Hi, my name is E.J., and my household is a nightmare for survey research firms.  We are a cell phone-only household.  Even worse, I maintain the same cell phone number which I first received in college which means that I maintain an area code which is at least two household moves ago. 



The National Center for Health Statistics reports that I am like a quarter of Americans that no longer maintain a landline phone, choosing to have cell phones only.  Furthermore, they found that one in seven homes have a landline but rarely use it.  It used to be that random digit dialing was the best way to get a nationally representative sample of households so that survey firms could talk to small samples of people and extrapolate to large populations of people.  But these continuing trends away from landlines (particularly for younger households) makes that really a challenge.  I looked around a bit to see if I could find a similar study for businesses (if you know of one, let me know!) but all I found was a 2004 NFIB study which showed "seventy-eight percent of small-business owners use a cell phone for business purposes."  I suspect that almost all self-employed businesses now predominently use cell service more than landlines, while it will be less of an issue for brick-and-mortar stores. 

If you want to follow this story more, then AAPOR or the JSM are likely to be the most helpful places to look for additional guidance. 

Related previous posts: The Impact of Cell Phones on Entrepreneurship Surveys, Exploring Mode Effects in Establishment Surveys

Update 5/24/2010: I saw a course listing at the Joint Program on Survey Methodology on this issue for March 23, 2011.

	Ben Spigel - 5/17/2010 4:33:18 PM
	This is a great point that I hadn't really thought of before. I wonder what this will mean for GEM? How important is the bias?

	E.J. Reedy - 5/18/2010 9:59:19 AM
	Ben, your point is a good one. Some of the more advanced groups, like Gallup, are finding methodologies to include cell phones in their survey frames: http://www.well-beingindex.com/methodology.asp (this is a U.S.-only study) but even well-funded groups like Gallup still do landline-only surveys in the international context. I haven't seen any studies looking at this internationally but I have seen that cell-phones in the developing world open up new possibilities for research such as providing cell phones to people for free if they provide constant feedback through short surveys or other things like that. For efforts which have an ongoing operation involving random digit dialing it will be a complicated next couple of years to find new methods which work while maintaining time-series continuity.