Guns at Home

According to the New York Times in the article "Share of Homes With Guns Shows 4-Decade Decline" from March 9th 2013, they use General Social Survey (GSS) data from the University of Chicago to conclude that in the past 40 years there has been a decline in gun ownership throughout the entirety of all people in the nation. Interestingly enough this survey data readily contains the original question, "237. Do you happen to have in your home (IF HOUSE: or garage) any guns or revolvers?" and the respondents have three options for disclosure, Yes, No, and Refuse to Answer (Smith et al., 2011). The surveys were conducted mainly as person to person interviews and less so over the phone, but since 2002 some have been administered by Computer-assisted Personal Interviewing. The GSS also reports that they attempt to receive a representative sample from across the entire country.

The author of the New York Times article goes so far as to say, "The household gun ownership rate has fallen from an average of 50 percent in the 1970s to 49 percent in the 1980s, 43 percent in the 1990s and 35 percent in the 2000s, according to the survey data, analyzed by The New York Times" (Tavernise and Gebeloff, 2013). The difference among the percentages of 50% to 49% ownership from the 1970's to 1980's as a significant "decline," I disagree with as the difference between these values to be rather inconsequential when compared with standard errors. The standard error for a 0.5 probability with their sample size, roughly 1500 people, is 1.29%. This would serve to invalidate their title of a four decade decline. If we look at the data collected by the GSS for the following decades, the data shows progression similar to that reported in the New York Times article, when using the 1972-2006 data set for gun ownership.

Upon performing a simple linear regression of the percentage of people reporting they have a gun in their home from 1972 to 2006, I found that with an R-squared of 0.7288 that there appears to be a decrease of 0.659% per year of people who acknowledge that they store a firearm in their home. While an R-squared of 0.7288 is relatively ambiguous in my mind it does serve to coincide with the values I calculated for people who answered no to this same survey question over the same period of time, at an R-squared of 0.6718 and a yearly increase of 0.573%. Also if performing a simple linear regression for data collected solely after 1980 we find that there is a decrease of 0.897% per year with an R-squared of 0.81. Perhaps if the New York Times analysts would have performed analysis on the entire data set they would have been able to avoid using an incorrect title.

While the difference in percentages calculated for the years after the 1980's are more significant than that of their associated error there may also be several flaws within the data collected. The majority of these surveys were conducted in person to person interviews which may have created some form of bias like we discussed in class. Also the question itself posed by the GSS only accounts for firearms stored in your home or garage, which the New York Times report refers to as gun ownership. Respondents may have owned firearms and not stored them in their home or garage. I only mention these possibilities as organization such as the NRA report that 40-45% of US households have firearms on their premisses, though the NRA do not actually have any survey data to back it up (Agresti and Smith, 2010).

Please note: Agresti and Smith's Just Facts website is a pro firearm website that states, "Although the NRA does not state that this data is derived from surveys, Just Facts found that it is consistent with a broad range of surveys." which coincidentally these broad surveys Just Facts fails to report...

"Firearms Fact Card, 2010." National Rifle Association, January 20, 2010. http://www.nraila.org/Issues/FactSheets/Read.aspx?ID=83

"Gun Control Facts." By James D. Agresti and Reid K. Smith. Just Facts, September 13, 2010. Revised 2/11/13. http://justfacts.com/guncontrol.asp

Smith, Tom W, Peter Marsden, Michael Hout, and Jibum Kim. General social surveys, 1972-2010[machine-readable data file] /Principal Investigator, Tom W. Smith; Co-Principal Investigator, Peter V. Marsden; Co-Principal Investigator, Michael Hout; Sponsored by National Science Foundation. --NORC ed.-- Chicago: National Opinion Research Center [producer]; Storrs, CT: The Roper Center for Public Opinion Research, University of Connecticut [distributor], 2011.

Tavernise S., and Gebeloff R. "Share of Homes With Guns Shows 4-Decade Decline." New York Times 09 Mar 2013, 1-2. Web. 10 Mar. 2013. <http://www.nytimes.com/2013/03/10/us/rate-of-gun-ownership-is-down-survey-shows.html?hp&_r=0>.