Note: error bars based on standard deviation of rates CLICK TO ENLARGE |
Even though the rate increased in 2012-13 (4.2656 incidents per 100 students) from 2011-2012 (4.055 incidents per 100 students) the official district document reads: "The report shows a significant drop in the number of incidents over five years." A look at the "per 100" rates indicates no such "significant drop"at all and in fact the rates of violence and vandalism peaked during the 2009-10 and 2010-2011 school years (Carter/Rusak/Toback/Kids First). Moreover, 2012-2013 saw a slight RISE in the violence and vandalism rate compared to the previous year.
"Rates take into account the size of the population, so comparison can be made across different population groups. By using rates instead of raw numbers, the occurrence of violence and vandalism in one group or cohort can be fairly compared with another." -Material in any Introduction to Statistics CourseFurthermore, when you add error bars to the charts (see chart above), you realize the claims of "significantly less" are even less credible and accurate.
In other posts I have indicated that comparable data (school year 2011-12) around New Jersey is Atlantic City (2.13 incidents per 100 students), Camden (1.6 incidents per 100 students), Newark (.9 incidents per 100 students), and Patterson (1.0 incidents per 100 students).
note: While a new category was added to the EEVRS report in 2011-12 (HIB- Harassment, Intimidation, and Bulling), these incidents were previously responsibly reported under other categories on the form. The fact that the state created a new category to identify these incidents do not mean the incidents were not previously tallied.
Data Used in Analysis
2008-09 | 2009-10 | 2010-11 | 2011-12 | 2012-13 | |
Enroll | 1873 | 1954 | 1816 | 1726 | 1641 |
Incidents | 91 | 101 | 97 | 70 | 70 |
per 100 | 4.858 | 5.168 | 5.3414 | 4.055 | 4.2656 |