Schedule • Homeworks: – Homework 3, due to 23-March-2009 17:00 – Homework 4, due to 30-March-2009 17:00 • Reading homework – Golf (golfers by fried-lambrinos-tyler in EJOR04.pdf): Next Tuesday (17-03-09) due to class time. – Oral and Yolalan (oralyolalan.pdf): due to class time on Thursday, 19-03-09. – Modell’s DEA (modell.pdf): due to class time on Thursday, 19-03-09. Obtain file(s): • Copy and paste the excel file to your own accounts: F:\COURSES\UGRADS\INDR\INDR471\SHARE\Labs\lab3-DLP-A-so.xls • Also open the power point file: F:\COURSES\UGRADS\INDR\INDR471\SHARE\labs\DEA-Lab-12-03-09.ppt Example: Data Store Employee Area Sales Profits A 10 20 70 6 B 15 15 100 3 C 20 30 80 5 D 25 15 100 2 E 12 9 90 8 Example: Results for A Efficiency of A: qA =0.93333 Reference set: RA={ lambda E } Employee (n1, s1-) Area (n2, s2-) Sales (u1, s1+) Profits (u2 , s2+) Optimal weights 0.1 0 0.013333 0 Slacks 0 11.66667 0 0.2222 Slacks DLP II-da formullerin icinde, optimal weights DLP I sensitivity shadow prices. 3.a. Discuss the meaning of u1 of A, and its effect on the efficiency of A. How about u2 of A? Compute the efficiency of A if the corresponding output is increased by one unit. How can you interpret the relation between the weights u1 and u2 of A, and the corresponding slacks, s1+ and s2+, using the complementary slackness condition? – if you increse the outputs by one the efficiency increses by the weights. Complementary slackness=S(i)*u(i) 3.b. Discuss the meaning of n1 of A, and its effect on the efficiency of A. Note that a change in the employee input, n1, changes the constraint (unlike a change in the outputs). N v I i 1 i ie 1 Compute the efficiency of A if the Number of employees is decreased by one unit. – if you increse the inputs by epsilone E(new)=E(old)/(1v(i)*epsilone) Now: Make sure that in Excel: • Tools*Macro*Security: – Security Level “Medium” should be changed to “Low” • Tools*Options*International: – Decimal separators “ . ” – Thousands separator “ , ” The easy way … DEA solver • Copy the files into your own accounts: – F:\COURSES\UGRADS\INDR\INDR471\SHARE\labs\LAB3-Ex1DEAsolver-data.xls, – F:\COURSES\UGRADS\INDR\INDR471\SHARE\labs\LAB3-Ex2DEAsolver-data.xls – F:\COURSES\UGRADS\INDR\INDR471\SHARE\software helps\DEASolver-LV.xls. – F:\COURSES\UGRADS\INDR\INDR471\SHARE\reading material\DEA SOLVER USER MANUAL.doc. • Open the file “DEA-Solver-LV.xls” • Click here to start OK CCR-I OK OK Choose Ex1DEAsolver-data.xls Run Save as Ex1-DEAsolver-CCR-I.xls -Example 1DEA Solver output: Weights Model Name = CCR-I Workbook Name = D:\DEA\LAB2-PART1-results.xls No. DMU Score V( 1) V( 2) 1A 0.857143 0.1429 0.1429 2B 0.631579 0.0526 0.2105 3C 1 0.0833 0.3333 4D 1 0.1667 0.1667 5E 1 0.2143 0.1429 6F 1 0.0000 1.0000 7G 0.666667 0.3333 0.0000 U( 1) 0.8571 0.6316 1.0000 1.0000 1.0000 1.0000 0.6667 DEA Solver output for Example 1 Model Name = CCR-I Workbook Name = D:\DEA\LAB2-PART1-results.xls Excess Excess Shortage No. DMU Score Input 1 Input 2 Output S-( 1) S-( 2) S+( 1) 1A 0.857143 0 0 0 2B 0.631579 0 0 0 3C 1 0 0 0 4D 1 0 0 0 5E 1 0 0 0 6F 1 2 0 0 7G 0.666667 0 0.666667 0 DEA solver • Open the file “DEA-Solver-LV.xls” • Click here to start OK CCR-O OK OK Choose Ex1-DEAsolver-data.xls Run Save as Ex1-DEAsolver-CCR-O.xls Questions - 1 • What are the efficiencies of the DMUs? Which DMUs have purely technical (or ratio) inefficiencies? • Relation between CCR-I (q*,v*,u*) and CCR-O (h *,p*,q*) ? – h* =1/ q* – m*= l*/q* – t-*=s-*/ q* , t+*=s+*/ q* – p* =v*/ q* , q* =u*/q* Questions - 2 • What are the values of the slack variables for each of the DMUs? Identify the DMUs as efficient, ratio inefficient, mix inefficient and both ratio and mix inefficient. • Relation between CCR-I (q*, v*, u*) and CCR-O (h*, p*, q*) ? – h* =1/ q* – m*= l*/q* – t-*=s-*/ q* , t+*=s+*/ q* – p* =v*/ q* , q* =u*/q* Questions - 3 • What are the values of lk’s? What are the level of inputs for each DMU to be efficient in CCR-I? • What are the values of mk’s? What are the level of outputs for each DMU to be efficient in CCR-O? • Relation between CCR-I (q*, v*, u*) and CCR-O (h*, p*, q*) ? – h* =1/ q* – m*= l*/q* – t-*=s-*/ q* , t+*=s+*/ q* – p* =v*/ q* , q* =u*/q* DEA solver • Open the file “DEA-Solver-LV.xls” • Click here to start OK BCC-I OK OK Choose Ex1-DEAsolver-data.xls Run Save as Ex1-DEAsolver- BCC-I.xls DEA solver • Open the file “DEA-Solver-LV.xls” • Click here to start OK BCC-O OK OK Choose Ex1-DEAsolver-data.xls Run Save as Ex1-DEAsolver- BCC-O.xls Questions - 1 • What are the efficiencies of the DMUs? Which DMUs have purely technical (or ratio) inefficiencies? Questions - 2 • What are the values of the slack variables for each of the DMUs? Identify the DMUs as efficient, ratio inefficient, mix inefficient and both ratio and mix inefficient. Questions - 3 • What are the values of lk’s? What are the level of inputs for each DMU to be efficient in BCC-I? • What are the values of mk’s? What are the level of outputs for each DMU to be efficient in BCC-O? Questions - 4 • What are the returns-to-scale (RTS) of DMUS in BCC-I and in BCC-O? DEA Solver for Example 2… • For CCR-I, CCR-O, BCC-I, BCC-O … • Let’s answer the above questions for this one as well…