1. Sub-national Estimates in the NCVS
Bureau of Justice Statistics
June 7, 2012

2. Utility of Sub-national Estimates
Crime is always local and sometimes national.
NCVS is designed to provide national estimates.
National estimates are useful for many purposes.
Sub-national estimates can be useful both for stakeholders at the national level as well as states and large cities.

3. BJS’ Approach to the Issue
Identify estimates that can be made with the NCVS data and are of sufficient precision.
Determine if these estimates are useful or how they can be made useful to stakeholders.
This webinar is one of a number of meetings where we can present preliminary products and work with stakeholders to determine their utility.

4. Outline of the Presentation
Present general outline of strategies for producing sub-national estimates.
Present various products using these various strategies and get your reaction.
Can the product be understood?
Can you find yourself in these data?
Is the information useful?
When would you use it?
Are all important distinctions made?

5. Range of Strategies
OPTION
STRATEGY 1
Direct estimates of rolling averages with core data. 2
Generic area estimates. 3
Direct estimates with boost and sample reallocation. 4
Modeled estimates with NCVS data and available auxiliary data. 5
Blended estimates with low cost boost. 6
Low cost independent local surveys. 7
Police administrative record frame.

6. Definitions
Direct estimates are made exclusively with actual samples from the NCVS.
Indirect estimates are modeled estimates using correlates of victimization with existing NCVS sample, if available, in the jurisdiction.
Sample boosts refer to increases in sample size.
Reallocation refers to redistributing the sample so that it is more suitable for sub-national rather than national estimates.
Accumulation (rolling averages) is the combining of annual samples for greater precision, e.g. 3-years, 5-years.

7. Generic Area Estimates
Sometimes it is sufficient to have an estimate from areas “like” yours.
Estimates for areas “like” yours are formed by taking all of the NCVS interviews conducted in areas like yours.
Areas “like” yours are formed by identifying a number of attributes and defining as similar those areas that have similar values on these attributes.
We have illustrations with the public use files but other area identifiers are available in Census data.

8. Generic Areas Create a typology of “like places” using available data
Region: Northeast, Midwest, South, West
Population size:
Not in a place
Under 10,000
10,000-49,999
50,000-99,999
100, ,999
250, ,999
500, ,999
1,000,000 or more
MSA status: Rural, Suburban, Urban
Typology based on combination: MSA X Region X Population size
Example: “city with a population of 250, ,000 in the Northeast” represents places such as Buffalo, NY, and Pittsburgh, PA.

9. Violent Crime Rates by Year and Type of Place
% change
Example
Very Large Cities in the Northeast 54 14
-73.7
New York, Boston
Very Large Cities in the Midwest 76 32
-57.5
Chicago
Very Large Cities in the South 56 37
-34.9
Houston
Very Large Cities in the West 57 22
-61.4
Los Angeles
Large cities in the Northeast 45 40
-9.4
Baltimore
Large Cities in the Midwest
102 28
-72.3
Indianapolis
Large Cities in the South 70 25
-64.3
Jacksonville
Large Cities in the West 83 24
-71.0
San Jose
Very Large Suburban Counties in the NE 13 16
25.2
Very Large Suburban Counties in the MW 64
-65.0
Very Large Suburban Counties in the South 21
-54.2
Very Large Suburban Counties in the West 65 26
-60.1
Small Rural Places in the Northeast 61 44
-26.8
Small Rural Places in the Midwest 38 19
-50.4
Small Rural Places in the South
Small Rural Places in the West 81
-74.3

10. Burglary Rates Per 1,000 1996-98 2008-10 % change
Very large cities in the Northeast
27.12
11.68
-56.93
Very Large cities in the Midwest
79.52
48.25
-39.33
Very large cities in the South
60.69
46.52
-23.35
Very large cities in the West
70.14
21.67
-69.11
Large cities in the Northeast
22.42
18.58
-17.15
Large cities in the Midwest
82.57
67.24
-18.57
Large cities in the South
77.65
44.55
-42.62
Large cities in the West
68.35
24.93
-63.53
Large suburban counties in the NE
71.43
14.32
-79.96
Large suburban counties in the Midwest
27.58
22.24
-19.38
Large suburban counties in the South
56.41
35.28
-37.45
Large suburban countie in the West
54.36
15.52
-71.45
Small rural places in the Northeast
50.20
38.15
-24.00
Small rural places in the Midwest
41.01
26.13
-36.29
Small rural places in the South
40.02
49.36
23.34
Small rural places in the West
49.86
28.28
-43.27

11. Violent Crime Rates by Year and Type of Place
% change
Example
Northeast
Very Large Cities in the Northeast 54 14
-74
New York, Boston
Large cities in the Northeast 45 40 -9
Baltimore
Very Large Suburban Counties in NE 13 16 25
Small Rural Places in the Northeast 61 44
-27
Midwest
Very Large Cities in the Midwest 76 32
-57
Chicago
Large Cities in the Midwest
102 28
-72
Indianapolis
Very Large Suburban Counties in MW 64 22
-65
Small Rural Places in the Midwest 38 19
-50
South
Very Large Cities in the South 56 37
-35
Houston
Large Cities in the South 70
-64
Jacksonville
Very Large Suburban Counties in the South 21
-54
Small Rural Places in the South
West
Very Large Cities in the West 57
-61
Los Angeles
Large Cities in theWest 83 24
-71
San Jose
Very Large Suburban Counties in the West 65 26
-60
Small Rural Places in the West 81

12. Direct Estimates
NCVS has enough sample in some states to produce estimates of reasonable precision for violent crime.
Rolling up three years will allow us to make more precise estimates for big states and reasonable estimates for more states.
Estimates for prevalent classes of property crime are easier.
Sample boost and re-allocate allow more states to be included.

13. Boosts
Boosts determined by the desired precision of the total violent crime estimate for the specified number of states.
Relationship between boosts and states done in this manner because of the need to treat states as strata in sample reallocation.
State strata for all states with population over 8M (12).
CA,TX,NY,FL, IL, PA, OH,MI,GA,NC,NJ,VA
State strata for all states with population over 6M (17).
CA,TX,NY,FL, IL, PA,OH,MI,GA,NC,NJ,VA
WA,MA,IN,AZ,TN
State strata for all states with population over 5m (22).
MO, MD,WI,MN,CO

15. California: 3-year rolling averages for violence, by type of crime
Rates per 1,000
Type of Crime
Violence
21.1
18.7
15.7
14.4
Rape/sexual assault
0.8
0.6
0.5
Robbery
2.5
2.0
Aggravated assault
4.3
4.1
3.0
2.6
Simple assault
13.5
11.5
10.3
9.2
Burglary
23.7
22.3
20.7
20.3
Motor vehicle theft
12.6
12.3
11.6
9.9
Theft
123.1
119.5
113.7
117.0

16. California: NCVS and UCR Violent Crime Rates

17. California: NCVS and UCR Violent Crime Counts

20. 40 Largest Metropolitan Statistical Areas (MSAs) in NCVS
Core counties within these MSAs are defined as those self-representing primary sampling units that are common to the MSA definitions determined by the Office of Management and Budget for the 1970-based, 1980-based, and 1990-based sample designs. Each MSA is comprised of only the core counties and not all counties within the MSA of the 40 largest MSAs from January 1979 through December The 40 largest MSAs were determined based on the number of household interviews in an MSA.

22. Indirect Estimates
Methods that use NCVS data in combination with other data to make estimates for states and large cities.
Primary method for making estimates for the 28 smallest states as well as smaller cities without sufficient sample for direct estimates.
We are assessing various models using NCVS and UCR data over time.

23. UCR violent vs NCVS violent crime
LA is high and stays high
GA is average but then drops to lowest level
KY is lowest but then rises to national average.
Trends for each show a flattening for some in UCR (AL, GA) but a decline in the NCVS (AL, GA), others are more consistent (LA)

24. UCR vs NCVS for property crime
GA and AL high in UCR but then low in NCVS
KY is lowest in UCR but high in NCVS

25. Summary
For many years the NCVS ignored the issue of sub-national estimates.
In the last three years we have done some serious research and development work that has resulted in a multi-faceted approach to producing sub- national estimates.
The future and future directions of this program will depend on the response of stakeholder groups like you.
We need your feedback on how these estimates could contribute to your ability to do your job and to serve the clients that you serve.
Hopefully this session is the beginning of a dialogue on these issues.

26. Contact Information
Michael Planty, Victimization Statistics