The empirical literature on residential water demand employs various data aggregation methods, which depend on whether the aggregation is over consumption, sociodemographic variables, or both. In this study, we distinguish three dataset types—aggregated data, disaggregated data, and semi-aggregated data—to compare the consequences of using a large sample of semi-aggregated data vis-à-vis a small sample of fully disaggregated data on the water price elasticity estimates. We also analyze whether different aggregation levels in the sociodemographic variables affect the water price elasticity estimates when the number of observations is fixed. We employ a discrete-continuous choice model that considers that consumers face an increasing block price structure. Our results demonstrate that the water price elasticities depend upon the level of aggregation of the data used and the sample size. We also find that the water price elasticities are statistically different when comparing a large semi-aggregated sample with a small disaggregated sample.

关于住宅用水需求的经验文献采用了各种数据汇总方法，这取决于汇总是否是过度消费，社会人口统计学变量或两者兼而有之。在本研究中，我们区分了三种数据集类型（汇总数据，分解数据和半汇总数据），以比较使用较大的半汇总数据样本与较小的完全分解数据样本的后果。水价弹性估算。当观察次数固定时，我们还分析了社会人口学变量中不同的聚合水平是否会影响水价弹性估计。我们采用离散连续选择模型，该模型认为消费者面临着不断增长的大宗价格结构。我们的结果表明，水价弹性取决于所使用数据的汇总水平和样本规模。我们还发现，在比较大型半汇总样本和小型分类样本时，水价弹性在统计上是不同的。