Juvenile Court Statistics 2005. - Office of Juvenile Justice and ...

Appendix A: Methodspotential donor records defined bystrata, year of disposition, and intakedecision.Weighting to produce national estimates.The Archive employs an elaboratemultivariate procedure thatassigns a weight to each record inthe national case-level database that,when used in analysis, yields nationalestimates of juvenile court activity.The weights incorporate a number offactors related to the size and characteristicsof juvenile court caseloads:the size of a community; theage and race composition of its juvenilepopulation; the age and raceprofile of the youth involved in juvenilecourt cases; the courts’ responsesto the cases (intake decision,detention, adjudication, and disposition);and the nature of each court’sjurisdictional responsibilities (i.e.,upper age of original jurisdiction).The basic assumption underlying theweighting procedure is that similarlegal and demographic factors shapethe volume and characteristics ofcases in reporting and nonreportingcounties of comparable size and features.The weighting proceduredevelops independent estimates forthe number of petitioned delinquencycases, nonpetitioned delinquencycases, and petitioned status offensecases handled by juvenile courtsnationwide. Identical statistical proceduresare used to develop all caseestimates.As noted earlier, all U.S. counties areplaced into one of four strata basedon the size of their youth populationages 10 through 17. In the first stepto develop the weights, the Archivedivides the youth 10-17 populationfor each stratum into three agegroups: 10- through 15-year-olds,16-year-olds, and 17-year-olds. Thethree age groups are further subdividedinto four racial groups: white,black, American Indian (includingAlaskan Native), and Asian (includingNative Hawaiian and Other PacificIslander). Thus, juvenile residentpopulation estimates are developedfor 12 age/race categories in eachstratum of counties.The next step is to identify withineach stratum the jurisdictions thatcontributed to the Archive case-leveldata consistent with JCS reportingrequirements. The populations ofthese case-level reporting jurisdictionswithin each stratum are thendeveloped for each of the 12age/race categories. The nationalcase-level database is summarized todetermine within each stratum thenumber of court cases that involvedyouth in each of the 12 age/race populationgroups. Case rates (numberof cases per 1,000 juveniles in thepopulation) are then developed forthe 12 age/race groups within eachof the four strata.For example, assume that a total of3,507,000 white youth ages 10–15resided in those stratum 2 countiesthat reported JCS-compatible caseleveldata to the Archive. If theArchive’s case-level database showsthat the juvenile courts in thesecounties handled 56,039 petitioneddelinquency cases involving whiteyouth ages 10 through 15, the numberof cases per 1,000 white youthages 10–15 for stratum 2 would be16.0, or:(56,039 / 3,507,000) x 1,000 = 16.0Comparable analyses are then usedto establish the stratum 2 case ratesfor black youth, American Indianyouth, and Asian youth in thesame age group (56.4, 25.5, and 9.4,respectively).Next, information contained in thenational court-level database is introduced,and stratum-level case ratesare adjusted accordingly. First, eachcourt-level statistic is disaggregatedinto the 12 age/race groups. Thisseparation is accomplished byassuming that, for each jurisdiction,the relationships among thestratum’s 12 age/race case rates(developed from the case-level data)are paralleled in the court-level data.For example, assume that a jurisdictionin stratum 2 with an upper ageof original juvenile court jurisdictionof 15 reported it processed 600 casesduring the year. Also assume thatthis jurisdiction had a juvenile populationof 12,000 white youth, 5,000black youth, 500 American Indianyouth, and 1,500 Asian youth. Thestratum 2 case rates for each racialgroup in the 10–15 age group wouldbe multiplied by the correspondingpopulation to develop estimates ofthe proportion of the court’s caseloadthat came from each age/racegroup, as follows:White:(16.0 x 12,000) / [(16.0 x 12,000) +(56.4 x 5,000) + (25.5 x 500) +(9.4 x 1,500)] = 38.3%Black:(56.4 x 5,000) / [(16.0 x 12,000) +(56.4 x 5,000) + (25.5 x 500) +(9.4 x 1,500)] = 56.3%American Indian:(25.5 x 500) / [(16.0 x 12,000) +(56.4 x 5,000) + (25.5 x 500) +(9.4 x 1,500)] = 2.6%Asian:(9.4 x 1,500) / [(16.0 x 12,000) +(56.4 x 5,000) + (25.5 x 500) +(9.4 x 1,500)] = 2.8%The jurisdiction’s total caseload of600 would then be allocated basedon these proportions. In this example,it would be estimated that 38.3%of all cases reported in the jurisdiction’saggregate statistics involvedwhite youth, 56.3% involved blackyouth, 2.6% involved AmericanIndian youth, and the remaining 2.8%involved Asian youth. When theseproportions are applied to a reportedcourt-level caseload statistic of600 cases, this jurisdiction is estimatedto have handled 230 cases involvingwhite youth, 338 cases involvingblack youth, 15 cases involving98Juvenile Court Statistics 2005