Tom Zawisza
taz21 [at] cam.ac.uk




Department of Economics
European University Institute
Villa La Fonte
Via delle Fontanelle 18, I-50014
San Domenico di Fiesole (FI)
ITALY
Tel: [+39] 055 4685 805



TOM ZAWISZA

Max Weber Fellow
European University Institute, Italy


Curriculum Vitae


Biography

I am a Max Weber Fellow at the European University Institute, and I am also affiliated to the Institute for Fiscal Studies in London.

My research focuses on analyzing the insurance and incentive effects of tax and welfare policy. I am looking at this problem from two perspectives: a theoretical one, where I model individuals as forward-looking agents making optimal saving and labour-supply choices; and an empirical one, where I attempt to identify structural parameters of models from the data.

I recently completed my PhD in Economics at the University of Cambridge, where I worked under the supervision of Professor Hamish Low.



Teaching

Girton Summer Schools, August 2017

International Finance Seminars:

Seminar 1 , Problem Set 1
Seminar 2 , Problem Set 2
Seminar 3, Problem Set 3
Seminar 4-5, Problem Set 4
Seminar 6, Problem Set 5
Seminar 7-8, Problem Set 6
Seminar 9-10, Problem Set 7
Seminar 11-12, Problem Set 8

Reading for Friday, 11th August:
Paul Krugman, "The Fear of China Syndrome"
Paul Krugman, "China, Japan, America"

Papers

"Taxation of Employment and Self-Employment: Evidence from Poland and Implications"

Abstract: In this paper we examine two crucial questions regarding the design of the optimal tax system, exploiting the 2009 Polish tax reforms. Firstly, we estimate the degree of substitution between the employment and self-employment tax bases on the extensive margin. In particular, we quantify the impact of changes in the differential in rates of taxation between the two tax bases on the propensity of taxpayers to declare any positive level of employment or self-employment income. Secondly, we contribute to the literature on elasticities of taxable income by providing estimates which are robust to changes in year-to-year income dynamics. We do this by exploiting variation in marginal tax rates around the 2009 reforms which occurs independently of an individual’s position in the income distribution as a result of joint reporting with a spouse. The estimates jointly make possible the decomposition of the deadweight losses of the tax reform into intensive and extensive-margin responses, with the contribution of the extensive margin found to be around 7 percent of the total.


(Work in progress) "Saving Behaviour of Disability Insurance Applicants: Are Waiting Times Effective Screening Devices?", with Hamish Low and Luigi Pistaferri

Abstract: The paper examines the consumption and saving behaviour of Disability Insurance (DI) applicants using a life-cycle model. We include a two-dimensional health process which determines an individuals health, and has implications for the chances of succeeding at the application and appeals stage. Saving behaviour for disability applicants of different types is examined, testing the validity of the predictions of Golosov and Tsyvinski (2006). The model provides an explanation for higher saving rates observed among moderately or 'non-verifiably' disabled individuals. The paper finally asks whether the length of the compulsory time out of the labour force before making a DI application can improve the DI system in terms of the insurance-efficiency trade-off.


(Work in progress) "Estimating Health Dynamics using a Dynamic Factor Model"

Abstract: This paper estimates the dynamics of health using a dynamic panel factor model on data from the Health and Retirement Study (HRS). It finds that the many potentially collinear health indicators found in the HRS can be summarized into two underlying factors. The first of these corresponds to subjective health measures, such as self-assessed mobility, while the other corresponds to more objective measures of health-care utilization, such as the number of overnight hospital stays. The dynamics of the factors are estimated as an underlying VAR process, and the discreteness of the HRS health indicators is dealt with by assuming a multinomial functional form. The model as a whole is estimated using the Generalized Autregressive Score (GAS) approach of Creal, Koopman and Lucas (2013).


"Banking Sector Efficiency in Sub-Saharan Africa", with François Boutin-Dufresne and Oral Williams, Journal of African Economies , 2014, 1-27.

Abstract: This paper examines the determinants of net interest margins in four regional blocks in Sub-Saharan Africa. Using bank-level data, we find that countries with a high level of operating costs, a high low level of non-interest income, a high ratio of equity to total assets and high treasury-bill interest rates have higher net interest margins. Moreover, high operating costs are associated with low measures of institutional quality and a small size of bank operations. We find support for the view that market structure is also partly responsible for high net interest margins in Sub-Saharan Africa, although quantitatively this effect is somewhat less important. High operating costs, high treasury-bill rates and a high ratio of equity to total assets and, indirectly, institutional factors such as the rule of law, are the most important factors in accounting for high interest margins in the East African Community, relative to other regions.