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Chapter 3: The Tool 21 Specific Weight refers to the weights entered in Rows 9 to 69 of Worksheet 1, Evaluation Weights. These weights are for specific criteria listed within each evaluation group. For exam- ple, in the Security Objective group, specific criteria are deter, detect, deny, and mitigate. 3.9.2 Calculation of Weight-Adjusted Ranks The general method for calculation of weight-adjusted ranks is to multiply rank by weight. The (rank)(weight) is expressed as a fraction of the maximum possible rank and average group or sub- group weight and then multiplied by the total possible utils for the specific criteria (i.e., the maxi- mum group or sub-group utils divided by the number of specific criteria in the group or sub-group). Maximum Group Utils are shown in Row 7 (Cells V7, AA7, AF7, and AL7) and Row 5 (Cell BG5) of the Hidden Calculations worksheet. The Excel equations for these cells are shown in Table 2. Maximum group utils are calculated as the product of the total utils (i.e., 100) and the fraction of the group weight divided by the summation of all group weights. Thus, when all group weights are equal, there are 20 possible utils for each group. When all group weights are not equal (the more common case), some groups will have maximum possible utils above 20, and others below 20. Maximum Threat Type Sub-Group Utils are shown in Cells AZ7, BH6, and BK7. The Excel equations for these cells are shown in Table 2. The three sub-groups within the Threat Type group Table 2. Equations for calculations of maximum possible utils. Cell Excel Equation Explanation V7 =('1. Evaluation Weights'!$H$75/SUM('1. Maximum possible utils for the Group, Security Evaluation Weights'!$H$75:$H$79))*100 Objectives, given the weights provided on Sheet 1, Evaluation Weights. AA7 =('1. Evaluation Weights'!$H$76/SUM('1. Maximum possible utils for the Group, Non-Security Evaluation Weights'!$H$75:$H$79))*100 Effects, given the weights provided on Sheet 1, Evaluation Weights. AF7 =('1. Evaluation Weights'!$H$77/SUM('1. Maximum possible utils for the Group, 33 CFR Evaluation Weights'!$H$75:$H$79))*100 Compliance, given the weights provided on Sheet 1, Evaluation Weights. AL7 =('1. Evaluation Weights'!$H$78/SUM('1. Maximum possible utils for the Group, Security Locations, Evaluation Weights'!$H$75:$H$79))*100 given the weights provided on Sheet 1, Evaluation Weights. BG5 =('1. Evaluation Weights'!$H$79/SUM('1. Maximum possible utils for the Group, Threat Type, given Evaluation Weights'!$H$75:$H$79))*100 the weights provided on Sheet 1, Evaluation Weights. AZ7 =(AVERAGE(AX10:BC10))/(AVERAGE( Maximum possible utils for the Threat Type sub-group, AVERAGE($AX$10:$BC$10),AVERAGE Deliver Explosive/Incendiary, given the weights provided. ($BD$10:$BH$10),AVERAGE($BI$10:$ BK$10)))*($BG$5/3) BH6 =(AVERAGE(BD10:BH10))/(AVERAGE( Maximum possible utils for the Threat Type sub-group, AVERAGE($AX$10:$BC$10),AVERAGE Act of Force, given the weights provided. ($BD$10:$BH$10),AVERAGE($BI$10:$ BK$10)))*($BG$5/3) BK7 =(AVERAGE(BI10:BK10))/(AVERAGE(A Maximum possible utils for the Threat Type sub-group, VERAGE($AX$10:$BC$10),AVERAGE( WMD Delivery, given the weights provided. $BD$10:$BH$10),AVERAGE($BI$10:$B K$10)))*($BG$5/3)

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22 Part I: Guide for Evaluating Security Measures for the U.S. Ferry System Table 3. Equations for weight-adjusted ranks (i.e., util valuations). Column Group Excel Equation (in upper right cell) Explanation V Security =(('4. Applicability Ranks'!F11*V$10)/ For each GSM (row) and each specific criterion Objective ((AVERAGE($V$10:$Y$10))*3)) (column) GSM rank is: *($V$7/4) Y 1. Multiplied by the specific weight, AA Non-Security =(('4. Applicability Ranks'!K11*AA$11)/ 2. Expressed as a fraction of the average Effects ((SUM($AA11:$AD11)/4)*3))* specific weight and maximum rank, ($AA$8/4) 3. Multiplied by the maximum group utils divided AD by the number of criteria in the group. AF 33 CFR =(('4. Applicability Ranks'!P11*AF$11)/ Compliance ((SUM($AF11:$AJ11)/5)*3))* ($AF$8/5) AJ AL Locations =(('4. Applicability Ranks'!V11*AL$11)/ ((SUM($AL11:$AV11)/11)*3))* ($AL$8/11) AV AX Threat Type =(('4. Applicability Ranks'!AH11*AX$11)/ For each GSM (row) and each specific criterion EID Sub- ((SUM($AX11:$BC11)/6)*3))* (column) GSM rank is: group (($AX$8/3)/6) BC 1. Multiplied by the specific weight, BD Threat Type =(('4. Applicability Ranks'!AN11*BD$11)/ 2. Expressed as a fraction of the average Act of ((SUM($BD11:$BH11)/5)*3))* specific weight and maximum rank, Force Sub- (($AX$8/3)/5) 3. Multiplied by the maximum sub-group utils BH group divided by the number of criteria in the sub- BI Threat Type =(('4. Applicability Ranks'!AS11*BI$11)/ group. BJ WMD Sub- ((SUM($BI11:$BK11)/3)*3))* BK group (($AX$8/3)/3) (i.e., Delivery of Explosives/Incendiaries, Acts of Force, and WMD Delivery) are allotted portions of the maximum group utils (show in Cell BG5) based on the sub-group's average weight. More specifically, the maximum group utils is divided by 3 (i.e., the number of sub-groups), and multi- plied by the fraction of the sub-group average weight divided by the average of the average sub- group weights for all three sub-groups. Thus, sub-groups are weighted according to their average sub-group weight and are not affected by varied numbers of specific criteria within each sub-group. Rows 11 and higher (Columns V through BK) display weight-adjusted ranks for each GSM and specific evaluation criteria. Sample equations in these columns are shown in Table 3. There are three parts to the equation for weight-adjusted ranks: 1. Apply the specific weight to the rank--that is, (Rank)(Specific Weight). 2. Express (Rank)(Specific Weight) as a fraction of the maximum rank and the average specific weight. This makes it so specific weights are relative within their group--if all specific weights in a group are the same, it makes no difference if the specific weights are all reported as 1 or 5. 3. Multiply the above fraction by the maximum possible utils for the specific criteria. This is the maximum possible utils for the group (as in Row 7) given the evaluation weights provided, divided by the number of specific criteria within the group (e.g., 4 in the Security Objective group). For the Threat Type group, the maximum possible utils for the sub-group is used in place of the group maximum utils.