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981.
This paper analyzes sources of error in the two major methods we use to measure crime in America—official police statistics and victimization surveys. The two produce quite different pictures of the volume and distribution of crime, but it is not clear that this is because victim-based statistics are “accurate.” Each measurement procedure has its characteristic errors, some of which it shares with the other. Comparisons of official and survey data on crime are helpful in revealing the dimensions of these error terms, and they point out the analyses which must be conducted if we are to specify their exact proportions.  相似文献   
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On 21 February 1890, two woodsmen working in densely wooded Blenheim Swamp in southern Ontario, Canada, stumbled upon the dead body of a young Englishman who had been killed by two gunshot wounds to the head. He was identified as Frederick Benwell by a married couple, the Birchalls, who had traveled with him and another man, Pelly, from England to New York City by ship about 1 week before. The Birchalls lied regarding Benwell's subsequent movements. Questioning Pelly revealed to Detective John Murray that both Pelly and Benwell had replied separately to Birchall's advertisement for young men of means to become partners with him in a large Canadian farm, a deposit first being required. Birchall had been observed taking Benwell from Buffalo, New York, to Blenheim Swamp, for in reality there was no farm. There he had shot Benwell, leaving the body partially exposed. He then tried unsuccessfully to lure Pelly to his death in Niagara Falls. The Birchalls were arrested. Reginald Birchall was tried, convicted, and hanged. His attempt, including murder, to turn the so-called farm pupil colonization scheme to his own benefit had been frustrated by the dogged work of the master Canadian detective Murray.  相似文献   
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A digoxin-like immunoreactive substance (DLIS) has been reported in the serum of infants not receiving digoxin. This study was undertaken to determine if DLIS is present in the postmortem blood and tissues of infants or children and whether the endogenous substance could interfere with forensic toxicological analysis in suspected overdose. Ninety blood specimens taken from the heart at autopsy of children or infants were screened for DLIS using commercial radioimmunoassay kits. The average age at death in these cases was 8.6 months, the median age was 2 months. DLIS equivalent to 0.25 to 2.0 ng/mL digoxin was found in one third of the cases. The incidence of positive findings was 5/6 stillborns, 10/45 Sudden Infant Death Syndrome (SIDS), 10/15 deaths as a result of infection, 4/7 homicides, 1/8 deaths caused by congenital defects, and 0/9 accidental deaths. The body distribution of DLIS was investigated and highest levels were found in the liver. Findings of DLIS in blood were correlated with renal failure, (elevated vitreous urea nitrogen), electrolyte imbalance, and liver trauma. Apparent concentrations were in the equivalent therapeutic range of digoxin and would not be confused with accidental or intentional overdose with digoxin.  相似文献   
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