A Note on Proxy Variables and Instrument Variable Regression

This is a note about proxy variables and instruments for identification of structural parameters in regression models. We have experienced that in the econometric textbooks these two issues are treated separately, although in practice these two concepts are very often combined. Usually, proxy variables are inserted in instrument variable regressions with the motivation they are exogenous. Implicitly meaning they are exogenous in a reduced form model and not in a structural model. Actually if these variables are exogenous they should be redundant in the structural model, e.g. IQ as a proxy for ability. Valid proxies reduce unexplained variation and increases the efficiency of the estimator of the structural parameter of interest. This is especially important in situations when the instrument is weak. With a simple example we demonstrate what is required of a proxy and an instrument when they are combined. It turns out that when a researcher has a valid instrument the requirements on the proxy variable is weaker than if no such instrument exists

Managing ServerHotel

This graduate study was assigned by Unisys Oy Ab. The purpose of this study was to find tools to monitor and manage servers and objects in a hosting environment and to remotely connect to the managed objects. Better solutions for promised services were also researched. Unisys provides a ServerHotel service to other businesses which do not have time or resources to manage their own network, servers or applications. Contracts are based on a Service Level Agreement where service level is agreed upon according to the customer's needs. These needs have created a demand for management tools. Unisys wanted to find the most appropriate tools for its hosting environment to fulfill the agreed service level with reasonable costs. The theory consists of literary research focusing on general agreements used in the Finnish IT business, different types of monitoring and management tools and the common protocols used inthem. The theory focuses mainly on the central elements of the above mentioned topics and on their positive and negative features. The second part of the study focuses on general hosting agreements and what management tools Unisys has selected for hosting and why. It also gives a more detailed account of the hosting environment and its features in more detail. Because of the results of the study Unisys decided to use Servers Alive to monitor network and MS applications’ services. Cacti was chosen to monitor disk spaces, which gives us an idea of future disk growth. For remote connections the Microsoft’s Remote Desktop tool was the mostappropriate when the connection was tunneled through Secure Shell (SSH). Finding proper tools for the intended purposes with cost-conscious financial resources proved challenging. This study showed that if required, it is possible to build a professional hosting environment.

Load balancing solution and evaluation of F5 content switch equipment

The Thesis focused on hardware based Load balancing solution of web traffic through a load balancer F5 content switch. In this project, the implemented scenario for distributing HTTPtraffic load is based on different CPU usages (processing speed) of multiple member servers.Two widely used load balancing algorithms Round Robin (RR) and Ratio model (weighted Round Robin) are implemented through F5 load balancer. For evaluating the performance of F5 content switch, some experimental tests has been taken on implemented scenarios using RR and Ratio model load balancing algorithms. The performance is examined in terms of throughput (bits/sec) and Response time of member servers in a load balancing pool. From these experiments we have observed that Ratio Model load balancing algorithm is most suitable in the environment of load balancing servers with different CPU usages as it allows assigning the weight according to CPU usage both in static and dynamic load balancing of servers.

Bonus : En jämförelse mellan fyra länder

Syftet med denna uppsats är att ge en bild av eventuella skillnader mellan fyra länder vad det gäller bonus till VD. Företagen som undersöks är ifrån Sverige, Storbritannien, USA och Norge. I uppsatsen redovisas teorier kring ersättningar och regelverk. Teorierna leder fram till tre stycken hypoteser som testas.Antal bolag från varje land som undersöks är 10 stycken, totalt 40 stycken. Bolagen har valts ut ifrån börslistor där de största bolagen från varje land finns med.Metoden som valts för undersökningen är en kvantitativ metod. Årsredovisningar och Proxy Statements undersöktes för att generera data.Undersökningen resulterar i att de två första hypoteserna styrks och den tredje kan inte få något stöd utifrån de material som undersöks. Som avslutning så ges förslag till vidare forskning inom ämnet.

An analysis of linkage between foreign direct investment and GDP per Capita in Pakistan : A time series analysis

This study aims to investigate the relation between foreign direct investment (FDI) and per capita gross domestic product (GDP) in Pakistan. The study is based on a basic Cobb-Douglas production function. Population over age 15 to 64 is used as a proxy for labor in the investigation. The other variables used are gross capital formation, technological gap and a dummy variable measuring among other things political stability. We find positive correlation between GDP per capita in Pakistan and two variables, FDI and population over age 15 to 64. The GDP gap (gap between GDP of USA and GDP of Pakistan) is negatively correlated with GDP per capita as expected. Political instability, economic crisis, wars and polarization in the society have no significant impact on GDP per capita in the long run.