White Noise Process Definition

The term white noise in economics is derivative of its meaning in mathematics and in acoustics. To understand the economic significance of white noise, its helpful to look at its mathematical definition first.   White Noise in Mathematics Youve very probably heard white noise, either in a physics lab or, perhaps, at a sound check. Its that constant rushing noise like a waterfall. At times you may imagine youre hearing voices or pitches, but they only last an instant and in reality, you soon realize, the sound never varies.   One math encyclopedia defines white noise as A generalized  stationary stochastic process  Ã‚  with constant  spectral density. At first glance, this seems less helpful than daunting. Breaking it down into its parts, however, can be illuminating.   What is a stationary stochastic process? Stochastic means random, so a stationary stochastic process is a process that is both random and never varying -- its always random in the same way. A stationary stochastic process with constant spectral density is, to consider an acoustic example, a random conglomeration of pitches -- every possible pitch, in fact -- which is always perfectly random, not favoring one pitch or pitch area over another.   In more mathematical terms, we say that the nature of the random distribution of pitches in white noise is that the probability of any one pitch is no greater or less than the probability of another. Thus, we can analyze white noise statistically, but we cant say with any certainty when a given pitch may occur.   White Noise in Economics in the Stock Market White noise in economics means exactly the same thing. White noise is a random collection of variables that are uncorrelated. The presence or absence of any given phenomenon has no causal relationship with any other phenomenon.    The prevalence of white noise in economics is often underestimated by investors, who often ascribe meaning to events that purport to be predictive when in reality they are uncorrelated. A brief perusal of web articles on the direction of the stock market will indicate each writers great confidence in the future direction of the market, beginning with what will happen tomorrow to long-range estimates.   In fact, many statistical studies of the stock markets have concluded that although the direction of the market may not be entirely random, its present and future directions are very weakly correlated, with, according to one famous study by future Nobel Laureate economist Eugene Fama, a correlation of less than 0.05. To use an analogy from acoustics, the distribution may not be white noise exactly, but more like a focused kind of noise called pink noise. In other instances related to market behavior, investors have what is nearly the opposite problem: they want statistically uncorrelated investments to diversify portfolios, but such uncorrelated investments are difficult, perhaps close to impossible to find as world markets become more and more interconnected. Traditionally, brokers recommend ideal portfolio percentages in domestic and foreign stocks, further diversification into stocks in large economies and small economies and different market sectors, but in the late 20th and early 21st centuries, asset classes that were supposed to have highly uncorrelated results have proven to be correlated after all.

Dire Predictions Global Warming Free Essays

Geography November 29, 2010 Dire Predictions : Student Edition Chapter one of Dire Predictions Understanding Global Warming does exactly like the title says, it gives the reader the essential basics of understanding the Global Warming issue. Chapter one gives essential information covering a wide range of things including: the natural and human impacts on climate, definition of a greenhouse gas and how it affects temperature, positive and negative feedback loops, threatening human byproducts that affect the ozone, ways scientists study ancient climates, and it gives possible future Earth outcomes due to global warming. It is a really loaded chapter I know, but this information proves to be very valuable when learning about global warming. We will write a custom essay sample on Dire Predictions: Global Warming or any similar topic only for you Order Now In fact, the information is so valuable that it can’t be covered by just stating a quick overview of the chapter, but needs a more detailed summary. Some natural variables that potentially affect the Earth’s climate include the sun, volcanic eruptions, and Earth’s orbit. But how exactly does something like a volcanic eruption effect climate? This is because â€Å"Explosive volcanic eruptions modify the composition of the atmosphere by injecting small particles called aerosols into the atmosphere layer. † These released aerosols block the solar radiation that would have reached Earth’s surface and consequently, it has cooling effect on Earth’s surface. The more talked about topic in chapter one however is the non-natural, or human induced impacts causing global warming. Humans burning of fossil fuels and release of chlorofluorocarbons (CFC’s) are both examples of human variables that affect global warming. CFC’s are a kind of gas that is released by cooling apparatus’ such as the refrigerator. These gasses have been proven to destroy the ozone. Furthermore, the book goes on to prove that the major impacts causing global warming are not natural but mostly human made. It states that the hole in the ozone is not mostly caused by a natural increase in CO2 gasses but the release of CFC-11 and CFC-12 gasses by humans into the environment. As proof of the gasses affect on the ozone it states that the average temperature of the globe has gone up from 13. degrees Celsius to 14. 5 degrees Celsius. It seems like a small amount of temperature increase but even one degree average increase can have a major influence on global warming. Finally, chapter one goes on to describe what happens if these patterns persist. So what will happen if these patterns persist, and what effects will it have on agriculture and man? To better understand what will happen to us, we have to understand what t he ozone layer does. The ozone layer protects us from harmful ultraviolet radiation. If these patterns persist the ozone will protect less and less ultraviolet radiation from entering Earth’s atmosphere. If this happens then the ice caps will melt which will be catastrophic to man and agriculture. According to http://www. tropical-rainforest-animals. com/Global-Warming-Effects. html some effects of global warming will be: Floods Droughts, Heat waves, Extreme winter cold and snow fall, Tornadoes, Extreme storms, Tropical cyclones, hurricanes, and typhoons. You don’t have to be a geography major to know that these types of effects will deal a devastating blow to people and plants. Precipitation patterns will also change everywhere, messing up normal agricultural growth. Some more effects global warming will have on agriculture and animals is it will make trees produce leaves earlier, it will cause earlier greening on vegetation, it causes re-distributions of algae that will kill animals that eat it to survive, and the ultraviolet radiation will ultimately poison humans and animals and destroy plants everywhere. If we have no ozone life will be unsustainable on Earth. But wait, all these horrible things don’t have to happen; we can do things to prevent global warming. We can start to help this not to happen by burning up less fossil fuels, thus reducing emissions into the ozone. Scientists and mechanics have recently been working together to make cars that produce less waste and are better for the environment. We can help by buying these kinds of cars and investing in this type of research. Another way to help is if we as a world unite and we set goals and laws that require fewer emissions from each country. Also, it may seem small but a way we can all help is by recycling things which cuts down the waste it takes to make whole new things. More ways you can help are by: using less air conditioning and heat, changing light bulbs to more energy efficient ones, buying energy efficient products, driving less or carpooling, using less hot water, and finally planting a tree. Although planting a tree or changing a light bulb may seem like a small way to help, if everyone in the world followed these suggestions emissions would be greatly reduced which could save the Earth. Scientists have worked together to try to understand the problem. By constantly recording new data and looking at old data they have come to a better understanding of what we use that causes these emissions and the way it affects us and our planet. A way scientists have studied the ancient atmosphere is by drilling into the ice caps and examining the trapped air. Also scientists are constantly observing the ozone layer to see any changes that might come. Scientists also look at what kind of molecules the ozone is made of and gasses that could destroy it. Learning about the problem is half the battle so we are on our way to a brighter tomorrow. I think the information given in the book was good information based on scientific truths. The information in this book was very easy to follow as almost every page had a corresponding graph or picture to help you understand the information given. However one of the problems I had with the information in this book is I felt that it was really quick to discredit the other side of the argument with not much detail. When faced with an opposing point the author just basically says that all other views are wrong and moves on. Also, the information in this book jumped to something completely different every other page. But that being said I did learn a lot from reading this book. The thing I found most interesting in the book were some of the statistics given throughout the chapter. For example thought how long the gasses CFC-11 and CFC-12 last and how much more potent it is that carbon dioxide. Even after five hundred years after CFC-12 is released, it is still 5,200 times more potent than carbon dioxide. And five hundred years after CFC-11 is released, it is 1,620 times more potent that the carbon dioxide (Dire Predictions, p. 9). With CFC gasses and other harmful gasses lasting this long it is important to stop the release of these harmful gasses as soon as we can. Another thing I found interesting in the book was the change in Mount Kilimanjaro snow coverage over time. First, it shows Mount Kilimanjaro during the year 1912 and it is covered in snow. That picture is followed by a picture of Mount Kilima njaro during the year 2007, and the snow cover has almost all disappeared. Another statistic I found very interesting in chapter one is the graphs on page thirty-three. These graphs show the amount of carbon dioxide, methane, and nitrous oxide in the atmosphere before and up to 2005. The graphs show that the levels of these greenhouse gasses are pretty constant until it reaches the year 2005; When the graph line representing the gasses reaches to just before the year 2005, levels of all three of these gasses skyrocket. (Dire Predictions, pg. 33) Reading this book made me realize how serious the global warming issue is and how it is already affecting the world today. Due to global warming life as we know it could possibly come to an end. But don’t start putting your bucket list together just yet. If we start doing things everyday to help reduce the emission of greenhouse gasses we can make sure that tomorrow is a brighter day, figuratively that is. The things stated earlier (using less air conditioning and heat, changing light bulbs to more energy efficient ones, buying energy efficient products, driving less or carpooling, using less hot water, planting trees) are all examples of everyday things we can do to help the environment and stop global warming. Another thing that people can do to help this problem is by educating themselves about global warming. By educating yourself about global warming you can solve the problem easier because you know the causes. Also you can educate other people about the importance of taking global warming into consideration. If everyone around the world pitches in to try to help, maybe the next book we read will be Optimistic Predictions. Works Cited Banerjee, Subhankar. â€Å"Global Warming. † New York Times. 6 Oct. 2010. Mann, Michael E. , and Lee R. Kump. Dire Predictions: Understanding Global Warming. New York, NY: DK Pub. , 2009. Print. May, Elizabeth, and Zoe? Caron. Global warming for dummies . Mississauga, ON: J. Wiley Sons Canada, 2009. Print. Nodvin, Stephen C. â€Å"Global Warming. † encyclopedia of earth. 9 May. 2010. 29 Nov. 2010. . Yeatman, William. â€Å"Global Warming: Solutions/Cost/Science GlobalWarming. org  |  Archive  |  Global Warming 101 . † Global Warming . N. p. , 9 Feb. 2009. Web. 29 Nov. 2010. . How to cite Dire Predictions: Global Warming, Papers

Television, What A Waste of Timme Essay Example For Students

Television, What A Waste of Timme Essay Television, What A Waste of TimmeHow much does television mean to you? Would you sacrifice your mind, yourhealth, and your well-being just to keep ahold of it? Most people would. Theyare unaware of the severe effects that TV has on our lives and on our future. Ithink that television should be banned from all American households because ofthe negative ideas it exploits, the creative minds it destroys, and the growingamount of kids and adults that are making this place a bigger and lazier country. In the last decade, the amount of vioilence on television has greatly increasedand so has the number of senseless homicides and suicides in our country. Thepromiscuity and violence shown regularly on household televisions has intriguesus as Americans and numbed our sense of whats right and whats wrong in society. What shocked us at first has now become customary dinner-time cinema. We will write a custom essay on Television, What A Waste of Timme specifically for you for only $16.38 $13.9/page Order now With the increase in the number of television sets in America, more and moreyoung people have been robbed of their creativity. With TV, hardly anything isleft to the imagination. Before the existence of television, all people wreforced to create their own opinions and images of things in their own minds. But with TV, all the images are created for you and almost all the arguments areone-sided. With TV, you no longer create your own ideas; you are told them. Television has a great impact on the health of America. The seductive topicsand biased broadcasts shows daily across America are luring more and more peopleto the confines of their living room couch for a greater amount of time. Inactivity and overeating are a common result of this decision made by adultsand kids alike. Perhaps this is the reason why America is one of the fattestcountries in the world. Television is slowly and subliminally taking its toll on America. It isstealing all of the things that are most precious to usour mind, body, andsoul. If you rely on television for all your entertainment, I think that youwould be way better off looking for it within yourself and the people around you.

Gender Issue in Legally Blonde Essays

Gender Issue in Legally Blonde Essays Gender Issue in Legally Blonde Essay Gender Issue in Legally Blonde Essay The document was written by an interviewer. 2. The document was written to give insight in the life of a slave woman. 3. The document is biased. The document is biased because Annie Coley was talking about slave life, but in the document she was only talking about her family’s life in slavery. (â€Å"We bought Sunday clothes. We got to rest three days at Christmas. We had a big dinner, but Boss gave us that out of his smokehouse. †) When Annie Coley says that, she is only referring to her own family during the slave days. She is not talking about slavery as a whole. 4. The document’s intended audience was basically the whole world; anybody who read it. 5. The document is an interview that was turned into an autobiography. 6. The document was written in the 1930’s. 7. The document was published in 1972. 8. The document focused on ex-slave Annie Coley’s life. 9. The document focused on the areas of freedom within the slave system, the situation of women in slavery, and the differences between slavery and freedom. 10. From the document I have learned that not all slave owners where terrible. I mean don’t get me wrong slavery in itself is horrible, but I mean in the way that the slaves where treated. For instance, when Annie Coley says (â€Å"After the crop was laid by, we went with Big Boss to his church and sat in the back seats. We couldn’t any of us read the Bible, so that was why Boss made us go to church so that we could hear it read. †) Although, the Boss should have let them go to school and learn how to read, he letting them hear the Bible being read in church was a gesture that he did care about them in some aspect. :

About the National Security Agency

About the National Security Agency The National Security Agency is a highly specialized and vital unit of the American intelligence community that works to create and break secret codes, a science known as cryptology. The National Security Agency, or NSA, reports to the U.S. Department of Defense. The work of the National Security Agency is done in secret and in the name of national security. The government did not even acknowledge the NSA existed for some time. The National Security Agencys nickname is No Such Agency. What the NSA Does The National Security Agency gathers intelligence by conducting surveillance on its adversaries through the collection of phone-call, email and Internet data. The intelligence agency has two primary missions: preventing foreign adversaries from stealing sensitive or classified national security information from the United States, and collecting, processing and disseminating information from foreign signals for counterintelligence purposes. History of the National Security Agency The National Security Agency was created on Nov. 4, 1952, by President Harry S. Truman. The intelligence agencys foundation has its genesis in the work U.S. forces conducted during World War II in breaking German and Japanese codes, which it describes as a crucial factor in the Allied success against German U-Boats in the North Atlantic and victory at the Battle of Midway in the Pacific. How the NSA is Difference From the FBI and CIA The Central Intelligence Agency deals mostly with gathering intelligence on Americas enemies and conducts covert operations overseas. The Federal Bureau of Investigation, on the other hand, operates within the U.S borders as a law-enforcement agency. The NSA is primarily a foreign intelligence agency, meaning that it is authorized to collect data to prevent threats from foreign countries. However, in 2013 it was revealed that the NSA and FBI had allegedly been collecting phone-call data from Verizon and other information from servers operated by none U.S. Internet companies including Microsoft, Yahoo, Google, Facebook, AOL, Skype, YouTube, and Apple. Leadership of the NSA The head of the National Security Agency/Central Security Service is appointed by the secretary of the Department of Defense and approved by the president. The NSA/CSS director must be a commissioned military officer who has earned at least three stars. The current director of the intelligence agency is U.S. Army Gen. Keith B. Alexander. The NSA and Civil Liberties The surveillance activities of the NSA and every other intelligence agency often raise questions about civil liberties, and whether Americans are being subjected to unconstitutional invasions of privacy. In a statement published on the NSAs website, agency deputy director John C. Inglis wrote: Im often asked the question, Whats more important – civil liberties or national security? Its a false question; its a false choice. At the end of the day, we must do both, and they are not irreconcilable. We have to find a way to ensure that we support the entirety of the Constitution – that was the intention of the framers of the Constitution, and thats what we do on a daily basis at the National Security Agency. Still, the NSA has publicly acknowledged that it has inadvertently collected communications from some Americans without a warrant in the name of national security. It has not said how often that happens, though. Who Oversees the NSA Foreign Intelligence Surveillance Court Government surveillance agencies are also subject to review by the Privacy and Civil Liberties Oversight Board, which was created by Congress in 2004.

Writer's choice Term Paper Example | Topics and Well Written Essays - 750 words

Writer's choice - Term Paper Example With the implementation of effective security mechanism we can gain a great deal of confidence and peace of mind while using these systems at home or marketplace (Shelly, Cashman and Vermaat; Turban, Leidner and McLean). This paper presents some of the security, privacy and ethical aspects regarding information technology and computer systems. There are many issues and threats which are hindering the successful operation and working on information and computer system arrangements. In this scenario, one of the initial risks is security issues from less effectively recruited staff personnel. For instance, any staff member with some illegal aims and objectives can set a virus in the database or hack the overall corporate information. Additionally, this is one of the major ethical dilemmas in information and computer systems (UN; Farshchi, Gharib and Ziyaee). In addition, differences in operating systems, versions and patches can also create various problems and issues regarding defense and protection of information and computer systems. In the absence of such protection strategy the overall information and data can be hacked or deleted. In worst case the business information can be accessed by corporate competitors. Additionally, absence of antivirus software for information and computer systems can also cause a huge problem for personal or business data and information. In case of such situation any virus can simply attack and destroy or stop the overall working of systems. In addition, one of the main issues is about the absence of internal firewalls. In this scenario, any user of systems and web services are open to virus attacks, malware, or Trojan attacks. In such situation overall information and computer systems can be hacked or influenced in case of effective handling and management of operations (UN; Farshchi, Gharib and Ziyaee ). This section discusses how some of the major and critical security, privacy and ethical issues happen.

Opportunity Cost Term Paper Example | Topics and Well Written Essays - 1750 words

Opportunity Cost - Term Paper Example   This is due to the fact that whereas the needs could be unlimited, the resources will always be scarce such that there is not one time when a person can afford to satisfy all his needs without sacrificing (Bloom 2004 p 26).   In this essay, various examples have been used to substantiate the definition of opportunity cost which is the value of the sacrificed alternative in favor of the decision or choice made.   It goes on to compare the relationship between scarcity and opportunity cost thereby showing that scarcity is the major factor that contributes to situations that result to households and firms undergoing opportunity cost.   The essay also continues to examine the environmental impacts that are not of financial nature but which exerts pressure on the choices and alternatives which are available. A case of oil mining has been used as an example that has both positive and negative impacts on the economy and the ecosystem respectively, factors that can create conflicts between the investor and the environmentalists. In some cases like this, it has been noted that the opportunity cost can be influenced by availing incentives so as to add weight to the importance of choosing an alternative over another. Further areas of research regarding opportunity cost have also been suggested in this essay.   Opportunity cost  Opportunity cost can be referred to as the foregone cost or a decision made over a range of alternatives favoring one of the alternatives.