Table 11. Measures of Error for County Estimates by Use of Groups of Three Ratio-Correlation Variables

Source:  U.S. Bureau of the Census
Internet Release date:  June 20, 1997

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           |        |          |                              MEASURES OF DIFFERENCE
           |        |          |------------------------------------------------------------------------------- 
           |        |          |  Mean Algebraic   |   Mean Absolute   |                   |
           | Number |   Number |   Percent Error   |   Percent Error   |       Median      |  90th Percentile
           |     of |       of |-------------------|-------------------|-------------------|-------------------
 Variables | States | Counties |    With | Without |    With | Without |    With | Without |    With | Without
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S,B,I            17        977       2.0       2.0       3.2       3.7       2.5       2.8       6.7       6.7
B,D,I            16        812       2.2       1.9       3.6       3.5       3.0       2.6       7.1       7.1
M,B,I            14        662       1.4       2.2       2.9       3.7       2.3       2.9       6.3       6.3
S,B,D            13        737       2.1       1.9       3.4       3.5       2.8       2.7       6.8       6.8
M,S,I            12        655       2.0       2.0       3.2       3.6       2.5       2.8       6.5       6.5
M,B,D            12        591       1.6       2.1       3.2       3.6       2.7       2.7       6.4       6.4
S,D,I            12        673       2.3       1.9       3.7       3.4       3.0       2.6       7.2       7.2
M,S,B            12        586       1.0       2.3       3.1       3.6       2.2       2.8       6.6       6.6
S,B,A            11        868       1.9       2.0       3.0       3.7       2.3       2.9       6.3       6.3
M,D,I            10        484       1.9       2.0       3.2       3.6       2.7       2.7       6.4       6.4
B,I,A             8        628       2.0       2.0       3.2       3.6       2.5       2.7       6.8       6.8
S,I,A             8        560       1.9       2.0       3.1       3.6       2.6       2.7       6.5       6.5
B,D,A             7        561       2.1       2.0       3.5       3.5       3.0       2.6       7.0       7.0
M,S,D             7        383       1.8       2.0       3.3       3.5       2.6       2.7       6.5       6.5
M,B,A             6        530       1.3       2.2       3.1       3.6       2.4       2.8       6.5       6.5
S,D,A             5        390       2.1       2.0       3.5       3.5       3.1       2.6       6.7       6.7
D,I,A             5        349       2.4       1.9       3.8       3.4       3.3       2.6       7.6       7.6
M,I,A             4        328       1.2       2.1       2.8       3.6       2.2       2.8       6.3       6.3
M,S,A             4        343       1.3       2.1       2.9       3.6       2.2       2.8       5.9       5.9
M,D,A             3        271       1.3       2.1       3.4       3.5       3.0       2.7       6.7       6.7
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(S=School Enrollment, M=Medicare Enrollment, B=Births, D=Deaths, I=IRS Returns, A=Automobile Registration)