birth cohorts, attempt to compute death tolls using the death probabilities calculated in my analysis and baseline data provided in Heuveline (2001 (b)). This provides an idea of the extent of the underestimation caused by the sample approach. As the appendix shows a very substantial degree of underestimation, it is possible to conclude that most differences obtained using the sample approach probably represents underestimates since the families in which deaths were most likely to occur between 1975 and 1979 are underrepresented in the sample. I have also chosen not to include the respondent in the counts, but only her siblings, because otherwise mortality would be further underestimated since, by definition, respondents are all survivors. Another issue is international migration (widespread as many Cambodians took refuge in neighboring Thailand or Vietnam): to the extent that families migrated and did not come back to Cambodia and if those families experienced a different mortality rate<sup>4</sup> , this might induce some bias.

Despite these shortcomings, the mortality estimates derived from the siblings’ data from a large representative sample represent a useful contribution. First, even if they underestimate the number of deaths, they provide an accurate measure of the impact of mortality on the current population structure in Cambodia. Such data also allow the analysis to address questions about the timing and the socio-economic distribution of excess mortality that cannot be answered with the reconstruction approach.

# **_II.1 Extent and timing of excess mortality_**

As argued above, this section of the paper does not attempt to calculate “the number”, i.e. an estimate of the excess number of deaths during the Khmer Rouge period.<sup>5</sup> It rather describes the impact of the excess mortality during the period on the current population structure in Cambodia.

4 Information about past international migrations is scant in the Demographic and Health Survey. It is known whether a respondent always resided at the same place or not. If not, the length of the stay in the current residence and the type (urban, rural, abroad) of the previous residence is known. It is therefore possible to identify 130 respondents whose previous place of residence was abroad. The mortality experienced during the 1975-79 period by the siblings of respondents whose previous residence was abroad and later came back to Cambodia differ from the rest of the population: for all ages and genders together, their death probability for 1975-79 was 5.09% (C.I. 3.00-7.18), while for siblings for which there is no indication that the sister migrated abroad, the death probability was 9.60% (C.I. 9.33-9.87). This seems to point to a lower mortality experience for families who migrated abroad. However, the survey gives a very incomplete picture of international migration: there is no information about when the migration took place and the survey only yields information in case it is the residence that immediately preceded the current one that was abroad. In addition, the survey misses families that migrated out of Cambodia and never came back.

5 See however the appendix for a comparison between the reconstruction and the sample approach for selected birth cohorts.

4