This table presents the cost-benefit ratios of four levels of interventions/targets to achieve improved access to water supply and sanitation for seven different regions of the world. For example, the total global economic benefits for reaching the MDG target accrue to $84 billion.

2a. Explain how the cost-benefit ratio differs from the cost effectiveness ratio and why the costbenefit ratio is more appropriate here than the cost-effectiveness ratio. (5 points)

2b. State numerically (and show calculations) for how the cost-benefit ratio for intervention 4 Access for all to regulated in-house piped water - for Africa is calculated (Hint: all the information you need is in the table). (4 points)

2c. State two types of benefits and two types of costs that the researchers would have included in their analysis. (4 points)

2d. Suppose all the benefits were calculated using outcomes from RCTs. These RCTs were all testing one package of interventions: the provision of small scale water supply technologies; and hygiene awareness and promotion. Based on the table below, do you think that the result that this package of interventions improved access to water supply and sanitation is generalizable? Why or why not? (4 points)

Cost-benefit ratios and, Total economic benefits by intervention Halving the proportion of people Access for all to improved water and Access for all to improved water and Access for all to regulated in house Region without access to both improved improved sanitation services sanitation services plus household piped water an sewerage connection water supply and improved sanitation water treatment at point of use Meeting the MDG Torget Select counCost/Ben Annud Annual Cost/Ben- Annual Annud Cost/Ben Annual Annud Cost/Ben Annual Annual tries within: efit Costs in Benefits in sfit Costs in Benefits inefit Costs in Benefits inefit Cost in Benefits in USD millions USD millions USD millions USD millions USD millions USD millions USD millions USD millions Africa 11.33 2021 2290B 10.89 4043 44036 14.269 4360 62214 4.39 24729 108441 America 10.21 157 1607 10.59 315 3334 13.77 368 5074 3.88 2320 9007 Europe 3,40 71 242 6.55 143 934 5.82 266 1551 1.27 4206 5337 E. Mediter- 34.95 100 3505 42.50 201 8523 61.47 153 55 14.49 3273 47431 ranean South East 3.16 3628 11457 7.88 7257 57155 9.41 7704 72478 2.90 35074 101643 Asia Western 3.36 3282 11013 6.63 6563 43487 7.89 6957 54885 1.93 28129 54426 Pacific Rest of the 2046 33668 4087 105410 4744 132549 38782 229616 world Total 7.50 11305 84400 11.63 22609 282879 13.96 24649 344106 4.07 136515 555901 250 Making Water a part of Economic Development Table 42 Cosebenaltratos and told economic benefits for four homentos - all costs and all benefits induced Note: The countries included in each region are those with the highest adult and child mortality rates, A complete listing of each of the countries that are included in each of these categories is provided in Hutton & Haller (2004). The region "Africa" includes both category E and category African countries as identified by Hutton & Haller (2004). Cost-benefit ratios and, Total economic benefits by intervention Halving the proportion of people Access for all to improved water and Access for all to improved water and Access for all to regulated in house Region without access to both improved improved sanitation services sanitation services plus household piped water an sewerage connection water supply and improved sanitation water treatment at point of use Meeting the MDG Torget Select counCost/Ben Annud Annual Cost/Ben- Annual Annud Cost/Ben Annual Annud Cost/Ben Annual Annual tries within: efit Costs in Benefits in sfit Costs in Benefits inefit Costs in Benefits inefit Cost in Benefits in USD millions USD millions USD millions USD millions USD millions USD millions USD millions USD millions Africa 11.33 2021 2290B 10.89 4043 44036 14.269 4360 62214 4.39 24729 108441 America 10.21 157 1607 10.59 315 3334 13.77 368 5074 3.88 2320 9007 Europe 3,40 71 242 6.55 143 934 5.82 266 1551 1.27 4206 5337 E. Mediter- 34.95 100 3505 42.50 201 8523 61.47 153 55 14.49 3273 47431 ranean South East 3.16 3628 11457 7.88 7257 57155 9.41 7704 72478 2.90 35074 101643 Asia Western 3.36 3282 11013 6.63 6563 43487 7.89 6957 54885 1.93 28129 54426 Pacific Rest of the 2046 33668 4087 105410 4744 132549 38782 229616 world Total 7.50 11305 84400 11.63 22609 282879 13.96 24649 344106 4.07 136515 555901 250 Making Water a part of Economic Development Table 42 Cosebenaltratos and told economic benefits for four homentos - all costs and all benefits induced Note: The countries included in each region are those with the highest adult and child mortality rates, A complete listing of each of the countries that are included in each of these categories is provided in Hutton & Haller (2004). The region "Africa" includes both category E and category African countries as identified by Hutton & Haller (2004)