This paper examines the optimal direction of marginal income tax reform in the context of New Zealand, which recently reduced its top marginal income tax rate to one of the lowest in the OECD. A behavioural microsimulation model is used, in which social welfare functions are defined in terms of...

This paper examines the optimal direction of marginal income tax reform in the context of New Zealand, which recently reduced its top marginal income tax rate to one of the lowest in the OECD. A behavioural microsimulation model is used, in which social welfare functions are defined in terms of...

It is important for the design of tax policy to be able to measure reliably the income elasticity of tax revenue. This gives the extent to which tax revenues change as a result of a change in earnings. Analytical expressions for income tax revenue elasticities treat earnings as exogenous, so...

It is important for the design of tax policy to be able to measure reliably the income elasticity of tax revenue. This gives the extent to which tax revenues change as a result of a change in earnings. Analytical expressions for income tax revenue elasticities treat earnings as exogenous, so...

This paper reports a reweighting exercise for the New Zealand Household Economic Survey, which is the basis of the Treasury’s microsimulation model, TaxMod. Comparisons of benefit expenditures in a variety of demographic groups, along with population data, reveal that TaxMod estimates differ...

This paper presents a method of predicting individuals’ welfare changes (compensating and equivalent variations) arising from a tax or social security policy change in the context of behavioural microsimulation modelling, where individuals can choose between a limited number of discrete hours...

This paper presents two 'non-welfarist' approaches and one 'welfarist' approach to decompose changes in inequality and social welfare into three components. We distinguish the contributions of population, tax policy and labour supply behavioural effects. As an illustration, we decompose changes...