Trade Adjustment Costs in Developing Countries: - World Bank ...

The Duration of Trade Relationships 277We follow Rauch (1999) and classify commodities into three categories: homogeneous,reference priced, and differentiated. Rauch classified products tradedon an organized exchange as homogeneous goods. Products not sold on exchangesbut whose benchmark prices exist were classified as reference priced;all other products were deemed differentiated.We begin by examining nonparametric Kaplan–Meier estimates of survivalfunctions across product types. Estimates are graphed in Figure 17.3. As seen, mediansurvival times are extraordinarily short: five years for differentiated productsand two years for reference priced and homogeneous goods. Half of the traderelationships involving reference priced and homogeneous goods fail during thefirst two years. We report the nonparametric Kaplan–Meier estimates of survivalfunctions across product types in Table 17.3. As predicted by the model, differentiatedproducts dominate the other product types in their survival rates, at anystage of a relationship. In year one, 69 per cent of relationships involving differentiatedgoods survive to year two, while only 55 and 59 per cent of relationshipsinvolving homogeneous and reference priced goods do so. By year four,these rates decline to 52 per cent for differentiated and 33 per cent for homogeneousgoods. Between years four and 12 survival rates are stable declining by just7 percentage points for each product type. The differences in survival across producttypes are statistically significant. Similar results are found for the HS data(lower part of the table).Table 17.3: Kaplan-Meier Survival Rates 12Differentiated Products Reference Priced Products Homogeneous GoodsData Year 1 Year 4 Year 12 Year 1 Year 4 Year 12 Year 1 Year 4 Year 121972-1988 (7-digit TSUSA)Benchmark 0.69 0.52 0.45 0.59 0.38 0.31 0.55 0.33 0.25Obs>$100,000 0.92 0.86 0.83 0.80 0.66 0.60 0.69 0.49 0.411989-2001 (10-digit HS)Benchmark 0.66 0.48 0.44 0.65 0.46 0.40 0.62 0.40 0.35Obs>$100,000 0.92 0.85 0.83 0.86 0.75 0.71 0.76 0.59 0.55Note: The survival functions across the product types within each dataset are statisticallysignificant at the 1% level using the logrank testThe model’s predictions regarding starting size are also supported. In order toinvestigate whether small, valued spells are at greatest risk we filtered out smalldollar-value observations; that is, we eliminated spells with trade in the first yearbelow some minimum level. We then estimate survival functions for each producttype after dropping the small-valued observations. In Table 17.3 we reportsurvival rates based on dropping all observations where the value of trade in thefirst year of the spell was less than $100,000.12 Extract from Table 2 in Besedeš and Prusa (2006b).