Department of Economics

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Browsing Department of Economics by Author "Bauknecht, Klaus Dieter"

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    A macroeconometric policy model of the South African economy based on weak rational expectations with an application to monetary policy
    (Stellenbosch : Stellenbosch University, 2000) Bauknecht, Klaus Dieter; Smit, B. W.; Stellenbosch University. Faculty of Economic & Management Sciences . Dept. of Economics .
    ENGLISH ABSTRACT: The Lucas critique states that if expectations are not explicitly dealt with, conventional econometric models are inappropriate for policy analyses, as their coefficients are not policy invariant. The inclusion of rational expectations in ·conventional model building has been the most common response to this critique. The concept of rational expectations has received several interpretations. In numerous studies, these expectations are associated with model consistent expectations in the sense that expectations and model solutions are identical. To derive a solution, these models require unique algorithms and assumptions regarding their terminal state, in particular when forward-looking expectations are present. An alternative that avoids these issues is the concept of weak rational expectations, which emphasises that expectation errors should not be systematic. Expectations are therefore formed on the basis of an underlying structure, but full knowledge of the model is not essential. The accommodation of this type of rational expectations is accomplished by means of an explicit specification of an expectations equation consistent with the macro econometric model's broad structure. The estimation of coefficients relating to expectations is achieved through an Instrumental Variable approach. In South Africa, monetary policy has been consistent and transparent in line with the recommendations of the De Kock Commission. This allows the modelling of the policy instrument of the South African Reserve Bank, i.e. the Bank rate, by means of a policy reaction function. Given this transparency in monetary policy, the accommodation of expectations of the Bank rate is essential in modelling the full impact of monetary policy and in avoiding the Lucas critique. This is accomplished through weak rational expectations, based on the reaction function of the Reserve Bank. The accommodation of expectations of a policy instrument also allows the modelling of anticipated and unanticipated policies as alternative assumptions regarding the expectations process can be made during simulations. Conventional econometric models emphasise the demand side of the economy, with equations focusing on private consumption, investment, exports and imports and possibly changes in inventories. In this study, particular emphasis in the model specification is also placed on the impact of monetary policy on government debt and debt servicing costs. Other dimensions of the model include the modelling of the money supply and balance of payments, short- and long-term interest rates, domestic prices, the exchange rate, the wage rate and employment as well as weakly rational expectations of inflation and the Bank rate. The model has been specified and estimated by usmg concepts such as cointegration and Error Correction modelling. Numerous tests, including the assessment of the Root Mean Square Percentage Error, have been employed to test the adequacy of the model. Similarly, tests are carried out to ensure weak rational expectations. Numerous simulations are carried out with the model and the results are compared to relevant alternative studies. The simulation results show that the reduction of inflation by means of only monetary policy could impose severe costs on the economy in terms of real sector volatility.