Some regulatory reforms do not change just a specific signal that can be represented by a quantitative continuous variable, such as a tax rate, a price cap, or an emission threshold. The standard theory of reform in applied welfare economics (going back to contributions by e.g. Ramsey, Samuelson and Guesnerie) asks the question: What is the marginal effect on social welfare of changing a policy signal?However, reforms such as privatization, unbundling or liberalization of network industries are often described by 'packages' shifting a policy framework. It is increasingly frequent in the empirical evaluation of such reforms to use categorical variables, often in polytomous form, for instance describing unbundling steps (vertical integration, accounting, functional, legal, ownership separation) on a discrete numerical scale, such as those proposed by the OECD and other international bodies. We review recent econometric literature evaluating regulatory reforms using such variables (40 papers) and we discuss some methodological issues arising in this context. standards, administrative guidance and circulars (OECD, 2010). For instance, in the case of the European Union (EU), regulation of network services involves the adoption of both legislative and non-legislative acts, the so-called soft law (Maresca, 2013), 1 with complex implementation mechanisms (Goldberg, 1976). Moreover, the aim of such tools and procedures is often not to induce an immediate change in a signal, but rather to provide mechanisms that, under certain circumstances, should pave the way for such a change.A case in point is the regulation of segments of the telecom industry. For instance, "local loop unbundling" in European member states gives the right to entrants to use the incumbent telecom operator's local broadband network to offer their services directly to customers. 2 Clearly, the implementation of such a legislation cannot be described as a change in the vector of signals (Guthrie, 2006 and Nardotto et al., 2015). Rather, local loop unbundling can be interpreted as a modification of the regulatory policy framework that is expected to create the conditions for a change in signals and is thus not well approximated as a problem belonging to the RSG tradition.We discuss the empirical assessment of "packages" or reforms of policy framework (PFR) and focus on network industries, given the pervasiveness of the economic services they provide (e.g. energy, water, telecommunications, transport). The aim is to provide a consistent analytical scheme to help researchers and policy makers avoiding methodological pitfalls and interpretational errors that might bias the evaluation of reforms when the RSG approach is neither applicable, nor appropriate. We show that, notwithstanding the analysis of PFR cannot rely on well-established theoretical foundations, such as the RSG approach, empirical analyses are feasible and necessary, albeit interpretation of results and therefore design of policy recommendations requires caution.