Disproportionality - Frequently Asked Questions

  1. What are these reports?
  2. What is the Weighted Risk Ratio (WRR)?
  3. What is the Alternate Risk Ratio (ARR)?
  4. Why have the numbers been calculated using the Operating and Resident District data?
  5. Why are WRRs used to assess disproportionality?
  6. What are the other values in the table?
  7. How is the Composition calculated?
  8. How is The Risk calculated?
  9. How is the Risk Ratio calculated?
  10. How do you calculate the WRR?
  11. How do you calculate the Alternate Risk Ratio?
  12. What does the WRR refer to in the table?
1. What are these reports?
These reports are designed to provide a snapshot of LEA performance in SPP Indicator 9 (Disproportionality – All Disabilities) and Indicator 10 (Disproportionality – By Disability Category). These Reports utilize Single Record Student Database (SRSD) population and Michigan Compliance Information System (MI-CIS) disability data to compute Composition, Risk, Risk Ratios, Weighted Risk Ratios (WRR) and Alternate Risk Ratios (ARR) by Operating and Resident District for each LEA by disability and race. Determinations of disproportionate representation of particular racial/ethnic groups have been based on the appropriate risk ratio; that is, the WRR, ARR, or basic risk ratio. Michigan examines the appropriate ratios for both the 'Operating' and 'Resident' District (see Question 4 below) and chooses the lower of the two in consideration of the state’s intervention scheme. Public School Academies (PSAs) have only one set of ratios since they are only tracked as operating districts. In order to be included in the analysis, districts needed to have 30 or more students with disabilities and 10 or more students in the racial/ethnic and disability group of interest. Michigan substitutes an Alternate Risk Ratio (ARR) in cases where a district meets the population requirements above, but where the comparison group (the number of students within the disability category of other racial/ethnic groups) is less than 10.
2. What is the Weighted Risk Ratio (WRR)?
WRR is used to assess the risk that students of a particular racial/ethnic category are over-represented among students receiving special education or related services. The Weighted Risk Ratio weights district level risk according to the racial/ethnic composition of the state. Methods for Assessing Racial/Ethnic Disproportionality in Special Education (please see page 32 for the equation)
3. What is the Alternate Risk Ratio (ARR)?
The Alternate Risk Ratio also assesses risk of over-representation in special education or related services. The ARR uses District Level risk in the numerator and State level risk for the comparison groups in the denominator. ARR is utilized to overcome the problem of small numbers in the comparison groups. Methods for Assessing Racial/Ethnic Disproportionality in Special Education (please see page 24 for the equation)
4. Why have the numbers been calculated using the Operating and Resident District data?
The WRRs were calculated using both Operating and Resident District data because of the limitations of using only one or the other. Using only the operating district data over-identifies districts with center-based programs. Utilizing only Resident district data places students receiving services in Public School Academies and schools of choice back in the districts where they live and not where they receive services. Where data were available, the tables present two sets of ratios for each racial/ethnic group, one for Operating District data, and the other for Resident district data. These ratios include the WRR, ARR, and the basic Risk Ratio.
5. Why are WRRs used to assess disproportionality?
WRR are used to assess disproportionality because it adjusts for comparison group variability by weighting the results by state racial/ethnic composition and allows for comparison of districts.
6. What are the other values in the table?
The tables include Composition (Comp), Risk, Risk Ratio (RR). These values along with the WRR and ARR have been presented for the 2014-2015 through 2015-2016 Federal Fiscal Years (FFYs).
7. How is the Composition calculated?
Composition (Comp) = District Population of racial/ethnic group in the disability category divided by the district’s total population of students with disabilities. Composition tells us the proportion of special education students that are of a particular racial/ethnic group.
8. How is The Risk calculated?
Risk = District Population of racial/ethnic group in the disability category divided by the district’s total population of the racial/ethnic group. Risk tells us the proportion of students of a particular racial/ethnic group that receive special education or related services.
9. How is the Risk Ratio calculated?
Risk Ratio (RR) = The risk of a particular racial/ethnic group in a particular disability category divided by the risk of all other racial/ethnic groups within that disability category. A Risk Ratio tells us the degree to which students from a particular racial/ethnic are more or less likely than their peers to receive special education services.
10. How do you calculate the WRR?
(Using Black students and All Disabilities as an example)
WRR Black All Disabilities = [(1-State composition of Black students) * District Risk for Black students All Disabilities]
Divided by
[(State composition of American Indian Students * District Risk for American Indian Students All Disabilities) + (State composition of Asian Students* District Risk for Asian Students All Disabilities) + (State composition of Hispanic Students * District Risk for Hispanic Students All Disabilities) + (State composition of White Students * District Risk for White Students All Disabilities)]
11. How do you calculate the Alternate Risk Ratio?
(Using Black students and All Disabilities as an example)
ARR Black All Disabilities = (District Risk for Black students All Disabilities)
Divided by (State level risk of comparison group)
12. What does the WRR refer to in the table?
The WRR in the table refers to the racial/ethnic and disability group of interest’s Weighted Risk Ratio.