Welfare impacts of import controls on Botswana's horticulture
研究了博茨瓦纳对橙子、土豆和洋葱的进口管制（许可证）对进口量、价格和福利的影响，发现管制导致进口下降、消费者损失和净社会损失增加，对进口替代效果有限。
Abstract Botswana has, for the past two decades, used import controls (permits) to regulate horticultural imports, and thereby promote economic diversification through import substitution. This article estimates import demand equations to capture the impact of import controls on horticultural imports (oranges, potatoes, and onions) into Botswana, using data for 1974 to 2001. Parameter estimates are used to compute nominal protection rates (NPRs) and welfare effects. Model‐generated NPRs are estimated at 191%, 75%, and 109% for oranges, potatoes, and onions, respectively. Imports of oranges, potatoes, and onions declined by 32%, 29%, and 35%, respectively, due to the implementation of import controls. Over time consumer losses and quota rents rose while producer gains declined. Net social losses also increased, implying that import controls became increasingly burdensome. It is argued that import controls have not been very effective in promoting import substitution. The study is important for the trade liberalization debate in the Southern African Customs Union (SACU) and within the Southern African Development Community (SADC), where import permits and other nontariff barriers are pervasive, have proliferated, and are a major hindrance to intraregional trade.