A quantitative evaluation of earnings risk and wealth inequality in the U.K.

This thesis studies inequality in several dimensions, with an emphasis on the analysis of inequality within and between groups (including by social class, occupation and education). It aims to identify factors that affect inequality and how income and wealth are distributed within society. In the first chapter, we examine the distributional effects of savings externalities. Incomplete markets models imply heterogeneous household savings behaviour which in turn generates pecuniary externalities via the interest rate. Conditional on differences in the processes determining household earnings for distinct groups in the population, these savings externalities may contribute to inequality. Working with an open economy heterogenous agent model, where the interest rate only partially responds to domestic asset supply, we find that differences in the earnings processes of British households with university and non-university educated heads entail savings externalities that increase wealth inequality between the groups and within the group of the non-university educated households. We further find that while the inefficiency effects of these externalities are quantitatively small, the distributional effects are sizeable. In the second chapter we examine the distributional effects of social pressure. In particular, we develop a theoretical framework where the cross-sectional distributions of hours, earnings, wealth and consumption are determined jointly with a set of expenditure targets defining peer and aspirational pressure for members of different social classes. We show existence of a stationary socio-economic equilibrium, under stochastic productivity and socio-professional class participation. We calibrate a model belonging to this framework using British data and find that it captures the main patterns of inequality, between and within the social groupings. We discover a complex pattern of how peer and aspirational pressure affects within- and cross-group inequality depending on both group membership and the inequality measure considered. A principal finding is that wealth and consumption inequality increase within groups who aspire to match social targets from a higher class, despite a reduction in within-group inequality in hours and earnings. Such aspirations can thus lead to social frustration, associated with increases in the dispersion of economic outcomes, and hence in the magnitude and likelihood of underachievement in meeting consumption targets. The third chapter seek to characterise the nature and cyclicality of household income risk in Great Britain. This chapter establishes new evidence on the cyclical behaviour of household income risk in Great Britain and assesses the role of social insurance policy in mitigating against this risk. We address these issues using the British Household Panel Survey (1991-2008) by decomposing stochastic idiosyncratic income into its transitory, persistent and fixed components. We then estimate how income risk, measured by the variance and the skewness of the probability distribution of shocks to the persistent component, varies between expansions and contractions of the aggregate economy. We first find that the volatility and left-skewness of these shocks is a-cyclical and counter-cyclical respectively. The latter implies a higher probability of receiving large negative income shocks in contractions. We also find that while social insurance (tax-benefits) policy reduces the levels of both measures of risk as well as the counter-cyclicality of the asymmetry measure, the mitigation effects work mainly via benefits

Prostate cancer recognition in ultrasound images

Our purpose is to aid medical doctors in prostate cancer detection via computer automated analysis of prostatic ultrasound imagery. Absorption of ultrasound signals is different in cancerous areas than in non-cancerous areas. The energy of the signal, the continuity of the signal, the autocorrelation function and frequency domain properties of prostatic ultrasound images are different in normal tissue than in cancerous tissue; This thesis presents an algorithm for automated cancer recognition in prostatic ultrasound imagery. Statistical and morphological based models are employed to classify regions of ultrasound imagery as either cancerous or non-cancerous. Application of our algorithm onto a limited set of cancerous and non-cancerous ultrasound images shows that our method has the ability to recognize cancer in cancerous ultrasound images. Misclassification occurs when cancerous tissue is classified as non-cancerous and noncancerous tissue is classified as cancerous. Occurrences of misclassification have been observed and investigated. (Abstract shortened by UMI.)

Wealth Inequality and Externalities from Ex Ante Skill Heterogeneity

This paper develops an incomplete markets model with state dependent (Markovian) stochastic earnings processes and ex ante skill heterogeneity corresponding to being university educated or not. Using the Wealth and Assets Survey for Great Britain, we find that the university educated group has higher average wealth, higher earnings risk but lower within group wealth inequality. Using estimates of the earnings processes for each group to calibrate the model, we find wealth inequality within and between the groups that is consistent with the data. Moreover, the predictions for overall wealth inequality are closer to the data, compared to the benchmark model with ex ante identical households. In this framework, ex ante skill heterogeneity generates a between-group pecuniary externality which in turn leads to the predicted differences in wealth inequality between the groups and works as an amplification mechanism to increase overall wealth inequality

Asymmetries in Earnings, Employment and Wage Risk in Great Britain

This paper examines the relationship between idiosyncratic risk in labour income and fluctuations in aggregate labour market quantities for Great Britain. We use data from the British Household Panel Survey (BHPS) for 1991-2008 and from the BHPS sub-sample of Understanding Society for 2010-2014. We measure idiosyncratic risk in labour income by the relevant moments of the distributions of earnings, employment and wage shocks across individuals. Our main finding is that idiosyncratic risk increases during contractions in the labour market. Furthermore, we find evidence of insurance, both at the household level and in the form of public insurance. However, private and public insurance mechanisms against an increase in idiosyncratic risk are less e¤ective for households whose head does not hold a University degree

The distributional implications of asymmetric income dynamics

Income dynamics differ between groups of households defined by whether the head has university education or not and have changed asymmetrically in Great Britain since 2008. Using a heterogenous agent incomplete markets model, we examine the quantitative implications of these differences for wealth inequality and for the distribution of conditional welfare losses. Within-group wealth inequality is higher for the non-university group and has increased since 2008 for both groups, while between-group inequality has also increased. Welfare losses are significantly higher for the non-university educated since 2008, and are driven by both a greater fall in mean income and a larger rise in income risk. Non-university educated households, which had initial wealth below the median and net labour income in the lower quintiles, suffered bigger losses. Social insurance policies beyond those currently in place can mitigate such welfare losses via tax and benefit redistributive mechanisms. For the broad majority of households, social insurance is valued more when it insures against the big adverse income shocks

Voices of the Turkana People

No abstract available

Outdoor and indoor path loss modeling at the sub-THz band

In this letter, we present new measurement results to model large-scale path loss at the sub-THz (141-145 GHz) band, for both indoor and outdoor scenarios. Extensive measurement campaigns have been carried out, taking into account both line-of-sight (LoS) and non line-of-sight (NLoS) propagation. For all considered propagation scenarios, existing omni-directional and directional path loss model have been developed, based on the so-called close-in (CI) free-space reference distance model. Moreover, path loss modeling is applied for the 2nd and 3rd strongest multipath components (MPCs). Thus, path loss exponent and large-scale shadow fading estimates are provided. Moreover, power angular spread analysis is depicted, using power angular information up to the 3rd strongest MP

Cyclical labour income risk in Great Britain

This paper provides new evidence on the cyclical behaviour of household labour income risk in Great Britain and the role of social insurance policy in mitigating against this source of income risk. To achieve this, we decompose stochastic idiosyncratic household income into its transitory and persistent components. We focus our analysis of income risk captured by the second to fourth moments of the probability distribution of shocks to the persistent component of income. We find that household labour income risk increases during contractions via changes in third and fourth central moments of persistent shocks to labour income, while the variance remains acyclical. We also find that economic policy has reduced the level of risk exposure and its increase during contractions via benefits rather than tax policies