Comparing farmers’ willingness to pay with costs of clean sweet potato seed multiplication in Kenya

Abidin, P. E., Dery, E., Amagloh, F. K., Asare, K., Amoaful, E. F., & Carey, E. E. (2015). Training of Trainers’ Module for Orange-Fleshed Sweetpotato (OFSP). Utilization and Processing. In Training of Trainers’ Module for Orange-Fleshed Sweetpotato (OFSP). Utilization and Processing. https://doi.org/10.4160/9789290604624 Ainembabazi, J. H., & Mugisha, J. (2014). The Role of Farming Experience on the Adoption of Agricultural Technologies: Evidence from Smallholder Farmers in Uganda. Journal of Development Studies, 50(5), 666–679. https://doi.org/10.1080/00220388.2013.874556 Almekinders, C. J. M., Walsh, S., Jacobsen, K. S., Andrade-piedra, J. L., Mcewan, M. A., Haan, S. D., Kumar, L., & Staver, C. (2019). Why interventions in the seed systems of roots, tubers and bananas crops do not reach their full potential. Food Security, 11, 23–42. https://doi.org/10.1007/s12571-018-0874-4 Aremu, P. A., Kolo, I. N., Gana, A. K., & Adelere, F. A. (2015). The Crucial Role of Extension Workers In Agricultural Technologies Transfer and Adoption. Global Advanced Research Journal of Food Science and Technology, 4(2), 14–18. Ateka, J. M., Mbeche, R., Obebo, F., & Sila, D. (2021). Preferences and Willingness to Pay for Yogurt Product Attributes Among Urban Consumers in Kenya. Journal of International Food and Agribusiness Marketing, 0(0), 1–22. https://doi.org/10.1080/08974438.2021.1902449 Ayedun, B., Okpachu, G., Manyong, V., Atehnkeng, J., Akinola, A., Abu, G. A., Bandyopadhyay, R., & Abdoulaye, T. (2017). An Assessment of Willingness to Pay by Maize and Groundnut Farmers for Aflatoxin Biocontrol Product in Northern Nigeria., 80(9), 1451–1460. https://doi.org/10.4315/0362-028X.JFP-16-281 Bain, L. E., Awah, P. K., Geraldine, N., Kindong, N. P., Sigal, Y., Bernard, N., & Tanjeko, A. T. (2013). Malnutrition in Sub - Saharan Africa: Burden, causes and prospects. Pan African Medical Journal, 15, 1–9. https://doi.org/10.11604/pamj.2013.15.120.2535 Bartle, B. (2019). The Effect of Quality Signaling and Trust on Willingness to Pay for Potato Planting Material: A Research Study in Kenya. 1–70. Becker, G. M., DeGroot, M. H., & Marschak, J. (1964). Measuring utility by a single-response sequential method. Behavioral Science, 9(3), 226–232. https://doi.org/10.1002/BS.3830090304 Berkowsky, R. W., Sharit, J., & Czaja, S. J. (2018). Factors Predicting Decisions About Technology Adoption Among Older Adults. Innovation in Aging, 1(3), 1–12. https://doi.org/10.1093/geroni/igy002 Bhattarai, K. (2019). Consumers’ willingness to pay for organic vegetables: empirical evidence from Nepal. Economics and Sociology, 12(3), 132–146. https://doi.org/10.14254/2071-789X.2019/12-3/9 Brebner, S., & Sonnemans, J. (2018). Does the elicitation method impact the WTA/WTP disparity? Journal of Behavioral and Experimental Economics, 73, 40–45. https://doi.org/10.1016/j.socec.2018.01.006 Breidert, C., Hahsler, M., & Reutterer, T. (2006). A review of methods for measuring willingness to pay. Innovative Marketing, 2(4), 8–32. Cameron, T. A., & James, M. D. (1987). Efficient Estimation Methods for " Closed-Ended " Contingent Valuation Surveys Author ( s ): Trudy Ann Cameron and Michelle D . James Source : The Review of Economics and Statistics , Vol . 69 , No . 2 ( May , 1987 ), pp . 269–276 Published by : The MIT P. The Review of Economics and Statistics, 69(2), 269–276. http://www.jstor.org/stable/1927234 Chelang’a, P. K., Obare, G. A., & Kimenju, S. C. (2013). Analysis of urban consumers’ willingness to pay a premium for African Leafy Vegetables (ALVs) in Kenya: A case of Eldoret Town. Food Security, 5(4), 591–595. https://doi.org/10.1007/s12571-013-0273-9 Chia, S. Y., Macharia, J., Diiro, G. M., Kassie, M., Ekesi, S., Van Loon, J. J. A., Id, M. D., & Id, C. M. T. (2020). Smallholder farmers ’ knowledge and willingness to pay for insect-based feeds in Kenya. PLoS ONE, 15(3), 1–25. https://doi.org/10.1371/journal.pone.0230552 CIP. (2018). Everything you ever wanted to know about sweetpotato. Topic 5 ‐ Sweetpotato Seed Systems. In Everything you ever wanted to know about sweetpotato. Topic 5: Sweetpotato seed systems. Reaching agents of change ToT manual. (Issue October). https://doi.org/10.4160/9789290605027t5 Cranfield, J. (2018). Will Consumers Pay for Voluntary Testing for BSE? Double-Bound CVM Evidence from Canada. Journal of Food Products Marketing, 24(6), 697–723. https://doi.org/10.1080/10454446.2017.1329676 Etten, van J., Noriega, I. L., Fadda, C., & Thomas, E. (2017). The contribution of seed systems to crop and tree diversity in sustainable food systems. Mainstreaming Agrobiodiversity in Sustainable Food Systems, 81–102. FAO. (2016). Agricultural Cost of Production Statistics. Guidelines for Data Collection , Compilation and Dissemination. FAO. (2019). Africa regional overview of food security and nutrition. FAO, & ECA. (2018). Regional Africa Overview of Food Security and Nutrition. Addressing the threat from climate variability and extremes for food security and nutrition. In Addressing the threat from climate variability and extremes for food and security and nutrition.Accra. https://doi.org/10.1016/j.meatsci.2013.04.036 FAO, IFAD, UNICEF, WFP, & WHO. (2018). The State of Food Security and Nutrition in the World 2018. Building climate resilience for food security and nutrition. In World Nutrition (Vol. 10, Issue 3). FAO. https://doi.org/10.26596/wn.201910395-97 Florio, M., & Giffoni, F. (2020). A contingent valuation experiment about future particle accelerators at CERN. PLOS ONE, 15(3), e0229885. https://doi.org/10.1371/JOURNAL.PONE.0229885 Fuglie, K. O., Adiyoga, W., Asmunati, R., Mahalaya, S., & Suherman, R. (2006). Farm demand for quality potato seed in Indonesia. Agricultural Economics, 35(3), 257–266. https://doi.org/10.1111/j.1574-0862.2006.00160.x Genius, M., Koundouri, P., Nauges, C., & Tzouvelekas, V. (2014). Information transmission in irrigation technology adoption and diffusion: Social learning, extension services, and spatial effects. American Journal of Agricultural Economics, 96(1), 328–344. https://doi.org/10.1093/ajae/aat054 Hanemann, M., Loomis, J., & Kanninen, B. (1991). Statistical Efficiency of Double-Bounded Dichotomous Choice Contingent Valuation. American Journal of Agricultural Economics, 73(4), 1255–1263. https://doi.org/10.2307/1242453 HarvestPlus. (2019). Sweetpotato seed systems: A farmers trainers’ guide. In The Potato Crop: Its Agricultural, Nutritional and Social Contribution to Humankind. https://doi.org/10.1007/978-3-030-28683-5_12 Hoyos, D., & Mariel, P. (2010). Contingent valuation: Past, present and future. Prague Economic Papers, 4, 329–343. https://doi.org/10.18267/j.pep.380 International Potato Centre. (2019). What motivates vine multipliers to continue once project support has ended ? A Case Study from the Lake Zone , Tanzania. IPCC. (2019). Climate change and land: An IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems. In Research Handbook on Climate Change and Agricultural Law. https://doi.org/10.4337/9781784710644 Jepkemboi, C., Kebeney, S. J., & Kitilit, J. (2016). Factors affecting sweetpotato production and soil fertility challenges among smallholder farmers in Kenya. RUFORUM Working Document Series (ISSN 1607–9345), 14(2), 695–705. Jin, J., He, R., Gong, H., Xu, X., & He, C. (2017). Farmers ’ Risk Preferences in Rural China : Measurements and Determinants. International Journal of Environmental Research and Public Health, 14(713), 1–11. https://doi.org/10.3390/ijerph14070713 Johnston, R. J., Boyle, K. J., Vic Adamowicz, W., Bennett, J., Brouwer, R., Ann Cameron, T., Michael Hanemann, W., Hanley, N., Ryan, M., Scarpa, R., Tourangeau, R., & Vossler, C. A. (2017). Contemporary Guidance for Stated Preference Studies. Journal of the Association of Environmental and Resource Economists, 4(2), 319–405. https://doi.org/10.1086/691697 Kagimbo, F., Shimelis, H., & Sibiya, J. (2018). Sweet Potato Weevil Damage, Production Constraints, and Variety Preferences in Western Tanzania: Farmers’ Perception. Journal of Crop Improvement, 32(1), 107–123. https://doi.org/10.1080/15427528.2017.1400485 Kaguongo, W., Maingi, G., Barker, I., & Nganga, N. (2013). The Value of Seed Potatoes from Four Systems in Kenya. American Journal of Potato Research. https://doi.org/10.1007/s12230-013-9342-z Kassie, G. T., Abdulai, A., Greene, W. H., Shiferaw, B., Abate, T., Tarekegne, A., & Sutcliffe, C. (2017). Modeling Preference and Willingness to Pay for Drought Tolerance ( DT ) in Maize in Rural Zimbabwe. World Development, 94, 465–477. https://doi.org/10.1016/j.worlddev.2017.02.008 Katungi, E., Karanja, D., Wozemba, D., Mutuoki, T., & Rubyogo, J. C. (2011). A cost benefit analysis of farmer based seed production for common bean in Kenya. African Crop Science Journal, 19(4), 409–415. Kenya National Bureau of Statistics. (2019). Kenya population and housing census volume 1: Population by County and sub-County. In Kenya National Bureau of Statistics: Vol. I (Issue November). https://www.knbs.or.ke/?wpdmpro=2019-kenya-population-and-housingcensus-volume-i-population-by-county-and-sub-county Khainga, D. N., Obare, G., & Nyangena, J. (2018). Estimating pastoralists willingness to pay for artificial insemination in arid and semi-arid lands of Kenya. Journal of Development and Agricultural Economics, 10(8), 262–270. https://doi.org/10.5897/jdae2018.0920 Kibet, N., Lagat, J., & Obare, G. (2011). Identifying Efficient and Profitable Farm Enterprises in Uasin-Gishu County, in Kenya. Asian Journal of Agricultural Sciences, 3(5), 378–384. http://www.maxwellsci.com/print/ajas/v3-378-384.pdf Kikulwe, E. M., & Asindu, M. (2020). A contingent valuation analysis for assessing the market for genetically modified planting materials among banana producing households in Uganda. GM Crops & Food, 11(2), 113–124. https://doi.org/10.1080/21645698.2020.1720498 Kiprop, J. K., Lagat, J. K., Mshenga, P., & Macharia, A. M. (2015). Determining the Economic Value of Irrigation Water in Kerio Valley Basin (Kenya) by Residual Value Method. Journal of Economics and Sustainable Development, 6(7), 102–108. Labarta, R. A. (2009). Are small Sub-Sahara African farmers willing to pay for vegetative propagated orange fleshed sweetpotato planting material? Evidence from Central Mozambique. Selected Paper Prepared for Presentation at the Agricultural & Applied Economics Association 2009 AAEA & ACCI Joint Annual Meetings, Milwaukee, Wisconsin, July 26–29 2009. Copyright. https://ageconsearch.umn.edu/record/49447/ Lieblein, G., Breland, T. A., Salomonsson, L., Bvsc, N. S., Francis, C. A., Sriskandarajah, N., & Francis, C. A. (2008). Educating Tomorrow ’ s Agents of Change for Sustainable Food Systems : Nordic Agroecology MSc Program Educating Tomorrow ’ s Agents of Change for Sustainable Food Systems : Nordic Agroecology MSc Program. Journal of Hunger and Environmental Nutrition, 0248.https://doi.org/10.1080/19320240802244355 Lopez-Feldman, A. (2012). Introduction to contingent valuation using Stata. MPRA Paper, 41018, 16. http://mpra.ub.uni-muenchen.de/41018/ Lusk, J. L., & Hudson, D. (2004). Willingness-to-pay estimates and their relevance to agribusiness decision making. Review of Agricultural Economics, 26(2), 152–169. https://doi.org/10.1111/j.1467-9353.2004.00168.x Mabhaudhi, T., Grace, V., Chimonyo, P., Hlahla, S., Massawe, F., Mayes, S., Nhamo, L., & Modi, A. T. (2019). Prospects of orphan crops in climate change. Planta, 1–14. https://doi.org/10.1007/s00425-019-03129-y Makini, F. W., Mose, L. O., Kamau, G. K., Salasya, B., Mulinge, W. W., Ongala, J., Makelo, M. N., & Fatunbi, A. O. (2018). Innovation Opportunities in Sweet Potato production in Kenya. Forum for Agricultural Research in Africa (FARA), Accra. https://faraafrica.org/wp-content/uploads/2018/02/Innovation-Opportunities-in-Sweet-Potato-Production-in-Kenya.pdf Maredia, M., Shupp, R., Opoku, E., Mishili, F., Reyes, B., Kusolwa, P., Kusi, F., & Kudra, A. (2019). Farmer perception and valuation of seed quality: Evidence from bean and cowpea seed auctions in Tanzania and Ghana. Agricultural Economics, 5(4), 495–507. Mastenbroek, A., Sirutyte, I., & Sparrow, R. (2020). Information Barriers to Adoption of Agricultural Technologies : Willingness to Pay for Certified Seed of an Open Pollinated Maize Variety in Northern Uganda. Journal of Agricultural Economics. https://doi.org/10.1111/1477-9552.12395 Mcfadden, D. (1999). To pay in random utility models. Trade, Theory, and Econometrics: Essays in Honour of John S. Chipman, 15(253), 1–29. Migwi, B., Mutegi, C., Mburu, J., Wagacha, J., Cotty, P., Bandyopadhyay, R., Manyong, V. M., Migwi, B., Mutegi, C., Mburu, J., Wagacha, J., & Cotty, P. (2020). Food Additives & Contaminants : Part A Assessment of willingness-to-pay for Aflasafe KE01, a native biological control product for aflatoxin management in Kenya. Food Additives & Contaminants: Part A, 37(11), 1951–1962. https://doi.org/10.1080/19440049.2020.1817571 Momanyi, V. N., Amata, R., & Atuncha, H. (2016). A Baseline Survey on Enhancing Sweet potato Production through Development and Promotion of Appropriate Weed Management and Spacing Technologies in Kenya. International Journal of Scientific and Research Publications, 6(1), 656–663. Mwangi, C. W., Ateka, J., Mbeche, R., & Ateka, E. (2020). Seed security for vegetatively propagated orphaned crops and its implication for household food security in rural Kenya : A case of sweet potato (Ipomea batatas). Journal of Agriculture and Food Research, 2(10087), 1–8. https://doi.org/10.1016/j.jafr.2020.100087 Mwangi, M., & Kariuki, S. (2015). Factors Determining Adoption of New Agricultural Technology by Smallholder Farmers in Developing Countries. Journal of Economics and Sustainable Development, 6(5), 208–216. www.iiste.org Mwiti, F. K., Okello, J. J., Munei, K., & Low, J. (2020). Farmer demand for clean planting material of biofortified and non-biofortified vegetatively propagated crop varieties : The case of sweetpotato. Scientific African, 8, 1–10. https://doi.org/10.1016/j.sciaf.2020.e00400 Naluwairo, R. (2011). Investing in orphan crops to improve food and livelihood security of Uganda’s rural poor: Policy Gaps , Opportunities and Recommendations. In ACODE policy research series (Issue 43). Neela, S., & Fanta, S. W. (2019). Review on nutritional composition of orange-fleshed sweet potato and its role in management of vitamin A deficiency. Food Science and Nutrition, 7(6), 1920–1945. https://doi.org/10.1002/fsn3.1063 Ngailo, S., Shimelis, H. A., Sibiya, J., & Mtunda, K. (2016). Assessment of sweetpotato farming systems, production constraints and breeding priorities in eastern Tanzania. South African Journal of Plant and Soil, 33(2), 105–112. https://doi.org/10.1080/02571862.2015.1079933 Okello, J., Zhou, Y., Barker, I., & Schulte-Geldermann, E. (2019). Motivations and Mental Models Associated with Smallholder Farmers’ Adoption of Improved Agricultural Technology: Evidence from Use of Quality Seed Potato in Kenya. European Journal of Development Research, 31(2), 271–292. https://doi.org/10.1057/s41287-018-0152-5 Perman, R., Ma, Y., McGilvray, J., & Common, M. (2002). Natural Resource and Environmental Economics Database. In Marine Resource Economics (Vol. 7, Issue 4). https://doi.org/10.1086/mre.7.4.42629040 Pircher, T., & Almekinders, C. J. M. (2021). Making sense of farmers’ demand for seed of root, tuber and banana crops: a systematic review of methods. Food Security, Cgiar 2020. https://doi.org/10.1007/s12571-021-01157-9 Predmore, C., Topyan, K., & Apadula, L. T. (2021). Impact of process misconception in becker-degroot-marschak single response value elicitation procedures: An experimental investigation in consumer behavior using the ikea effect. Economies, 9(4). https://doi.org/10.3390/economies9040173 Republic of Kenya. (2017a). County Government of Kirinyaga, County Integrated development plan 2018–2022. Republic of Kenya. (2017b). Homabay county government second county integrated development plan 2018- 2022 (draft). Shee, A., Azzarri, C., & Haile, B. (2020). Farmers ’ Willingness to Pay for Improved Agricultural Technologies : Evidence from a Field Experiment in Tanzania. Sustainability, 12(216), 1–13. Shogren, J. F., Cho, S., Koo, C., List, J., Park, C., Polo, P., & Wilhelmi, R. (2001). Auction mechanisms and the measurement of WTP and WTA. Resource and Energy Economics, 23(2), 97–109. https://doi.org/10.1016/S0928-7655(00)00038-5 Simtowe, F., Marenya, P., Amondo, E., Worku, M., Rahut, D. B., & Erenstein, O. (2019). Heterogeneous seed access and information exposure: implications for the adoption of drought-tolerant maize varieties in Uganda. Agricultural and Food Economics, 7(1). https://doi.org/10.1186/s40100-019-0135-7 Singh, I., Squire, L., & Strauss, J. (1986). A survey of agricultural household models: Recent findings and policy implications. World Bank Economic Review, 1(1), 149–179. https://doi.org/10.1093/wber/1.1.149 Smith, M. D., Rabbitt, M. P., & Coleman- Jensen, A. (2017). Who are the World’s Food Insecure? New Evidence from the Food and Agriculture Organization’s Food Insecurity Experience Scale. World Development, 93, 402–412. https://doi.org/10.1016/j.worlddev.2017.01.006 Stevens, G. A., Bennett, J. E., Hennocq, Q., Lu, Y., De-regil, L. M., Rogers, L., Danaei, G., & Li, G. (2015). Trends and mortality eff ects of vitamin A defi ciency in children in 138 low-income and middle-income countries between 1991 and 2013 : a pooled analysis of population-based surveys. Lancet Glob Health, 528–536.https://doi.org/10.1016/S2214-109X(15)00039-X Taru, V. B., Kyagya, I. Z., & Mshelia, S. I. (2010). Profitability of Groundnut Production in Michika Local Government Area of Adamawa State Nigeria. Journal of Agricultural Sciences, 1(1), 25–29. https://doi.org/10.1080/09766898.2010.11884650 Waldman, K. B., Ortega, D. L., Richardson, R. B., & Snapp, S. S. (2017). Estimating demand for perennial pigeon pea in Malawi using choice experiments. Ecological Economics, 131, 222–230. https://doi.org/10.1016/j.ecolecon.2016.09.006 Wang, Q., Zhang, L., Wang, B., Yin, Z., Feng, C., & Wang, Q. (2010). Sweetpotato viruses in China. Crop Protection, 29(2), 110–114. https://doi.org/10.1016/j.cropro.2009.11.002 World Food Program. (2017). Creation of a Wealth Index.