Examples of Confidence intervals for means

One of the major parts of inferential statistics is the development of ways to calculate confidence intervals. Confidence intervals provide us with a way to estimate a population parameter. Rather than say that the parameter is equal to an exact value, we say that the parameter falls within a range of values.   This range of values is typically an estimate, along with a margin of error that we add and subtract from the estimate. Attached to every interval is a level of confidence. The level of confidence gives a measurement of how often, in the long run, the method used to obtain our confidence interval captures the true population parameter. It is helpful when learning about statistics to see some examples worked out. Below we will look at several examples of confidence intervals about a population mean. We will see that the method we use to construct a confidence interval about a mean depends on further information about our population. Specifically, the approach that we take depends on whether or not we know the population standard deviation or not. Statement of Problems We start with a simple random sample of 25 a particular species of newts and measure their tails. The mean tail length of our sample is 5 cm. If we know that 0.2 cm is the standard deviation of the tail lengths of all newts in the population, then what is a 90% confidence interval for the mean tail length of all newts in the population?If we know that 0.2 cm is the standard deviation of the tail lengths of all newts in the population, then what is a 95% confidence interval for the mean tail length of all newts in the population?If we find that that 0.2 cm is the standard deviation of the tail lengths of the newts in our sample the population, then what is a 90% confidence interval for the mean tail length of all newts in the population?If we find that that 0.2 cm is the standard deviation of the tail lengths of the newts in our sample the population, then what is a 95% confidence interval for the mean tail length of all newts in the population? Discussion of the Problems We begin by analyzing each of these problems. In the first two problems we know the value of the population standard deviation. The difference between these two problems is that the level of confidence is greater in #2 than what it is for #1. In the second two problems the population standard deviation is unknown. For these two problems we will estimate this parameter with the sample standard deviation. As we saw in the first two problems, here we also have different levels of confidence. Solutions We will calculate solutions for each of the above problems. Since we know the population standard deviation, we will use a table of z-scores. The value of z that corresponds to a 90% confidence interval is 1.645. By using the formula for the margin of error we have a confidence interval of 5 – 1.645(0.2/5) to 5 1.645(0.2/5). (The 5 in the denominator here is because we have taken the square root of 25). After carrying out the arithmetic we have 4.934 cm to 5.066 cm as a confidence interval for the population mean.Since we know the population standard deviation, we will use a table of z-scores. The value of z that corresponds to a 95% confidence interval is 1.96. By using the formula for the margin of error we have a confidence interval of 5 – 1.96(0.2/5) to 5 1.96(0.2/5). After carrying out the arithmetic we have 4.922 cm to 5.078 cm as a confidence interval for the population mean.Here we do not know the population standard deviation, only the sample standard deviation. Thus we will use a table of t-scores. When we use a tabl e of t scores we need to know how many degrees of freedom we have. In this case there are 24 degrees of freedom, which is one less than sample size of 25. The value of t that corresponds to a 90% confidence interval is 1.71. By using the formula for the margin of error we have a confidence interval of 5 – 1.71(0.2/5) to 5 1.71(0.2/5). After carrying out the arithmetic we have 4.932 cm to 5.068 cm as a confidence interval for the population mean.Here we do not know the population standard deviation, only the sample standard deviation. Thus we will again use a table of t-scores. There are 24 degrees of freedom, which is one less than sample size of 25. The value of t that corresponds to a 95% confidence interval is 2.06. By using the formula for the margin of error we have a confidence interval of 5 – 2.06(0.2/5) to 5 2.06(0.2/5). After carrying out the arithmetic we have 4.912 cm to 5.082 cm as a confidence interval for the population mean. Discussion of the Solutions There are a few things to note in comparing these solutions. The first is that in each case as our level of confidence increased, the greater the value of z or t that we ended up with. The reason for this is that in order to be more confident that we did indeed capture the population mean in our confidence interval, we need a wider interval. The other feature to note is that for a particular confidence interval, those that use t are wider than those with z. The reason for this is that a t distribution has greater variability in its tails than a standard normal distribution. The key to correct solutions of these types of problems is that if we know the population standard deviation we use a table of z-scores. If we do not know the population standard deviation then we use a table of t scores.

Definition of the Pendleton Act - 19th Century History

The Pendleton Act was a law passed by Congress, and signed by President Chester A. Arthur in January 1883, which reformed the federal government’s civil service system. A persistent problem, going back to the earliest days of the United States, had been the dispensing of federal jobs. Thomas Jefferson, in the earliest years of the 19th century, replaced some Federalists, who had attained their government jobs during the administrations of George Washington and John Adams, with people more closely aligned to his own  political views. Such replacements of government officials increasingly became standard practice under what became known as the Spoils System. In the era of Andrew Jackson, jobs in the federal government were routinely given to political supporters. And changes in administration could bring about widespread changes in federal personnel. This  system of political patronage became entrenched, and as the government grew, the practice eventually became a major problem. By the time of the Civil War, it was widely accepted that work for a political party entitled someone to a job on the public payroll. And there were often widespread reports of bribes being given to obtain jobs, and jobs being awarded to friends of politicians essentially as indirect bribes. President Abraham Lincoln routinely complained about office seekers who made demands on his time. A movement to reform the system of dispensing jobs began in the years following the Civil War, and some progress was made in the 1870s. However, the 1881 assassination of President James Garfield by a frustrated office seeker put the entire system into the spotlight and intensified calls for reform. Drafting of the Pendleton Act The Pendleton Civil Service Reform Act was named for its primary sponsor, Senator George Pendleton, a Democrat from Ohio. But it was primarily written by a noted attorney and crusader for civil service reform, Dorman Bridgman Eaton (1823-1899). During the administration of Ulysses S. Grant, Eaton had been the head of the first civil service commission, which was intended to curb abuses and regulate the civil service. But the commission was not very effective. And when Congress cut off its funds in 1875, after only a few years of operation, its purpose was thwarted. In the 1870s Eaton had visited Britain and studied its civil service system. He returned to America and published a book about the British system which argued that Americans adopt many of the same practices. Garfield’s Assassination and Its Influence on the Law Presidents for decades had been annoyed by office-seekers. For instance, so many people looking for government jobs visited the White House during the administration of Abraham Lincoln that he built a special hallway he could use to avoid encountering them. And there are many stories about Lincoln complaining that he had to spend so much of his time, even at the height of the Civil War, dealing with people who traveled to Washington specifically to lobby for jobs. The situation got far more serious in 1881, when newly inaugurated President James Garfield was stalked by Charles Guiteau, who had been rebuffed after aggressively seeking a government job. Guiteau had even been ejected from the White House at one point when his attempts to lobby Garfield for a job became too aggressive. Guiteau, who appeared to suffer from mental illness, eventually approached Garfield in a Washington train station. He pulled out a revolver and shot the president in the back. The shooting of Garfield, which would eventually prove fatal, shocked the nation, of course. It was the second time in 20 years that a president had been murdered. And what seemed particularly outrageous was the idea that Guiteau had been motivated, at least in part, by his frustration at not obtaining a coveted job through the patronage system. The idea that the federal government had to eliminate the nuisance, and potential danger, of political office-seekers became an urgent matter. The Civil Service Reformed Proposals such as those put forward by Dorman Eaton were suddenly taken much more seriously. Under Eaton’s proposals, the civil service would award jobs based on merit examinations, and a civil service commission would oversee the process. The new law, essentially as drafted by Eaton, passed the Congress and was signed by President Chester Alan Arthur on January 16, 1883. Arthur appointed Eaton as the first chairman of the three-man Civil Service Commission, and he served in that post until he resigned in 1886. One unexpected feature of the new law was President Arthurs involvement with it. Prior to running for vice president on the ticket with Garfield in 1880, Arthur had never run for public office. Yet he had held political jobs for decades, obtained through the patronage system in his native New York. So a product of the patronage system took a major role in seeking to end it. The role played by Dorman Eaton was highly unusual: he was an advocate for civil service reform, drafted the law pertaining to it, and was ultimately given the job of seeing to its enforcement. The new law originally affected about 10 percent of the federal workforce, and had no impact on state and local offices. But over time the Pendleton Act, as it became known, was expanded a number of times to cover more federal workers. And the success of the measure at the federal level also inspired reforms by state and city governments.

The Unexplained Mystery Into How to Start an Essay about Myself

The Unexplained Mystery Into How to Start an Essay about Myself College essay hooks can be challenging to generate, especially when you're still working on clarifying what your essay is likely to say. If you've already graduated from college or university and are looking for a fantastic job, you will need to get a persuasive resume to impress your future employer. You can tips essay as a result of your respect to other individuals. You're going to be surrounded by writing professionals throughout the plan of order placement, and once you opt to purchase essay and pick an allocated writer, things will get even more exciting. Sometimes, lots of people find them overwhelming but should you break the writing process into small components and attempt to finish your draft step-by-step, you can expect you are going to feel more confident and work more productively. Hence, understanding how to begin an essay with a quote is a significant skill that permits students to produce the best of their written assignments or speeches. The truth is that writing about a topic where there's a great deal of information can present issues for the writer, particularly when they're attempting to compose the introductory part. Your objective is to persuade the audience your text is worth reading. The procedure for producing a worthwhile describing myself essay can be challenging, not least because there's normally a good deal to say. Think of rough chapter titles and choose wherever your information ought to be placed. What all you will need is getting the assistance from a specialist and EssaysChief is going to be the expert that you seek out. Begin an essay usually intends to offer effective solutions to some problems, the great idea is to begin with advice. There are a lot of things to consider and most importantly, is the dependability of the service you decide to use. Tell our experts what kind of homework help on the internet you want to get. What How to Start an Essay about Myself Is - and What it Is Not Supply an intriguing fact about something you're likely to go over in your essay's body and your audience may wish to keep reading if you want to discover more. Otherwise, it is going to be something which distracts the readers' interest. If you are in possession of a good idea and you wish to be straightforward and intro duce it immediately as it's unique, do what you would like. What is 1 word or idea which you would use to describe yourself. Understand who you're writing for. Writing is a present that comes naturally. Writing quality essays is the principal purpose of our services. Writing a critical essay necessitates training and experience, but the most significant issue is it requires observation. Very good hooks could include contradictions. There's nothing more hooking that a question that interests a lot of individuals. If you get a good idea and hook are interested in being straightforward and introduce it immediately because it's unique, do what you would like. If you're in possession of a very good idea and you want to be straightforward and introduce it immediately because it's unique, do what you would love. The Argument About How to Start an Essay about Myself When starting a paragraph with a quote, make certain you stick to many essential rules. An academic article alway s must be relevant. Keep in mind, your article should be cohesive, and a great draft will help you in achieving it. In fact, prior to making an order you'll be able to find a price quote on your essay. The One Thing to Do for How to Start an Essay about Myself A terrific hook is the one which has many unique applications in 1 text. The duration of a conclusion is dependent upon the duration of your paper and its complexity and there's no any established formula how to do it right. Provide context to each quotation that you're using. A great quotation may be the most intensive sentence in your entire paper, thus, it may be wiser to avoid using it as the exact first sentence and rather, putting it aside for as soon as the momentum would reach its greatest value. Make certain it relates to the major idea of the paper. Otherwise, it's a pure plagiarism. It's going to be so much simpler to write, once you've finished your paper. The type of scientific paper I'm discussing her e is referred to as a principal research article. Your essay must incorporate all info required to understand your story. If this is the case, you might want to understand what an expository essay is. How a crucial essay needs to be written. For a personal essay, it's always preferable to describe the essay that is wholly unique and not every man or woman can go through it. The important thing is to make sure you clearly show the method by which the quote is related to your essay. A quote can frequently be perceived as such. The appropriate quotes may lead to your essay noticeably.

Investment in Ecotourism

Question: Explain, Should more be invested to promote ecotourism? Answer: Ecotourism is the well-known form of tourism that involves visiting fragile, pristine and peaceful natural areas. The ecotourism can be placed as the small-scale alternative to the standard commercial tourism. There are several benefits of ecotourism in both environmental, social as well as the economic aspect. It helps to educate travelers, provide funds for ecological conservation, economic development and political empowerment of local communities. Environmentalists have considered Ecotourism as a significant effort since the 1980s (Bulbeck 2012). Thus, governments should invest more on ecotourism to ensure that future generations would be able to experience destinations, free of disturbing human interventions. The strategic partnership is required for sustainable management of the ecotourism related initiatives and developments. For the huge scale of maintenance, high amount of investment is required for promoting ecotourism in different parts of the world (Lu and Stepchenkova 20 12). Therefore, it can be said that more investment is required for promoting ecotourism and sustainability. However, regulation strategies are very important. The main arguments include the proses and positive impact of eco-tourism on environment and economy. A number of initiatives has been taken, but there are huge number of opportunities where more investment can promote sustainable ecotourism projects. Lu and Stepchenkova (2012) argued that, nowadays ecotourism projects impose negative impact upon enviornment and wildlife. Thus, more investment is not needed in this field. However, there are some benefits of eco-tourism, which are attracting private investors to invest more in the ecotourism related initiatives. As eco-tourism provides the wide range of benefits, thus, investments can be enhanced for enhancing these benefits. One significant benefit of ecotourism is the biodiversity conservation. In 2005, the US Foundation grants for the environment, animals and wildlife were estimated t be approximate $US 1.04 billion. On the other hand, Tourism Satellite Accounting research spent more than $US 6 trillion on travel and tourism (Jaafar and Maideen 2012). From this huge amount of investment, it can be argued that the investors have found something promising from ecotourism, which can be enhanced with more investment. Ecotourism offers investors both conservation and a development st rategy. However, it has also been claimed by Jalani (2012) that without applying the universally accepted standards, ecotourism can be over-used and have negative social and ecological impacts. In this context, ecotourism can hamper the achievement of community and environment development and sustainability funding objectives. Therefore, ecotourism projects should be planned with a sustainable strategy to attract investors. Sukserm et al. (2012) has argued the dominated group of investors including the international lending agencies is pumping millions of dollars into their ecotourism related projects under the banner of sustainable rural development, biodiversity improvement, local income generation, infrastructure development and institutional capacity building. It has been reported that after 2001, funding for ecotourism and sustainable tourism began to decline, as it was difficult to support the sustainable development through the ecotourism projects. This decline made the investment relatively risky in this field. The risk was caused due to the inherent finance challenges in the ecotourism model. Most common issues include the fragmented nature of tourism projects and related lack of market data. However, the huge investment in 2005 for ecotourism projects ensured this niche field as one of the fastest growing sectors or the travel industry that is expanding three times faster than the entire globa l tourism industry. U.S. grantmaking foundations provided this report, which helps to represent the benefits of funding in ecotourism industry and its sustainability. Researchers have found that within 2001-2010, minimum US$9.43 billion have been poured into 363 ecotourism projects around the world (Hammerschlag et al. 2012). It has been found that there are different sources of funding for ecotourism, bilateral donors, multilateral donors, corporate philanthropy, internationals foundations, big international NGOs and development banks. These investors should undertake in depth research in this field and then should think about more investment. Chaminuka et al. (2012) claimed that, ecotourism has been shown as a potential economic and environmental savior in Latin America. However, it was argued that the explosive foreign investment in eco-tourism projects raised a significant question regarding the validity of sustainable development related to ecotourism. It is evident that in some cases, it has been seen that ecotourism projects are putting stress on wildlife and the local population, in the absence of proper regulation and management. Another major counter argument is that ecotourism often converts the local economy to a tourist economy, by damaging the natural economic prospects of the local area for serving wealthy foreigners (Miller 2012). However, it is the most common way for small investors to gain huge profit from this industry. It can destroy local industry and agriculture by reducing workers attraction from the industry, thereby leading to an economic downturn. These kinds of activities can make the local econo my to be dependent on foreign funds. In this situation, investment by the local investor is very important and can be more profitable. In Costa Rica, ecotourism can be promoted through the utilization of the natural resources, it has been seen that the ecotourism initiatives lack proper regulation and sustainability activities. Instead, the previous reports, it has been observed that promotion of ecotourism in Costa Rica had a significant positive impact on the environment and economy. Through years, ecotourism has become one of the main justifications for the preservation of natural areas throughout Costa Rica. It resulted in rapid expansion of national park system including seventy entities. The promotion of ecotourism in Costa Rica made it the leading country in environmental preservation throughout the Caribbean. In addition, Mohammadi et al. (2012) claimed that emphasis on natural preservation for ecotourism purposes promoted the reduction of wide spread deforestation of the countryside. From different aspects, ecotourism is an advantageous model for achieving the environmental prosperity and sustainability. Ho wever, in Costa Rica, there is a wide range of opportunities through which the ecotourism model can be improved. In this context, it can be said that better management and regulation can help to enhance the sustainability of ecotourism initiatives. For better regulation and management, increased funding is required. In the case of ecotourism in Costa Rica, for better management practices, better implementation, monitoring and evaluation is required, which require more human and financial resources (Fletcher and Neves 2012). Therefore, more investment can help to resolve these issues. The government needs to develop more creative ways for generating income. It will help in the maintenance of park system as well as for the training of park rangers and staffs, which would make them more efficient in managing park related issues. Therefore, from this discussion, it can be interpreted that more investment can promote the positive sides of ecotourism initiatives, which can help to enhance both environmental and economic benefits. There are some areas having a wide range of opportunities for ecotourism projects. Queensland is such a place having the natural competitive advantage in providing visitors with high quality ecotourism experiences due to the presence of excellent national parks and marine parks. However, promotion of ecotourism in Queensland also has some significant cons, regarding price, authenticity, reliability and communication, all of which needs strict monitoring and evaluation. Instead, the proses are higher. Queensland has five world heritage areas among the 19 such areas in Australia, such as Great Barrier Reef. Promoting investment would help to double visitors expenditure to$30 billion by 2020 (Jalani 2012). According to the report of Miller (2012),Queensland needs to build on competitive advantage for investing in new ecotourism products and experiences. Through the implementation of attractive investment model and probity, the government can attract private investors. Now the question i s what is the way to achieve quality investment in ecotourism? Strategic planning can give the best answer. Creating positive business environment can ensure the investors the high amount of investment return (Jalani 2012). Therefore, it can be said that promoting more investment in Queensland can enhance the ecotourism related benefits. In the previous paragraphs, all the discussion was done for analyzing the feasibility of promoting investment in ecotourism. From the discussion, both the pros and cons of investment in ecotourism have been derived. It has been revealed from the arguments and statements that, ecotourism is one of the fastest growing industries throughout the world, a huge amount of money has been invested in this field, however, due to lack of maintenance, and some quality related issues, investments have been decreased. Nevertheless, there are some areas throughout the world, where ecotourism projects have some attractive opportunities. Once these opportunities are exploited, both sustainable environmental and economic benefits will be achieved. Therefore, it can be interpreted that with strategic management and proper regulation, more investment can promote ecotourism. Reference List Bulbeck, C., 2012.Facing the Wild:" Ecotourism, Conservation and Animal Encounters". Routledge. Chaminuka, P., Groeneveld, R.A., Selomane, A.O. and Van Ierland, E.C., 2012. Tourist preferences for ecotourism in rural communities adjacent to Kruger National Park: A choice experiment approach.Tourism Management,33(1 Fletcher, R. and Neves, K., 2012. Contradictions in tourism: The promise and pitfalls of ecotourism as a manifold capitalist fix.Environment and Society: Advances in Research,3(1), pp.60-77. Hammerschlag, N., Gallagher, A.J., Wester, J., Luo, J. and Ault, J.S., 2012. Dont bite the hand that feeds: assessing ecological impacts of provisioning ecotourism on an apex marine predator.Functional Ecology,26(3), pp.567-576. Jaafar, M. and Maideen, S.A., 2012. Ecotourism-related products and activities, and the economic sustainability of small and medium island chalets.Tourism Management,33(3), pp.683-691. Jalani, J.O., 2012. Local people's perception on the impacts and importance of ecotourism in Sabang, Palawan, Philippines.Procedia-Social and Behavioral Sciences,57, pp.247-254. Lu, W. and Stepchenkova, S., 2012. Ecotourism experiences reported online: Classification of satisfaction attributes.Tourism Management,33(3), pp.702-712. Miller, A.P., 2012.Ecotourism development in Costa Rica: the search for Oro Verde. Lexington Books.), pp.168-176. Mohammadi, J., Ahmadi, D. and Godarzi, M., 2012. An analysis Seydan ecotourism with emphasis on sustainable development.Management Science Letters,2(6), pp.2019-2024. Sukserm, T., Thiengkamol, N. and Thiengkamol, T., 2012. Development of the Ecotourism Management Model for Forest Park.Journal of the Social Sciences,7(1), pp.95-99.