This thesis consists of three main empirical chapters on the effect of stock liquidity on exchange markets. The first (Chapter 2) investigates the pricing ability of an illiquidity measure, namely the Amihud measure (Amihud, 2002), in different sample periods. The second (Chapter 3) determines the causal link between two well-known market quality factors liquidity and idiosyncratic volatility adopting two-stage least squares methodology (2SLS). The last empirical chapter (Chapter 4) revisits the limits to arbitrage theory and studies the link between stock liquidity and momentum anomaly profit, employing the difference-in-differences approach. The overall contribution of this thesis is to employ causal techniques in the context of asset pricing in order to eliminate potential endogeneity problems while investigating the relation between stock liquidity and exchange markets. Chapter 2 investigates whether the Amihud measure is priced differently if the investor is optimistic or, conversely, pessimistic about the future of the stock markets. The results of the chapter show that Amihud measure is priced in the low-sentiment period and that there is illiquidity premium when investor sentiment is low. Chapter 3 studies whether a change in stock liquidity has an impact on idiosyncratic volatility, employing causal techniques. Prior studies investigate the link between liquidity and idiosyncratic volatility but none focus on the potential problem of reverse causality. To overcome this reverse causality problem, I use the exogenous event of decimalisation as an instrumental variable and employ two-stage least squares approach to identify the impact of liquidity on idiosyncratic volatility. The results of the chapter suggest that an increase in illiquidity causes an increase in idiosyncratic volatility. As an additional result, my study shows that reduction in the tick size as a result of decimalisation improves firm-level stock liquidity. Chapter 4 examines whether liquid stocks earn more momentum anomaly profits compare to illiquid stocks, using the implementation of different tick sizes for different price ranges in the American Stock Exchange (AMEX) between February 1995 and April 1997. This programme provides a plausibly exogenous variation to disentangle the endogeneity issue and allows me to examine the impact of liquidity on momentum, by clearly exploiting the difference-in-difference framework. The results of the chapter show that liquid stocks earn more momentum profit than illiquid stocks.

As the demand for liquidity risk management has increased, the importance of comprehensive liquidity assessments of exchanges has been highlighted. This thesis investigates the liquidity on the Nasdaq OMX Stockholm exchange by using daily end of day data. The transaction cost is evaluated using the Holden model and the price impact from trading is evaluated using the Illiq model. Considering the three segments; small cap, mid cap, and large cap, the results suggest that both the transaction cost and price impact is highest for small cap stocks and lowest for large cap stocks. It is also shown that the transaction cost has decreased between 2002-03-20 and 2012-01-06 for all three segments although the cost is increasing for the small cap segment again. No decrease in price impact over this time period could be found. The data behind the results has then been used to create a combined liquidity measure with the purpose of indicating the liquidity condition of a mutual fund. The combined measure can also be used to assess whether it is price impact or transaction cost that contributes most to the liquidity cost when liquidating stocks or reveal what stocks in a portfolio that are the most illiquid. It is hence suggested as a tool for assessing large portfolios.

This thesis aims to investigate the influence of earnings news on stock liquidity and the relationship between information asymmetry cost component and Post Earnings Announcement Drift in different equity markets. The scope of this research includes 1821 firms from three leading countries in capital trading, the United States, United Kingdom, and France. The first part of empirical work, the univariate panel analysis, shows that price reaction, volume response and liquidity effect are profound during short term event window length and reduce over time when the news ceases, The second part, a multivariate regression analysis which uses Generalised Method of Movement to capture both the problems of a likely presence of endogeneity between the explanatory variables and cross-stock heterogeneity,shows that the impact of earnings announcement on stock liquidity can split in two directions. The immediate effect is the shock after the news, causing stock liquidity to decrease immediately by lifting the illiquidity function upward. After the event, from the new increased position of illiquidity function, stock liquidity improves over time due to the trading volume increases and shifts the slope of illiquidity function downward. The overall effects at a point of time will be the total impact of the two side effects. And as shown in the results, the overall impact on the US and UK markets are that stock liquidity decreases and that on Euronext Paris the stock liquidity increases. Given that in accounting there are two types of systems of which common law system includes the US, UK and others, and code law system includes France and the rest, the above results could suggest the difference between the two systems is that the information asymmetry component dominates the bid-ask spread in common law countries as in the US and UK markets while the cost of trading dominates the bid-ask spreads in code law countries such as France. Finally, it is shown that there are several determinants of the PEAD, of which stock liquidity is one. Earnings news changes the stock liquidity, and therefore stock liquidity plays a role in the market response. When earnings news is released, it initially creates a gap between the informed traders and the uninformed traders, increasing the bid ask spread. Over time, this information gap decreases, however in the meantime more information on the market increases trading volume and reduces trading cost, leading to another part of the bid ask spread decreasing or stock liquidity improving. After decomposing bid ask spread into information asymmetry cost and cost of trading components, the final part of empirical analysis shows that information asymmetry cost component provides a partial explanation for PEAD in the London Stock Exchange and Euronext Paris.

No contexto da Teoria da Divulgação, que estuda os fenômenos relacionados à divulgação da informação, este estudo teve como objetivo estudar a relação entre liquidez das ações e o nível de divulgação das empresas brasileiras de capital aberto do setor de Siderurgia e Metalurgia no período de 1998 a 2007. Para mensurar o conceito de liquidez de ações adotou-se diversas métricas nessa pesquisa, como também o uso de metodologia desenvolvida por Lima (2007) para calcular o índice de divulgação. O interesse nessa linha surge pelo grande número de estudos no mercado internacional sobre o tema, porém não tão desenvolvido no Brasil. Para realizar esta pesquisa foram feitas análises de estatística descritiva, de posição com o uso do teste U de Mann-Whitney, correlação de Spearman e regressões com dados dispostos em painel com correção de Newey-West. Como resultado, verificou-se uma relação positiva estatisticamente e economicamente significante entre divulgação e liquidez de ações, coerente com pesquisas anteriores, principalmente as estrangeiras. Com os resultados encontrados, pode-se inferir que, conforme Amihud e Mendelson (1986), a liquidez pode influenciar o custo de capital das empresas, especificamente no setor estudado, de modo que a hipótese alternativa do trabalho não pode ser rejeitada. / In the context of the Theory of Disclosure, which studies phenomena related to information dissemination, this research aimed to study the relation between stock liquidity and the level of disclosure of Brazilian publicly-traded companies from the Iron and Steel sector between 1998 and 2007. To measure the stock liquidity concept, different measurement tools were adopted, as well as the method developed by Lima (2007) to calculate the disclosure index. The interest in this research line is due to the large number of studies about this theme in the international market, which is not so developed in Brazil. Descriptive statistical analyses of position were performed, using Mann-Whitneys U-test, Spearmans correlation and regressions with panel data and Newey-West standard errors. As a result, a statistically and economically significant positive correlation was found between disclosure and stock liquidity, in line with earlier and mainly foreign research. Based on these results, it can be inferred that, in line with Amihud and Mendelson (1986), liquidity can influence companies cost of capital, specifically in the sector under analysis, so that the alternative research hypothesis cannot be rejected.

Bakgrund: Det har tidigare konstaterats att det existerar ett samband mellan aktiers likviditet och dess avkastning. Bevis för detta har främst gått att finna på utländska aktiemarknader. På den svenska aktiemarknaden har tidigare utförda studier konstaterat att detta samband inte existerar. Vi vill därför göra en studie på den svenska aktiemarknaden, vilken delvis innefattar en ny tidsperiod för att se om någon likviditetspremie existerar. Syfte: Vårt syfte med denna studie var att undersöka om det är möjligt att uppnå en högre avkastning genom att investera i en portfölj med relativt sett illikvida aktier jämfört med en portfölj bestående av likvida aktier på Stockholmsbörsen samt undersöka om faktorerna likviditet, betavärde samt företagsstorlek signifikant påverkar portföljernas eventuella överavkastning jämfört mot ett lämpligt index. Metod: Vi har skapat tre olika portföljer, med tio aktier i varje vilka representerar de minst, mitterst och mest likvida aktierna enligt vårt valda likviditetsmått, aktieomsättningshastighet. Likviditetsmåttet laggar en månad för att kunna användas som investeringsstrategi. Vi har studerat portföljernas värdeutveckling under perioden september 2003 till december 2011 för att se om portföljernas olika likviditet påverkar avkastningen. Genom regressionsanalyser där aktieomsättningshastighet, betavärde samt storleken använts som oberoende variabler har vi försökt förklara portföljernas överavkastning mot AFGX. Resultat: Vi har kommit fram till att det inte existerar någon likviditetspremie på Stockholmsbörsen under vår valda undersökningsperiod. Det samma gäller under uppåt- respektive nedåtgående marknadstrend. Det enda fallet där en mer illikvid portfölj presterar bäst är under januari månad. / Background: Earlier studies have concluded that there is a connection between a stock’s liquidity and its yield. Proof of this connection has mainly been found on foreign stock exchanges. On the Swedish stock market, earlier studies have concluded that this connection may not exist. The authors therefore intend to do a liquidity study on the Swedish stock market on a partly new time period to see whether this liquidity premium exists or not. Aim: The aim with this study is to investigate if there is a possibility to achieve a higher yield by investing in a portfolio consisting of relatively illiquid stocks contrary a portfolio with highly liquid stocks. We also want to investigate if the factors: liquidity, beta value and company size have a significant impact on the portfolios possible excess return in relation to an appropriate index. Completion: In this study, the authors have constructed three different portfolios consisting of ten stocks, each which represent the least, middle, and highest liquid stocks according to our liquidity measure. This measure has a one-month lag to make it possible to use as an active investment strategy. The authors have studied the portfolios growth during the period September 2003 to December 2011 to investigate if the difference in liquidity has any impact on the return. Through regression analysis, where stock turnover ratio, beta value and company size has been used as independent variables, the study tries to explain the portfolios excess return over the AFGX index. Results: The study concludes that there is no significant liquidity premium during our chosen time period. The same conclusion is drawn on the sub-periods with both an up going and down going market trend. The only period during which an illiquid portfolio outperforms a liquid portfolio is during the month of January.

This thesis examines the impact of FTSE 100 index revisions on the various aspects of stock market quality and the cost of equity capital. Our study spans over the period 1986-2009. Our analyses indicate that the index membership enhances all aspects of liquidity, including trading continuity, trading cost and price impact. We also show that the liquidity premium and the cost of equity capital decrease significantly after additions, but do not exhibit any significant change following deletions. The finding that investment opportunities increases after additions, but do not decline following deletions suggests that the benefits of joining an index are likely to be permanent. This evidence is consistent with the investor awareness hypothesis view of Chen et al. (2004, 2006), which suggests that investors' awareness improve when a stock becomes a member of an index, but do not diminish after it is removal from the index. Finally, we report significant changes in the comovement of stock returns with the FTSE 100 index around the revision events. These changes are driven mainly by noise-related factors and partly by fundamental-related factors.

Innovationsförmåga är viktigt för företags konkurrenskraft och är kopplad till ekonomisk tillväxt och ekologisk hållbarhet i samhället. Tidigare forskning har undersökt aktielikviditetens inverkan på innovationsförmågan hos amerikanska bolag men har kommit fram till motstridiga resultat. Vi utför multipla linjära regressionsanalyser på data från de 36 företag noterade på Stockholmsbörsens primära marknader som har varit noterade och haft FoU-kostnader 2004-2013. Vi kan inte finna ett statistiskt signifikant samband mellan aktielikviditet och innovationsförmåga. Indelning av företag efter storlek eller ägarstruktur påverkar inte det förhållandet. Vi tänker oss att kontrollen över svenska börsbolag är så pass koncentrerad att förändrad aktielikviditet inte påverkar makt-förhållandena till en sådan grad att företagsledningars incitament till innovativa satsningar förändras. Framtida forskning får utröna närmre varför det inte tycks finnas ett samband på den svenska marknaden trots att det eventuellt finns det på den amerikanska.

Dividend policy, its determinants, and its impact on firm value are of significant academic interest, and many theories and explanations have been posited on the subject over the years, but there has not been a universal agreement. This thesis examines the links between dividend policy, various aspects of stock liquidity and price informativeness. We study a sample of UK firms over the period from 1996-2013. We show that, on average, stocks of dividend payers have significantly lower bid–ask spread and a lower illiquidity ratio than their counterparts of non-dividend payers. We also find that stocks of high-dividend payers are more liquid than those of firms that pay low or no dividends. These findings are consistent with the predictions of asymmetric information that posit that paying dividends reveals inside information to the market and hence decreases the level of asymmetric information, leading to higher stock liquidity. In the subsequent analysis, we suggest and examine a new channel through which dividend policy can impact firm value. Specifically, we show that dividend payers are less exposed to shocks in the aggregate market liquidity than non-dividend payers. Similarly, we find that the systematic liquidity risk is negatively associated with amount of dividends. Finally, in the context of signalling and agency costs models, we show that dividends are negatively related to stock price informativeness and that this relationship is stronger for firms with lower stock liquidity. The findings imply that dividend policy can both affect and be affected by stock markets.

No contexto da Teoria da Divulgação, que estuda os fenômenos relacionados à divulgação da informação, este estudo teve como objetivo estudar a relação entre liquidez das ações e o nível de divulgação das empresas brasileiras de capital aberto do setor de Siderurgia e Metalurgia no período de 1998 a 2007. Para mensurar o conceito de liquidez de ações adotou-se diversas métricas nessa pesquisa, como também o uso de metodologia desenvolvida por Lima (2007) para calcular o índice de divulgação. O interesse nessa linha surge pelo grande número de estudos no mercado internacional sobre o tema, porém não tão desenvolvido no Brasil. Para realizar esta pesquisa foram feitas análises de estatística descritiva, de posição com o uso do teste U de Mann-Whitney, correlação de Spearman e regressões com dados dispostos em painel com correção de Newey-West. Como resultado, verificou-se uma relação positiva estatisticamente e economicamente significante entre divulgação e liquidez de ações, coerente com pesquisas anteriores, principalmente as estrangeiras. Com os resultados encontrados, pode-se inferir que, conforme Amihud e Mendelson (1986), a liquidez pode influenciar o custo de capital das empresas, especificamente no setor estudado, de modo que a hipótese alternativa do trabalho não pode ser rejeitada. / In the context of the Theory of Disclosure, which studies phenomena related to information dissemination, this research aimed to study the relation between stock liquidity and the level of disclosure of Brazilian publicly-traded companies from the Iron and Steel sector between 1998 and 2007. To measure the stock liquidity concept, different measurement tools were adopted, as well as the method developed by Lima (2007) to calculate the disclosure index. The interest in this research line is due to the large number of studies about this theme in the international market, which is not so developed in Brazil. Descriptive statistical analyses of position were performed, using Mann-Whitneys U-test, Spearmans correlation and regressions with panel data and Newey-West standard errors. As a result, a statistically and economically significant positive correlation was found between disclosure and stock liquidity, in line with earlier and mainly foreign research. Based on these results, it can be inferred that, in line with Amihud and Mendelson (1986), liquidity can influence companies cost of capital, specifically in the sector under analysis, so that the alternative research hypothesis cannot be rejected.

This thesis examines the impact of FTSE 100 index revisions on the various aspects of stock market quality and the cost of equity capital. Our study spans over the period 1986¿2009. Our analyses indicate that the index membership enhances all aspects of liquidity, including trading continuity, trading cost and price impact. We also show that the liquidity premium and the cost of equity capital decrease significantly after additions, but do not exhibit any significant change following deletions. The finding that investment opportunities increases after additions, but do not decline following deletions suggests that the benefits of joining an index are likely to be permanent. This evidence is consistent with the investor awareness hypothesis view of Chen et al. (2004, 2006), which suggests that investors¿ awareness improve when a stock becomes a member of an index, but do not diminish after it is removal from the index. Finally, we report significant changes in the comovement of stock returns with the FTSE 100 index around the revision events. These changes are driven mainly by noise-related factors and partly by fundamental-related factors. / International Fellows Program, USA, (IFP) and American-Mideast-Educational and Training Services, Inc. (AMIDEAST).