# NOTES

> 1 Research on this topic, discussed in more detail below, dates to Parti and Parti [1980], Dubin and McFadden [1984] and Hsiao and Mountain [1985]. Recent influential contributions include Reiss and White [2005/2008].

> 2 Greater Buenos Aires (Gran Buenos Aires) is an urban metropolitan area that comprises the city of Buenos Aires and 24 adjacent municipalities (National Institute of Statistics and Censuses [2003]). According to the 2010 population census it has 12.8 million inhabitants, nearly a third of the total Argentinean population.

> 3 The evidence we provide may therefore contribute to the discussion on the relative importance of prices versus nudges for steering consumers' behaviors (Loewenstein and Ubel [2010]).

> 4 Focusing on the gas market in the US, Davis and Muehlegger [2010] exploit variation in wholesale prices to estimate the price elasticity of demand in the residential sector. We believe that our RD estimates add value to this literature in that they: (1) are less likely to be affected by unobserved heterogeneity across households; and (2) emphasize the role of imperfect information in shaping consumer behavior in this market. See also Jessoe and Rapson [2011] for a recent analysis of commercial and industrial demand response under mandatory time-of-use electricity pricing in Connecticut.

> 5 To preserve confidentiality of its broad customer base, the company refused to provide us with data on consumers from other categories.

> 6 For simplicity, in this section we focus on consumers with annual accumulated consumption between 1,251 and 1,800 cubic meters who can therefore face only two potential prices (see Table I).

> 7 The survey used records from 2952 households in order to obtain 353 valid responses from the member of the household that is responsible for paying the gas bills. A failure to produce a valid interview occurred when the enumerator: (1) was unable to establish a phone conversation with any member of the household; (2) was unable to reach the person responsible for paying the gas bills; or (3) the person responsible for paying the gas bills refused to cooperate. The response rate of the survey (12%) is well in line with that of recent phone surveys in the US-a recent study by the Pew Research Center [2012] reports that a standard survey yields a response rate of 9%.

> 8 The full set of results is available upon request.

> 9 Measured consumption is always rounded to the nearest integer, and hence we cluster the standard errors at the unit levels of the running variable.

> 10 To verify if the amount billed in period 0 actually followed the tariff structure prevailing at the time, we have predicted the bill by applying the prevailing unit prices, adding the fixed charge and applying the minimum billed amount. The correlation between predicted and actual bills is 0.98, suggesting that bills in period 0 followed closely the prevailing price schedule.

> 11 For example, if a household receives a guest in period 0 gas demand would likely increase in that period, returning to normal levels in period 1 once the guest leaves.

> 12 This elasticity corresponds to the inverse of the ratio between the percentage increase in the unit price faced by consumers just above the threshold (25%) and the estimated change in gas consumption during the subsequent twomonth period (-3.8% of average gas consumption).

> 13 Reiss and White [2008] survey earlier literature using cross-sectional survey data for household electricity consumption, and conclude that the cross-sectional estimates vary widely, with typical values near -0.3.

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