Teacher:In this task, you are given a text of many news articles seperated by special token "|||||". Your task is to summarize them.
Teacher: Now, understand the problem? Solve this instance: 108 Pages Posted: 31 May 2014 Last revised: 5 Sep 2014 
  
 There are 2 versions of this paper 
  
 Date Written: September 4, 2014 
  
 Abstract 
  
 For over a decade, there has been a spirited academic debate over the impact on crime of laws that grant citizens the presumptive right to carry concealed handguns in public – so-called right-to-carry (RTC) laws. In 2004, the National Research Council (NRC) offered a critical evaluation of the “More Guns, Less Crime” hypothesis using county-level crime data for the period 1977-2000. 15 of the 16 academic members of the NRC panel essentially concluded that the existing research was inadequate to conclude that RTC laws increased or decreased crime. One member of the panel thought the NRC's panel data regressions showed that RTC laws decreased murder, but the other 15 responded by saying that “the scientific evidence does not support” that position. 
  
  
  
 We evaluate the NRC evidence, and improve and expand on the report’s county data analysis by analyzing an additional six years of county data as well as state panel data for the period 1979-2010. We also present evidence using both a more plausible version of the Lott and Mustard specification, as well as our own preferred specification (which, unlike the Lott and Mustard model presented in the NRC report, does control for rates of incarceration and police). While we have considerable sympathy with the NRC’s majority view about the difficulty of drawing conclusions from simple panel data models and re-affirm its finding that the conclusion of the dissenting panel member that RTC laws reduce murder has no statistical support, we disagree with the NRC report’s judgment on one methodological point: the NRC report states that cluster adjustments to correct for serial correlation are not needed in these panel data regressions, but our randomization tests show that without such adjustments the Type 1 error soars to 22-73 percent. 
  
  
  
 Our paper highlights some important questions to consider when using panel data methods to resolve questions of law and policy effectiveness. We buttress the NRC’s cautious conclusion regarding the effects of RTC laws by showing how sensitive the estimated impact of RTC laws is to different data periods, the use of state versus county data, particular specifications (especially the Lott-Mustard inclusion of 36 highly collinear demographic variables), and the decision to control for state trends. 
  
  
  
 Across the basic seven Index I crime categories, the strongest evidence of a statistically significant effect would be for aggravated assault, with 11 of 28 estimates suggesting that RTC laws increase this crime at the .10 confidence level. An omitted variable bias test on our preferred Table 8a results suggests that our estimated 8 percent increase in aggravated assaults from RTC laws may understate the true harmful impact of RTC laws on aggravated assault, which may explain why this finding is only significant at the .10 level in many of our models. Our analysis of the year-by-year impact of RTC laws also suggests that RTC laws increase aggravated assaults. Our analysis of admittedly imperfect gun aggravated assaults provides suggestive evidence that RTC laws may be associated with large increases in this crime, perhaps increasing such gun assaults by almost 33 percent. 
  
  
  
 In addition to aggravated assault, the most plausible state models conducted over the entire 1979-2010 period provide evidence that RTC laws increase rape and robbery (but usually only at the .10 level). In contrast, for the period from 1999-2010 (which seeks to remove the confounding influence of the crack cocaine epidemic), the preferred state model (for those who accept the Wolfers proposition that one should not control for state trends) yields statistically significant evidence for only one crime – suggesting that RTC laws increase the rate of murder at the .05 significance level. It will be worth exploring whether other methodological approaches and/or additional years of data will confirm the results of this panel-data analysis and clarify some of the highly sensitive results and anomalies (such as the occasional estimates that RTC laws lead to higher rates of property crime) that have plagued this inquiry for over a decade. ||||| Posted: 17 Apr 1998 
  
 Abstract 
  
 Using cross-sectional time-series data for U.S. counties from 1977 to 1992, we find that allowing citizens to carry concealed weapons deters violent crimes and it appears to produce no increase in accidental deaths. If those states which did not have right-to-carry concealed gun provisions had adopted them in 1992, approximately 1,570 murders; 4,177 rapes; and over 60,000 aggravated assaults would have been avoided yearly. On the other hand, consistent with the notion of criminals responding to incentives, we find criminals substituting into property crimes involving stealth and where the probabilities of contact between the criminal and the victim are minimal. The largest population counties where the deterrence effect on violent crimes is greatest are where the substitution effect into property crimes is highest. Concealed handguns also have their greatest deterrent effect in the highest crime counties. Higher arrest and conviction rates consistently and dramatically reduce the crime rate. Consistent with other recent work, the results imply that increasing the arrest rate, independent of the probability of eventual conviction, imposes a significant penalty on criminals. The estimated annual gain from allowing concealed handguns is at least $6.214 billion. ||||| Right-to-carry gun laws linked to increase in violent crime, Stanford research shows 
  
 Stanford research reaffirms that right-to-carry gun laws are connected with an increase in violent crime. This debunks – with the latest empirical evidence – earlier claims that more guns actually lead to less crime. 
  
 Vartanov Anatoly/ Shutterstock Research co-authored by law Professor John Donohoe finds that right-to-carry gun laws are linked to an increase in violent crime. 
  
 New Stanford research confirms that right-to-carry gun laws are linked to an increase in violent crime. 
  
 Right-to-carry or concealed-carry laws have generated much debate in the past two decades – do they make society safer or more dangerous? 
  
 While there is no federal law on concealed-carry permits, all 50 states have passed laws allowing citizens to carry certain concealed firearms in public, either without a permit or after obtaining a permit from local government or law enforcement. 
  
 Recently published scholarship updates the empirical evidence on this issue. Stanford law Professor John J. Donohue III, Stanford law student Abhay Aneja and doctoral student Alexandria Zhang from Johns Hopkins University were the co-authors of the study. 
  
 "Trying to estimate the impact of right-to-carry laws has been a vexing task over the last two decades," said Donohue, the C. Wendell and Edith M. Carlsmith Professor of Law, in an interview. 
  
 He explained that prior research based on data through 1992 indicated that the laws decreased violent crime. But in 2004, he noted, the National Research Council issued a report that found that even extending this data through 2000 revealed no credible statistical evidence these particular laws reduced crime. 
  
 'Totality of the evidence' 
  
 Now, Donohue and his colleagues have shown that extending the data yet another decade (1999-2010) provides the most convincing evidence to date that right-to-carry laws are associated with an increase in violent crime. 
  
 "The totality of the evidence based on educated judgments about the best statistical models suggests that right-to-carry laws are associated with substantially higher rates" of aggravated assault, rape, robbery and murder, said Donohue. 
  
 The strongest evidence was for aggravated assault, with data suggesting that right-to-carry (RTC) laws increase this crime by an estimated 8 percent – and this may actually be understated, according to the researchers. 
  
 "Our analysis of the year-by-year impact of RTC laws also suggests that RTC laws increase aggravated assaults," they wrote. 
  
 The evidence is less strong on rape and robbery, Donohue noted. The data from 1979 to 2010 provide evidence that the laws are associated with an increase in rape and robbery. 
  
 The murder rate increased in the states with existing right-to-carry laws for the period 1999-2010 when the "confounding influence" of the crack cocaine epidemic is controlled for. The study found that homicides increased in eight states that adopted right-to-carry laws during 1999-2010. 
  
 Research obstacles, next step 
  
 "Different statistical models can yield different estimated effects, and our ability to ascertain the best model is imperfect," Donohue said, describing this as the most surprising aspect of the study. 
  
 He said that many scholars struggle with the issue of methodology in researching the effects of right-to-carry laws. But overall, his study benefits from the recent data. 
  
 Donohue suggested it is worth exploring other methodological approaches as well. "Sensitive results and anomalies – such as the occasional estimates that right-to-carry laws lead to higher rates of property crime – have plagued this inquiry for over a decade," he said. 
  
 Media Contact 
  
 John J. Donohue III, Stanford Law School: (650) 721-6339, donohue@law.stanford.edu 
  
 Clifton B. Parker, Stanford News Service: (650) 725-0224, cbparker@stanford.edu ||||| Laws in all 50 states permitting people to carry concealed firearms in public have been connected to a rise in violent crimes, according to a new report from researchers at Stanford and Johns Hopkins universities. 
  
 The report, published in September and issued as a National Bureau of Economic Research Working Paper last week, adds to a series of studies over the last decade tending to discredit the "more guns, less crime" hypothesis, which argues that right-to-carry laws serve as crime deterrents by allowing ordinary Americans to better protect themselves. 
  
 The new findings suggest that right-to-carry laws are "associated with substantially higher rates" of aggravated assault, rape and robbery, Stanford law professor John J. Donohue III, one of the study’s three authors, explained in a press release on Friday. Stanford law student Abhay Aneja and Johns Hopkins doctoral student Alexandria Zhang co-authored the report. 
  
 Among violent crimes, the most significant increase came in aggravated assault, which may have risen by nearly 33 percent, according to the report. The researchers also found that from 1999 to 2010, murder rates rose in eight states that adopted right-to-carry laws. 
  
 In 2012, there were nearly 9,000 firearm homicides in the United States. A year earlier, more than 21 percent of an estimated 751,131 aggravated assaults in the nation were committed with firearms. 
  
 A decade ago, the National Research Council found "no credible evidence" associating concealed-carry laws with either a drop or a rise in violent crimes. It cited weak research models and a lack of sufficient data at the time. 
  
 While the NRC panel relied on county-level crime data from 1977 to 2000, the latest report used data from 1979 to 2010, covering an additional 10 years in which right-to-carry laws expanded and adding a net six more years of county and state records. |||||
Student:
For years, gun-rights advocates cited a 1997 paper's claim that "allowing citizens to carry concealed weapons deters violent crimes." The National Research Council came out with its own take in 2004, saying there was "no credible evidence that 'right-to-carry' laws … either decrease or increase violent crime." Now researchers from Stanford University have confronted the "vexing task" of extending that data even further, and come to their own conclusion: that right-to-carry (or concealed-carry) laws are actually linked to an increase in violent crimes. The researchers say the strongest evidence concerned aggravated-assault data, which indicates that RTC laws are tied to an 8% increase in such assaults. Stats also seem to link RTC laws with "substantially higher rates" of rape, robbery, and murder. Lead researcher John Donohue explains that research used for the 1997 study relied on stats that only went from 1977 to 1992; the NRC extended that data up through the year 2000. Donohue's team took it to 2010, thereby including a decade that saw RTC laws grow in popularity, the Huffington Post notes (all 50 states now have a concealed-carry law, according to Stanford). The new research also "corrected a number of flaws in the data" by tapping into new statistical methods, according to the director of the Johns Hopkins Center for Gun Policy and Research. Still, Donohue admits it's no easy task: "Different statistical models can yield different estimated effects, and our ability to ascertain the best model is imperfect," he says in the press release. (Illinois was the last state to approve a concealed-carry law.)