, on Tues. Sept 25, 12:00-2:00pm.  I highly recommend attending this lunch & networking event to anyone who seeking to learn more about Michigan philanthropic and foundation world.   Lunch will be included in your registration fee of $5; register at: http://www.eventbrite.com/event/4172863146

The speakers are Derek Aguirre, Executive Director of Racquet Up Detroit and Doug Stewart, Executive Director Max M. and Marjorie S. Fisher Foundation.

About Lunch With Leaders (LWL): LWL is an annual statewide event is provided by Emerging Practitioners In Philanthropy of Michigan[Jerry Lindman]  (EPIP-Michigan); Email: epipmichigan@gmail.com or visit http://www.epip.org/chapters/michigan

Nonprofit Management

COM Faculty Attend the 2012 AOM Conference in Boston

By Matt Cole1,716 Comments

College of Management faculty Dr. Anne Kohnke, Dr. Jacqueline Stavros, and Dr. Matthew Cole attended the The Academy of Management 2012 Annual Meeting in Boston. The theme of the 2012 program was The Informal Economy:

“The informal economy refers to commercial activities that occur at least partially outside a governing body’s observation, taxation, and regulation. Sociologists Manuel Castell and Alejandro Portes suggest that the “informal economy is…characterized by one central feature: it is unregulated by the institutions of society in a legal and social environment in which similar activities are regulated.” In contrast to the informal economy, the formal economy is comprised of commercial activities that a governing body taxes and monitors for society’s benefit and whose outputs are included in a country’s gross domestic product. For many decades, management scholars have examined research questions that are almost exclusively centered on the organizations and individuals located in the formal economy. That is about to change.”

For students who are not familiar with the AOM, The Academy of Management started in 1936 when Professors Charles L. Jamison of the University of Michigan and William N. Mitchell of the University of Chicago organized a meeting of management educators to discuss and promote the philosophy of management. “The Academy has evolved from an organization of 10 members to an organization of over 17,500 members from over 105 nations. Today, the Academy’s 25 professional divisions and interest groups promote excellence in established management disciplines. Five U.S.-based affiliates, the Eastern, Midwest, Southwest, and Western Academies of Management and the Southern Management Association as well as two international affiliates, the Asia and Iberoamerican Academies of Management, promote the exchange of ideas and provide collaborative opportunities for colleagues sharing a geographic area, language, or cultural identity.”

Graduate management students can join the AOM for $91.00. The annual conference offers excellent opportunities for COM doctoral students to discuss their dissertations and receive critiques from AOM scholars and practitioners, as well as other AOM doctoral students.

In addition to attending informative paper sessions, symposiums, and professional development workshops, Drs. Kohnke, Stavros, and Cole had a great time networking and socializing in Boston.

 

 

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Welcome to Dean Bahman Mirshab!

By Al McCord2,887 Comments

Dean Bahman MirshabPlease join the faculty and staff in welcoming Dean Bahman Mirshab to Lawrence Tech’s College of Management. Dean Mirshab comes to Lawrence Tech from the Cameron School of Business at the University of St. Thomas in Houston, Texas. He was formerly dean of the College of Business at the University of Detroit-Mercy, and received his Ph.D. from Wayne State University.

Dean Mirshab successfully led the University of St. Thomas to AACSB accreditation, and we look forward to his leadership in helping us attain our goal of AACSB accreditation. Lawrence Tech issued a press release on August 7 announcing Dean Mirshab’s appointment.

Interim Associate Dean Stavros and I were proud to lead the College on an interim basis and look forward to working closely with Dean Mirshab in the future.

Sincerely,

 

 

 

Dr. Alan McCord
Associate Provost and Dean of Graduate Studies

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Supreme Court Rules on Affordable Care Act: What does it say & where do we go from here?

By College of Management1,518 Comments

By Jerry Lindman, J.D.

The US Supreme Court issued their ruling today (June 28, 2012) on the constitutionally of the Federal healthcare reform law passed in 2010 (Patient Protection and Affordable Care Act of 2010) and its various parts. What does it say and where do we go from here? I offer short-term and longer term perspectives on next steps on this important matter.

In the short term, a 5-4 majority of justices upheld all key provisions of the Affordable Care Act of 2010 including the individual mandate. Though their ruling and the way they decided it will have implications on future Congressional action, in effect, the US Supreme Court affirmed its constitutionality and sent it back into the realm of our elected public policy makers to implement, execute and improve. For a concise, simple overview of what the US Supreme Court ruling said, see Health-Care Ruling: A Scorecard, from the Wall Street Journal’s Law Blog,  http://blogs.wsj.com/law/2012/06/28/health-care-ruling-a-scorecard . For on-going legal analysis and other developments related to the Supreme Court’s ruling, see Scotus Blog – http://www.scotusblog.com/category/special-features/health-care

What I find far more informative and inspiring is the longer term look “up-stream” that leading stakeholders and experts committed to universal healthcare in the US are taking. This “up-stream” examination looks well beyond the immediate legal, policy and political discourse regarding the Affordable Care Act of 2010, to identify and develop a growing consensus around next steps in public policies and practices that will remake what we now think of as our US healthcare system.  Their vision and action plan involves much more than is being discussed today by our elected policymakers and the media. As they see it, health is not just something that comes from the doctor’s office, it also is an outcome of addressing many community and neighborhood conditions that create an environment for healthy living.

The June 2012 Symposium sponsored by the Robert Woods Johnson Foundation (www.rwjf.org ) did a good job of capturing consensus from this group of leading stakeholders which include academic, business and government. In the Symposium’s Final Report[1], this diverse group of stakeholders conclude:

  1. “No matter how the Supreme Court rules on the Affordable Care Act, health care in the next 20 years will need leadership that embraces community needs and new roles to care and guide individuals across a more data-driven, accountable U.S. health system. That was a consensus reached by health leaders brought together this week by the Foundation for an intensive two-day symposium in Kansas City to explore the future of health and health care in 2032. Though the high court’s decision looms large, the Justices’ coming ruling was barely acknowledged by the diverse group of more than 50 leaders from across the national health spectrum. The group included clinicians, academics, entrepreneurs and business executives from employers that ranged from Google to IBM.”
  2. They see four “alternative futures” for what healthcare in the US may look like in 2032; 1.) Slow Reform, Better Health, 2) Health If You Can Get It, 3) Big Data, Big Health Gain and 4) The New Ethics of Health. Alternative future #1 they describe as resulting from a “Zone of Conventional Expectation”. Alternative future #2 arises from the “Zone of Growing Desperation”. Alternatives #3 and #4 arise in a “Zone of High Aspiration”.

The Symposium Report goes on to identify four key areas for focus that will help to advance a quality, efficient universal healthcare for all in the United States:

  1. Develop new health roles beyond just traditional medical care professionals and public health providers;
  2. Focus the health-tech sector on developing community health metrics;
  3. Cultivate new leadership for a healthy society; and
  4. Remove barriers to achieve better health outcomes and quality.

Full Report: http://www.rwjf.org/newsroom/product.jsp?id=74533&cid=xfb_rwjf

More on the Four Scenarios: http://debategraph.org/Poster.aspx?aID=77


[1] Health Leaders Look to 2032 for Opportunities to Improve the Health of the Nation at http://www.rwjf.org/newsroom/product.jsp?id=74533&cid=xfb_rwjf

 

Nonprofit Management

Supply Chain Forum to Discuss Trade and Travel Through U.S.-Canada Border

By Karen EvansComments Off

The Detroit Regional Chamber is hosting Translinked Supply Chain Forum: U.S. – Canada Regulatory Cooperation Council Presentation and Beyond the Border Action Plan Update on Friday, June 22 from 8:30-11:00 a.m. at the Detroit Regional Chamber offices on One Woodward Avenue in Detroit. This is certainly timely, coming on the heels of Canada’s offer to pay for the bulk of the costs for a new bridge between the US and Canada.
On the agenda is a discussion between TranslinkeD (a Detroit Regional Chamber initiative), the U.S. Department of Homeland Security, the Regulatory Cooperation Council’s Canadian Treasury Board Secretariat, and industry experts about how to maximize the opportunities for trade and travel through the U.S. – Canadian border.

Confirmed speakers include:

  • U.S. Representative Gary C. Peters, U.S. House of Representatives (MI-9)
  • Assistant Secretary Douglas A. Smith, Office of the Private Sector, U.S. Department of Homeland Security
  • Keith Devereaux, Office of International Affairs/Canada, U.S. Department of Homeland Security
  • Brian Masse, Member of Parliament (Windsor-West)
  • Glyn Chancey, Executive Director (Policy), Regulatory Cooperation Council, Canadian Treasury Board Secretariat
  • Carolyn Gawlik, Senior Director, Transportation, Distribution and Logistics Program, Detroit Regional Chamber
There is no cost to attend. If you are interested in transportation, distribution and logistics on what DRC calls “the world’s most important border crossing,” this is the place to be. Registration is here.
Experiences Around Town

Toronto Open House, June 9, 2012

By Nadia Shuayto2,175 Comments

The College of Management at Lawrence Tech University is hosting an open house on Saturday, June 9, 2012 from noon until 4:00 pm to recruit MBA students for the Toronto campus. Chris Balsingh, Mina Jena, and Nadia Shuayto are hosting the event at:

Delta Toronto East Hotel
2035 Kennedy Road
Toronto, MIT 3G2
Unionville Room

The Ontario market is interested in an American MBA with a focus on Theory and Practice. Based on recent conversation with students, they are very interested in earning a U.S. MBA from an accredited university.

For further information on the Toronto MBA Program, please visit the following website:

http://www.ltu.edu/management/international_toronto.asp

 

 

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For nonprofits of the health safety net, the times they are a-changin’

By College of Management1,173 Comments

The times are definitely a-changin’ for the leaders and the nonprofit organizations making up the health safety net.  As moderator/facilitator for Day #2 of the 2012 Healthy Safety Net Symposium of Blue Cross Blue Shield of Michigan (BCBSM) which just completed on Thursday, I learned more about their commitment and challenges of delivering on this mission of quality healthcare for all. This variety of nonprofits from across the State provide quality preventive and primary healthcare to anyone regardless of income or insurance. My respect for this experienced group dedicated volunteers, board members and staff (including many health providers) grows only larger.

The first day of the 2012 HSN Symposium provided an update on federal healthcare reform which largely consisted of many experienced and educated professionals concluding that we really don’t know what the US Supreme Course will do with the Affordable Care Act of 2010. My work on the 2102 HSN Symposium focused on the second day and our planning team decided to focus on things more in our control, that is, organizational sustainability and transformation of the health safety net organizations.  I served as moderator and facilitator for three panels of experts, practitioners and stakeholders who engaged the audience of about 250 for the entire day.

I started the day with some context on the topic of organizational sustainability. What it takes to sustain any nonprofit organization has been heavily examined, written about and discussed with some areas of consensus emerging. Though there is no one methodology coming forward, there is clear consensus that it all starts with leadership at both the executive and board level. A good example of a model for nonprofit sustainability comes from The TCC Group , a nationally recognized nonprofit consulting firm. The TCC Group has done extensive research on organizational sustainability at nonprofit organizations and developed what they refer to at The Sustainability Formula. In its simplest form, they present their formula as this:  “Leadership + Adaptability + Program Capacity = Sustainability”.

Leaders of healthy safety net (HSN) organizations know full well the realities of sustaining and transforming their nonprofit organizations however the pace of the real-time decision-making they engage in has exponentially increased.  Along with restructuring that all U.S. nonprofits today face (For nonprofits, time to end business-as-usual ) , the leaders of these safety net organizations have the added dynamic of operating in the midst of the historic change in healthcare reform. Given the lack of clarity on many key issues, they are in need of relevant, timely information to inform their vision and planning. This was an over-arching goal of the 2012 HSN Symposium.

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