The Fallacy of the Small Sample Size

Posted by on Aug 26 2009

When asking your customers for their opinion, do you ask enough people?

I recently asked my customers (all small busines owners) for feedback about what time of day, and day of week, they prefer to take teleclasses. When the first 10 or 20 responses came in, it was clear that everyone wanted teleclasses on Wednesdays at 7:00 PM. Wow! Who would have guessed?

I should re-schedule all my teleclasses, right?


When I re-discovered my patience and waited to get the full response from 300 or 400 people, the results were completely, totally different. When I waited for a larger sample size of survey results, new and important facts emerged: Wednesday was still popular, but of equal popularity was Tuesday and Thursday. More importantly, because I waited for a larger response group, I discovered the 7:00 PM timeslot slide in popularity, to be replaced strongly by 12:00 – 2:00 timeframe.

Take the “What Time for Teleclasses?” survey here.

Had I made business decisions based on the first 20 responses, I would have created a disaster.

When you have a business idea or decision to make, do you just ask five or ten people? Stop destroying your business by using small sample sizes in your surveys! The more people you ask, the better quality of results you’ll get.

Read more about the fallacy of small sample sizes, also known as “hasty generalizations:”


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Category: Running a Strong & Efficient Business