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APPENDIX F M.O.E. Sampling Plan Development
Pages 193-234

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From page 193... ... The selection process designated Me 22 sites noted above, resuming In a highway functional class distribution as follows: 6 Rural Interstates, 6 Rural Pnncipal Arterials, 3 Rural Minor Arterials, 4 Urban Interstates, and 3 Urban Primary Arterials . The resulting distribution by region is as follows: ~ Central, 5 West, 4 Atlantic, 5 South. Read the entire page →
From page 194... ... Sites selected for sampling plan development % Buck volume Functional Class ~ r Low ~Medium j Rural Interstates T WA7409 ~VAl023 NS6802 TN1023 RuralPrincipalArte- T FL4109 ~RI7401 nals FL4138 KSI006 . Rural Minor Arterials T VA1002 ~ IN2009 None KS1005 . Read the entire page →
From page 195... ... At least two sites were needed per cell to provide an estimate of within cell variability needed for developing sample size. In the case of urban interstates with low truck volumes arid urban primary arterials with medium truck volume, only one site was available for those cells so cell sample size could not be developed. Read the entire page →
From page 196... ... Description of Vehicle Classifications vCs vc6 vc7 vc8 vcs vc 10 VC 11 vc 12 vc 13 Two-axle Single Unit Three-axle Single Unit Four or More Axle Single Unit Four or Less Axle Single Trailer Five-axle Single Trailer Six or More Axle Single Trailer Five or Less Axle Multi-Trailer Six-Axle Multi-Trailer Seven to More Axle Multi-Trailer SITE NUMBER REQUIREMENTS FOR ESALs AND EXCESS ESALs Sample size estimates are determined herein for a wide range of precision levels for two M.O.E.'s - percent Excess ESALs and average ESALs. The main purpose in providing estimates over a range of precisions is to give the user some idea of the maximum and minimum sample size requirements Mat exist based on these data. Read the entire page →
From page 197... ... All sample sizes are based on the five- percent significance level with 80% power of detecting the corresponding precisions. Table 5 lists summary statistics, table 6 lists sample sizes for the M.O.E. Read the entire page →
From page 198... ... : Percent Charge to be detected Vehicle Class \| 5 l 10 \| 15 20 l 31 8 1 3 . Read the entire page →
From page 199... ... For vehicle class 7 to declare a 30 percent reduction in average ESALs as a statistically significant reduction due to enforcement, three sites are needed. To detect this for vehicle class 8, 38 sites are needed. Read the entire page →
From page 200... ... Table 8 lists summary statistics, table 9 lists sample sizes for the M.O.E. percent Excess ESALs and Table 10 lists these for the M.O.E. Read the entire page →
From page 201... ... Percent Change to be detected Vehicle Class ~5 10 ~15 20 5 1 136 34 1 15 6 1 180 45 1 20 7 1 524 131 1 58 8 1 104 26 1 11 9 1 284 71 1 32 10 1 188 47 1 21 11 1 362 90 1 JO 12 1 100 25 1 11 13 1 484 121 1 54 1 Total 1 252 1 63 1 28 1 16 11 33 6 18 12 23 6 3() 9 Appendix F Read the entire page →
From page 202... ... , we again focus on this vehicle class in determining sample size. In this case, 18 sites are needed to detect a 20 percent change in Excess ESALs and a 20-30 percent change in average ESALs have to occur to conclude Mat enforcement was successful on rural interstates with truck volumes of 20-30 percent. Read the entire page →
From page 203... ... Table 11. Summary Statistics for Rural Interstates w~th Low % Truck Traffic \| KY3016 r MO1010 . Read the entire page →
From page 204... ... \| Percent Change to be Detected Vehicle Class \| 5 \| 10 \| 15 \| 20 5 1 34 8 1 4 6 1 324 81 1 36 7 1 516 129 1 57 8 1 107 26 1 12 9 1 288 72 1 32 10 1 208 52 1 23 11 1 291 73 1 32 12 1 91 23 1 10 13 1 253 63 1 28 Total 1 273 59 1 26 15 2 20 32 7 18 13 18 6 16 12 Appendix F Read the entire page →
From page 205... ... , we again focus on this vehicle class in determining sample size. In this case, 7 sites are needed to detect a 20 percent change in Excess ESALs and this wait be sufficient to detect as little as a 10 percent change in mean ESALs on rural ~nterstates with truck volumes of 40-60 percent. Read the entire page →
From page 206... ... Table 14. Summary Statistics for Rural Pr~mar~v Arterials with Low % Truck Traffic ~I FL 4109 1 \| Vehicle \| Total Ve- \| % Excess ~ Average \| TotalVe Class hiclesESALsESALshicles ; 5 ~9914 ~0.1111 ~0.0073 ~4492 6 ~181 ~36.464~4.531 ~437 7 ~72g.571 ~7.224 ~4 30112.957~1.5670~303 9 ~25710.506~1.523 ~152 10 ~1o.ooo ~O.958 ~8 11 ~14 ~1.8300 ~3 1 1 12 ~30.0000 ~0 13 ~0 ~I I All ~10678 ~1.376 ~.0172 ~5400 ~5.574 ~0.5524 FL 4138 % Excess ESALs Average ESALs 1.135 0.0540 33.638 3.471 100.00 13.524 23.762 2.930 15.789 1.700 25.000 2.2400 n non () Read the entire page →
From page 207... ... . \| Percent Change to be detected 1' Vehicle Class 5 10 15 ~20 5 1 9 1 2 T 1 r ~ 6 475 118 53 7 1 521 130 T 58 8 1 315 79 T 35 230 57 T 26 0 1 363 91 T 40 1 1 218 55 T 24 ~ 11 1 57 1 14 T 6 T 4 1 30 33 20 14 23 14 15 Appendix F Read the entire page →
From page 208... ... However, it would appear that a sample size of 30 sites are needed to detect a 20 percent change in Excess ESALs and a 40 percent change in average ESALs have to occur to conclude that enforcement was successful on rural primary arterials with truck volumes of 3 to 4 percent. This probably suggests that it is not practically feasible to attempt to evaluate M.O.E.'s on primary rural arterials at these low truck volumes. Read the entire page →
From page 209... ... Summary Statistics for Principal Arter~als with Medium % Truck Traffic 1 RI7401 1 KS 1006 Vehicle Total Ve- % Excess AverageTotal Ve-% Excess Class hicles ESALs ESALshiclesESALs 5 ~86928 7.228 ~0.3886450 ~3.008 18605 23.101 ~3.571822 ~3.041 ~1058 84.405 ~20.20314 ~14.286 8 ~60449 14.394 ~1.4601160 ~0.603 ~173950 26.668 ~6.2263666 ~4.255 10 ~1934 32.989 ~5.83540 ~2.500 11 ~981 15.494 ~2.18767 ~1.493 2 ~49 32.653 ~4.91529 ~0 13 ~22 50.000 ~10.63122 ~0 . , All ~343976 21.106 ~3.800 ~12270 ~3.146 0.396 Average ESALs 0.164 . Read the entire page →
From page 210... ... Table 18. Number of Sites Required to Detect 5-20 percent change in % Excess ESALs Percent Charlge to be detected 1 Vehicle Class \| 5 \| 10 \| 15 1 20 5 1 136 1 34 1 15 1 8 6 364 91 40 290 73 32 255 64 28 _ 434 109 48 . Read the entire page →
From page 211... ... , we again focus on this vehicle class in determining sample size. In this case, 27 sites would be required to detect a 20 percent change in Excess ESALs and a 50 percent change would be required to declare a significant reduction in average ESALs due to enforcement for rural primary arterials with 9-11 % Muck volume. Read the entire page →
From page 212... ... Table 20. Summary Statistics for Rural Principal Arterials with High % Truck Traffic 12433 7.36 my: Vehicle Total Ve- % Excess Average Class hicles ESALs ESALs 5 1408 1.207 0.1667 T460 5.2171 0.4463 . Read the entire page →
From page 213... ... l \| Percent Change to be detected l \| Vehicle Class \| 5 \| 10 \| 15 ~I 5 122 30 14 . Read the entire page →
From page 214... ... Percent Charge to be detected Vehicle 1 0 20 30 40 5 1 99 50 1 33 25 3 2 1 1 1 23 11 1 8 6 1 2 1 1 1 1 10 1 5 2 ~2 1 12 1 1 1 1 13 105 53 35 26 All 36 18 12 9 7 50 20 s 1 1 21 Since vehicle class 9 was dominant in both total frequency on rural primary arterials with high truck volume and frequency of violations (percent Excess ESAL`s) , we again focus on this vehicle class in determining sample size. Read the entire page →
From page 215... ... average ESALs. Table 22. Read the entire page →
From page 216... ... rig Vehicle Class 87 I 10 ~15 ~20 22 10 s 6 169 42 19 11 18 7 283 71 31 8 100 25 11 6 9 85 21 9 8 s 64 10 11 12 74 18 s 16 4 51 13 6 3 13 o o o o All 1 121 1 30 1 13 1 8 24 Appendix F Read the entire page →
From page 217... ... . I Percent Change to be detected Vehicle I 10 20 \| 30 40 \| Class l l l l 128 1 64 1 43 1 32 6 1 53 1 27 1 18 T 13 28 1 14 1 9 T 7 8 1 67 1 33 1 22 1 17 9 1 19 1 9 1 6 T 5 1 4 10 1 23 1 11 1 8 T 6 11 1 65 1 33 1 22 1 16 12 1 60 1 30 1 20 1 15 13 1 85 T 42 1 28 T 21 All 1 100 1 50 1 33 1 25 50 26 11 6 13 5 13 12 17 Sample size requirements are high for vehicle class 7 on percent Excess ESALs primarily due to rN 2009 Mat had 70% of We vehicle in this class as overweight. Read the entire page →
From page 218... ... Urban Interstates with Medium % Truck Volumes (MO 4036, AR 3059, and WA 3019) Table 26 lists summary statistics, table 27 lists sample sizes for the M.O.E. Read the entire page →
From page 219... ... . l Percent Change to be Detected , T Vehicle Class ~5 ~10 ~15 ~20 5 64 16 7 6 1 218 55 1 24 7 350 88 39 8 1 63 16 1 7 9 133 33 15 10 1 41 10 1 5 1 1 1 127 32 1 14 12 1 56 14 1 6 13 1 21 5 1 2 1 All 124 31 - 14 8 4 14 22 4 8 3 8 4 27 Appendix F Read the entire page →
From page 220... ... Since vehicle class 9 was dominant in both total frequency arid frequency of violations (percent Excess ESALs) on urban interstates with medium truck volume, this will be our focal point in sample size determination. Read the entire page →
From page 221... ... , table 301ists sample sizes for the M.O.E. percent Excess ESALs and table 31 lists these for the M;O.E. Read the entire page →
From page 222... ... I Percent Change to be Detected Vehicle Class \| 5 \| 10 \| 15 \| 20 . Read the entire page →
From page 223... ... , this will be our focal point in sample size deterrnination. In this case, 15 sites would allow a declaration of a 15 % reduction in Excess ESALs and a 10 percent reduction in average ESALs to be a statistically significant indicator of an effective enforcement program for urban interstate s and primary arterials with 13-28 percent truck volume. Read the entire page →
From page 224... ... Table 32. Summary Statistics for Urban Primary Arterials with Low % Truck Traffic 1 WA3813 1 WA6049 Vehicle ~ To~Ve- \| %Excess ~ Average \| TotalVe- ~ %Excess Class hicles ESALs ESALs \|hicles \| ESALs . Read the entire page →
From page 225... ... \| Percent Change to be Detected Vehicle Class \| 5 \| 10 \| 15 l 5 1 62 15 1 7 6 1 81 20 1 9 1 138 35 1 15 8 1 47 12 1 5 1 go 22 1 10 10 1 37 9 1 4 1 1 1 91 23 1 10 12 1 58 13 1 6 13 1 53 13 1 6 All 1 71 1 18 1 8 1 4 20 4 s 9 3 6 3 6 3 3 33 Appendix F Read the entire page →
From page 226... ... on urban primary arterials troth low truck volume were vehicle class 9 and 5, respectively. Examining the sample size requirements for these classes, 15 sites would allow a declaration of a 15 % reduction in Excess ESALs and a 40 percent reduction in average ESALs to be a statistically significant indicator of an effective enforcement program. Read the entire page →
From page 227... ... , table 35 lists sample sizes for the M.O.E. percent Excess ESALs and Table 37 lists these for the M.O.E. Read the entire page →
From page 228... ... ~Percent Change to be Detected \| Vehicle Class 5 10 15 5 30 7 3 6 53 13 6 7 1 85 21 1 9 8 1 27 7 1 3 1 47 12 1 5 10 1 21 1 2 11 1 61 15 1 7 12 1 34 9 1 4 13 1 23 6 1 3 All 1 38 9 1 4 2 20 2 3 1 4 2 1 36 Appendix F Read the entire page →
From page 229... ... Examining the sample size requirements for these classes, 9 sites would allow a declaration of a 10-15 % reduction in Excess ESALs and a 40 percent reduction in average ESALs to be a statistically significant indicator of an effective enforcement program. If we were only interested in the M.O.E. Read the entire page →
From page 230... ... Detecting changes in percent Excess ESALs generally requires more samples than detecting a percentage change in Excess ESALs. That is, if we are most interested in declaring a ~ 5 percent reduction in the percent of Vehicle Class 9 trucks with Excess ESALs after enforcement, this requires more sites than if we want to be able to say that the reduction in average ESALs was ~ 5% less than the average ESALs before enforcement. Read the entire page →
From page 231... ... Functional Class Low Medium Rural Interstates 2 ~ 5 Rural Principal Arte- 2 4 reals Rural Minor Arteriole 6 Urban Interstate s 12 Urban Principal Arte nals . Urban Interstates and 5 4 Pr~ncipla Arter~als Combined Total 1 5 60 High 2 2 4 SITE NUMBER REQUIREMENTS FOR OVERWEIGHT VIOLATIONS Given the foregoing detailed development of ESAL and Excess ESAL sampling reqliirements, a more streamlined approach was applied with regard to the remaining M.O.E.s, i.e., Proportion of trucks with Gross Weight Violations' Proportion with Tandem Violations' arid Proportion with Single Axle Violations. Read the entire page →
From page 232... ... Site Number Requirements for Gross Truck Weight Violations 11 PERCENT CHANGE TO BE DETECTED FUNCTIONAL CLASS 10 ~20 l 30 ~50 Rural Interstate < 15 % Trucks 40 10 15 to 30 %; 24 Trucks > 30% Trucks 48 12 Rural Primal Arterial < 9 TO Trucks 40 1 0 9 to 30 % Trucks 105 26 . > 30�/O Trucks 20 5 Rural Minor Arterial 44 1 1 Urban Interstate < 9% Trucks 5 1 > 9% Trucks 25 6 Urban Primary Arterial < 9% Trucks 32 ~ > 9�/O Trucks ~ ~ 49 ~12 2 4 s 2 2 2 4 2 . Read the entire page →
From page 233... ... Proportion of Trucks with Single Axle Weight Violations: Table 42 on We next page indicates the required site numbers to detect changes in the proportion of trucks exhibiting at least one overweight axle which exceeds We legal weight Innit, given the specified detection level thresholds. 41 Appendix F Read the entire page →
From page 234... ... Table 42. Site Number Requirements for Single-AxIe Violations PERCENT CHANGE TO BE DETECTED FUNCTIONAL CLASS 10 _\| 30 40 Rural nte ate <15%Trucks 1 33 ~4 LO is to 30 % Trucks 84 81_ 5 > 30% Trucks 50 _ 6 - 3 Rural Primary Arterial ~ < 9 % Trucks 45 Em_ 5 3 9 to 30 % Trucks 98 ~ ~6 > 30% Trucks 20 ~j 2 1 Rural Minor Arterial 36 ~4 2 Urban Interstate < 9% Trucks 7 > 9% Trucks 24 ~3 Urban Prima Ar erial < 9% Trucks 1 28 ~3 LO > 9% Trucks 3 ~3 2 5(} 2 3 . Read the entire page →

From page 193...

... The selection process designated Me 22 sites noted above, resuming In a highway functional class distribution as follows: 6 Rural Interstates, 6 Rural Pnncipal Arterials, 3 Rural Minor Arterials, 4 Urban Interstates, and 3 Urban Primary Arterials . The resulting distribution by region is as follows: ~ Central, 5 West, 4 Atlantic, 5 South.

APPENDIX F M.O.E. Sampling Plan Development Pages 193-234

APPENDIX F M.O.E. Sampling Plan Development
Pages 193-234