Universal Polar Decoding with Channel Knowledge at the Encoder

Polar coding over a class of binary discrete memoryless channels with channel knowledge at the encoder is studied. It is shown that polar codes achieve the capacity of convex and one-sided classes of symmetric channels

Re-proving Channel Polarization Theorems: An Extremality and Robustness Analysis

The general subject considered in this thesis is a recently discovered coding technique, polar coding, which is used to construct a class of error correction codes with unique properties. In his ground-breaking work, Ar{\i}kan proved that this class of codes, called polar codes, achieve the symmetric capacity --- the mutual information evaluated at the uniform input distribution ---of any stationary binary discrete memoryless channel with low complexity encoders and decoders requiring in the order of $O(N\log N)$ operations in the block-length $N$. This discovery settled the long standing open problem left by Shannon of finding low complexity codes achieving the channel capacity. Polar coding settled an open problem in information theory, yet opened plenty of challenging problems that need to be addressed. A significant part of this thesis is dedicated to advancing the knowledge about this technique in two directions. The first one provides a better understanding of polar coding by generalizing some of the existing results and discussing their implications, and the second one studies the robustness of the theory over communication models introducing various forms of uncertainty or variations into the probabilistic model of the channel.Comment: Preview of my PhD Thesis, EPFL, Lausanne, 2014. For the full version, see http://people.epfl.ch/mine.alsan/publication

Polarization as a novel architecture to boost the classical mismatched capacity of B-DMCs

We show that the mismatched capacity of binary discrete memoryless channels can be improved by channel combining and splitting via Ar{\i}kan's polar transformations. We also show that the improvement is possible even if the transformed channels are decoded with a mismatched polar decoder.Comment: Submitted to ISIT 201

Why did HIV decline in Uganda?

Uganda is widely viewed as a public health success for curtailing its HIV/AIDS epidemic in the early 1990s. We investigate the factors contributing to this decline. We first build a model of HIV transmission. Calibration of the model indicates that reduced pre-marital sexual activity among young women is the most important factor in the decline in HIV. We next explore what led young women to change their behavior. We estimate that approximately one-third the reduction in HIV in this cohort and almost 20 percent of the overall HIV decline was due to a gender-targeted education policy.

The Effect of Population Health on Foreign Direct Investment

We conduct a panel data analysis of 74 countries over 1980 2000 to investigate whether population health affects foreign direct investment inflows. Our main finding is that health has a positive and significant effect on such inflows for low- and middle-income countries. This finding is consistent with the view that health is an integral component of human capital in developing countries.

The Consequences of Population Health for Economic Performance

This chapter goes beyond the traditional economic thinking about the relationship between health and income – simply stated: wealth is needed to achieve health – by presenting evidence that population health is an important factor in strengthening economies and reducing poverty. The world's overarching framework for reducing poverty is expressed in the UN's eight Millennium Development Goals. Three of these eight goals pertain to health: reducing child mortality, improving maternal health, and combating HIV/AIDS, malaria, and other diseases. These potentially huge improvements in health are extremely important goals in themselves, and they serve as beacons toward which numerous development efforts are oriented. But these potential improvements in health are not only endpoints that we seek through a variety of means. The improvements are actually instruments for achieving economic growth and poverty reduction. That is, better health does not have to wait for an improved economy; measures to reduce the burden of disease, to give children healthy childhoods, to increase life expectancy will in themselves contribute to creating healthier economies.health, economic growth, developmennt, income, burden of disease