This thesis is composed of three independent articles. The first two chapters are on the topic of asset bubbles. In the first chapter, I study the interactions between rational asset bubbles and product market competition. I build a theoretical model where I show that asset bubbles, by providing a production or entry subsidy, may have a pro-competitive effect and force firms to expand and cut profit margins. I use the model to interpret the evidence of two famous bubble episodes: the British railway mania of the 1840s and the dotcom bubble of the 1990s. In the second chapter, I provide a comprehensive characterization of non-fundamental stock price fluctuations at the industry level. Among other things, I show that overvaluation shocks tend to be more important in industries with higher profit margins or higher R&D intensity. I also document that, in periods of high over-valuation, stock market entrants tend to be less productive. In the third and last chapter I characterize the evolution of business dynamism in Spain between 1995 and 2007. Consistent with the evidence for other developed countries, I document a significant decline in the Spanish firm entry and exit rates over this period. I also show that, when compared to incumbents of the same industry, young firms have become relatively more productive. I build a model featuring firm dynamics and financial frictions to show how a decline in interest rates can explain these trends.

This dissertation consists of three chapters about how access to financial markets and composition of the labor market determine aggregate macroeconomic outcomes. The first chapter examines the macroeconomic consequences of credit uncertainty using a structural vector autoregression model with stochastic volatility (SVAR-SV). Credit supply conditions in the U.S. is captured by the banks' reports on how credit standards for approving loans have change over time (Bank Lending Standards). The empirical analysis shows that the volatility of macroeconomic and financial variables rises in response to an increase in the credit uncertainty shock. The economic activity falls and credit growth and related interest rates decrease persistently. Moreover, credit volatility shocks explain around 10% of the FEV of endogenous variables. A dissagregated analysis shows that the effect of these shocks are mainly explained by their effects on the corporate business sector. The second chapter studies the role of time-varying credit limits through the lens of a life cycle incomplete markets model calibrated for the U.S. Changes in credit card limits are explained by observable household characteristics and the estimated unobservable variation is quite large. The quantitative exercise shows that even though young households are more indebted in an economy with stochastic borrowing limits, aggregate consumption is not greatly affected by transitory or persistent shocks of this type. However, in the presence of these shocks, households lose the ability to self-insure against other uninsurable idiosyncratic shocks, e.g., labor income shocks. A disaggregated analysis shows that the loss of self-insurance capacity is mainly explained by the effects that stochastic borrowing limits have on the wealth distribution, the precautionary savings channel households have to face unexpected risks. The third chapter studies the role of informal markets to explain economic and demographic variables during a pandemic. The quantitative exercise shows that lockdown policies are less effective in economies with large informal markets, infection and death rates will not decrease as much as formal economies. Moreover, the size of the recession would be exacerbated because informal activities are not counted in the calculation of the GDP. To generate similar results to an economy with only formal markets, the economy with informal markets must implement more severe containment policies.

This dissertation consists of three essays. The first essay, entitled "Dynamic Market Participation and Endogenous Information Aggregation", studies information aggregation in financial markets with recurrent investor exit and entry. The paper considers a dynamic general equilibrium model of asset trading with private information and collateral constraints. Investors differ in their aversion to Knightian uncertainty: when uncertainty is high, some investors exit the market. Since exiting investors' information is not fully revealed by prices, conditional return volatility and risk premia both increase. I use data on institutional investors' holdings of individual stocks to show that investor exit rates indeed comove with return volatility and help forecast it. The model also implies that exit is more likely when wealth is more concentrated in the hands of less uncertainty averse investors. The model thus predicts more exit toward the end of a long boom, as seen in the data. Moreover, economies with looser collateral constraints should see more volatility due to exit and partial revelation. The second essay, entitled "The (Un)importance of Mobility in the Great Recession", is based on a paper co-authored with Siddharth Kothari and Itay Saporta-Eksten. Unemployment during and after the Great Recession has been persistently high. One concern is that the housing bust reduced mobility and prevented workers from moving for jobs. The paper characterizes flows out of unemployment that are related to mobility to construct an upper bound on the effect of mobility on unemployment between 2007 and 2012. The effect of mobility is always small: Using pre-recession mobility rates, decreased mobility can account for only an 11 basis points increase in the unemployment rate over the period. Using dynamics of renter mobility in this period to calculate homeowner counterfactual mobility, can account for an 8 basis points increase. Using the highest mobility rate observed in the data, reduced mobility accounts for only a 34 basis points increase in the unemployment rate. The third essay, entitled "Long-term Bonds in a Housing Model", looks into a housing model where mortgages are modeled as a long-term bond. Most house purchases in the US are financed through a mortgage with maturity between 15 and 30 years. This essay studies house price dynamics when modeling mortgages as long-term bonds instead of the more standard one-period bond. With this new feature in the model, results show that the equilibrium price-rent ratio and mortgages borrowing are much less sensitive to changes in the interest rates. In addition, the model can generate negative equity, which matches the presence of negative equity in the housing market downturn in data.

This volume focuses on current issues of debate in the area of modern macroeconomics and money, written from (a broadly interpreted) post Keynesian perspective. The papers connect with Philip Arestis' contributions to macroeconomics and money, and pay tribute to his distinguished career.

This collection of articles and papers has been organised under a limited number of specific themes in international financial economics, including balance of payment theory and policy, the activities of the IMF, Special Drawing Rights, the role of the private financial markets, and the international economic order. A unifying theme running through all the essays is that some degree of management of international financial affairs is desirable. The book has a strong policy orientation and should be of interest to students and practitioners of international financial economics alike.