57 Guns in America
Philp J. Cook and Jens Ludwig

1. Facts:

1.1. 200 million guns are in private hands.

1.2. Widespread ownership of firearms has an important impact on the quality of life in America.

2. Gun Ownership--Prevalence:

1957: 50% American households own guns.

1994: 35% American households own guns.

　

3. Defensive Gun Uses (DGUs)—NSPOF Estimates

3.1. DGUs are invoked as a measure of the public benefits of private gun ownership

3.2. DGUs: 10800 per year (according to “National Crime Victimization Survey (NCVS)).

2.5 million per year (according to 1994 telephone survey)

3.3. NSPOF Survey: Each of the respondents was asked the question, “Within the past 12 months have you yourself used a gun, even if it was not fired to protect yourself or someone else or for the protection of property at home, work, or elsewhere?” etc.

　

4. Some Troubling Comparisons:

5. False Positives

5.1.Respondents might falsely provide a positive response to the DGU questions

5.2. The explanation for the difference between the 108,000 NCVS estimate and several million of NSPOF and Kleck and Gertz estimate: NCVS avoids the false-positive problem by limiting DGU questions to persons who first reported that they were crime victims.

6. Unclear Benefits and Costs form Gun Uses

The NSPOF does not provide much evidence on whether consumers who buy guns for protection against crime get their money’s worth. The NSPOF based estimate of millions of DGUs each year greatly exaggerates the true number.