Sampling error Essay Example

Sampling error Essay Research is defined as the creation of new knowledge and/or the use of existing knowledge in a new and creative way so as to generate new concepts, methodologies and understandings. This could include synthesis and analysis of previous research to the extent that it leads to new and creative outcomes.This definition of research is consistent with a broad notion of research and experimental development (Ramp;D) as comprising of creative work undertaken on a systematic basis in order to increase the stock of knowledge, including knowledge of humanity, culture and society, and the use of this stock of knowledge to devise new applications (OECD definition). This definition of research encompasses pure and strategic basic research, applied research and experimental development.Applied research is original investigation undertaken to acquire new knowledge but directed towards a specific, practical aim or objective (including a client-driven purpose). Research is an ORGANIZED and SYSTEMATIC way of FINDING ANSWERS to QUESTIONS. | | SYSTEMATIC because there is a definite set of procedures and steps which you will follow. There are certain things in the research process which are always done in order to get the most accurate results. ORGANIZED in that there is a structure or method in going about doing research. It is a planned procedure, not a spontaneous one. It is focused and limited to a specific scope.FINDING ANSWERS is the end of all research. Whether it is the answer to a hypothesis or even a simple question, research is successful when we find answers. Sometimes the answer is no, but it is still an answer. QUESTIONS are central to research. If there is no question, then the answer is of no use. Research is focused on relevant, useful, and important questions. Without a question, research has no focus, drive, or purpose. RESEARCH METHODS The research methodology defines what constitutes a research activity. It utilizes or is applicable to a model, and therefore sp ecifies concepts and related statements.The methodology identifies what methods to apply, how to measure progress and what constitutes success. It also specifies how to communicate about an area of research activity. TYPES OF RESEARCH METHODS 1. Historical-Qualitative – it is the systematic and objective location, evaluation and synthesis of evidence in order to establish facts and draw conclusions about past events. 2. Comparative-Qualitative – often used together with historical research to compare people’s experience of different societies, either between times in the past or in parallel situations in the present. It is conducted at a macro level or at a micro level. 3.Descriptive-Qualitative (Ethnography/Case Study) – this is a detailed description of specific situations using interviews, observations, document review. There is a description of things as they are. This works best for questions like How do people implement a program? What challenges do people face? What are the people’s perceptions? 4. Descriptive-Quantitative – This is a numerical description like frequency and average. We measure things as they are. Questions for this include How many people are participating in the program? What are the characteristics of the people in this program? How well did participants in this program do? . Correlational/Regression Analyses – It is a quantitative analysis of the strength of relationships between two or more variables 6. Quasi-Experimental – It involves the comparing of a group that gets a particular intervention with another group that is similar in characteristics but did not receive the intervention. 7. Experimental – this is the use of random assignment to assign participants to an experimental or treatment group and a control or comparison group. 8. Meta-analysis – This is a synthesis of results from multiple studies to determine the average impact of a similar intervention a cross studies 9.Evaluation – this is a descriptive type of research designed to deal with complex social issues. The outcomes do not represent â€Å"how things are† or â€Å"how they work†, rather they represent meaningful constructions which groups create to make sense of situations they find themselves in. evaluation should be action oriented, defines a course which can be practically followed and usually requires negotiation. 10. Action-oriented research – similar to experimental research although carried out in the real world ather than in the context of a closed experimental system – it involves small scale interventions in the functioning of the real world and a close examination of the effects of such an intervention. This is a practical form of research, aimed at a specific problem and situation and with little or no control over independent variables. 11. Ethnogenic – the aim of this research method is to represent a view of the wor ld as it is structures by the participants under observation by eliciting phenomenological data and this takes place in undisturbed natural settings of the subjects. LITERATURE REVIEWLiterature Review is an analysis of prior academic research so as to identify the who, what, where, and whys’ of the chosen topic area. It is a critical, analytical summary and synthesis of the current knowledge of a topic. Thus it should compare and relate different theories, findings, etc, rather than just summarize them individually. In addition, it should have a particular focus or theme to organize the review. It does not have to be an exhaustive account of everything published on the topic, but it should discuss all the significant academic literature important for that focus.TYPES OF LITERATURE REVIEW Traditional or Narrative literature Review * Critiques and summarizes a body of literature * Draws conclusions about the topic * Identifies gaps or inconsistencies in a body of knowledge * Re quires a sufficiently focused research question Weaknesses: * A large number of studies may make it difficult to draw conclusions * The process is subject to bias that supports the researchers own work. Systematic Literature Review * More rigorous and well-defined approach * Comprehensive Published and unpublished studies relating to a particular subject area * Details the time frame within which the literature was selected * Details the methods used to evaluate and synthesize findings of the studies in question SAMPLING Researchers use samples as a way to gather data in cases where it is almost impossible to gather the entire population as respondents. Moreover, if it is deemed too costly and too time consuming to include the entire populaiton, sampling is also necessary. A sample is a subset of the population being studied.It represents the larger population and is used to draw inferences about that population. It is a research technique widely used in the social sciences as a way to gather information about a population without having to measure the entire population. There are several different types and ways of choosing a sample from a population, from simple to complex. Non-probability Sampling Techniques Non-probability sampling is a sampling technique where the samples are gathered in a process that does not give all the individuals in the population equal chances of being selected.Reliance On Available Subjects. Relying on available subjects, such as stopping people on a street corner as they pass by, is one method of sampling, although it is extremely risky and comes with many cautions. This method, sometimes referred to as a convenience sample, does not allow the researcher to have any control over the representativeness of the sample. It is only justified if the researcher wants to study the characteristics of people passing by the street corner at a certain point in time or if other sampling methods are not possible.The researcher must also take c aution to not use results from a convenience sample to generalize to a wider population. Purposive or Judgmental Sample. A purposive, or judgmental, sample is one that is selected based on the knowledge of a population and the purpose of the study. For example, if a researcher is studying the nature of school spirit as exhibited at a school pep rally, he or she might interview people who did not appear to be caught up in the emotions of the crowd or students who did not attend the rally at all.In this case, the researcher is using a purposive sample because those being interviewed fit a specific purpose or description. Snowball Sample. A snowball sample is appropriate to use in research when the members of a population are difficult to locate, such as homeless individuals, migrant workers, or undocumented immigrants. A snowball sample is one in which the researcher collects data on the few members of the target population he or she can locate, then asks those individuals to provide information needed to locate other members of that population whom they know.For example, if a researcher wishes to interview undocumented immigrants from Mexico, he or she might interview a few undocumented individuals that he or she knows or can locate and would then rely on those subjects to help locate more undocumented individuals. This process continues until the researcher has all the interviews he or she needs or until all contacts have been exhausted. Quota Sample. A quota sample is one in which units are selected into a sample on the basis of pre-specified characteristics so that the total sample has the same distribution of characteristics assumed to exist in the population being studied.For example, if you a researcher conducting a national quota sample, you might need to know what proportion of the population is male and what proportion is female as well as what proportions of each gender fall into different age categories, race or ethnic categories, educational categor ies, etc. The researcher would then collect a sample with the same proportions as the national population. Probability Sampling Techniques Probability sampling is a sampling technique where the samples are gathered in a process that gives all the individuals in the population equal chances of being selected. Simple Random Sample.The simple random sample is the basic sampling method assumed in statistical methods and computations. To collect a simple random sample, each unit of the target population is assigned a number. A set of random numbers is then generated and the units having those numbers are included in the sample. For example, let’s say you have a population of 1,000 people and you wish to choose a simple random sample of 50 people. First, each person is numbered 1 through 1,000. Then, you generate a list of 50 random numbers (typically with a computer program) and those individuals assigned those numbers are the ones you include in the sample.Systematic Sample. In a systematic sample, the elements of the population are put into a list and then every kth element in the list is chosen (systematically) for inclusion in the sample. For example, if the population of study contained 2,000 students at a high school and the researcher wanted a sample of 100 students, the students would be put into list form and then every 20th student would be selected for inclusion in the sample. To ensure against any possible human bias in this method, the researcher should select the first individual at random. This is technically called a systematic sample with a random start.Stratified Sample. A stratified sample is a sampling technique in which the researcher divided the entire target population into different subgroups, or strata, and then randomly selects the final subjects proportionally from the different strata. This type of sampling is used when the researcher wants to highlight specific subgroups within the population. For example, to obtain a stratified sample of university students, the researcher would first organize the population by college class and then select appropriate numbers of freshmen, sophomores, juniors, and seniors.This ensures that the researcher has adequate amounts of subjects from each class in the final sample. Cluster Sample. Cluster sampling may be used when it is either impossible or impractical to compile an exhaustive list of the elements that make up the target population. Usually, however, the population elements are already grouped into subpopulations and lists of those subpopulations already exist or can be created. For example, let’s say the target population in a study was church members in the United States. There is no list of all church members in the country.The researcher could, however, create a list of churches in the United States, choose a sample of churches, and then obtain lists of members from those churches. References Babbie, E. (2001). The Practice of Social Research: 9th Editio n. Belmont, CA: Wadsworth Thomson. SLOVIN’S FORMULA When to Use Slovins Formula * If a sample is taken from a population, a formula must be used to take into account confidence levels and margins of error. When taking statistical samples, sometimes a lot is known about a population, sometimes a little and sometimes nothing at all.For example, we may know that a population is normally distributed (e. g. , for heights, weights or IQs), we may know that there is a bimodal distribution (as often happens with class grades in mathematics classes) or we may have no idea about how a population is going to behave (such as polling college students to get their opinions about quality of student life). Slovins formula is used when nothing about the behavior of a population is known at all. How to Use Slovins Formula * Slovins formula is written as: n = N / (1 + Ne^2) n = Number of samples N = Total population e = Error toleranceTo use the formula, first figure out what you want your erro r of tolerance to be. For example, you may be happy with a confidence level of 95 percent (giving a margin error of 0. 05), or you may require a tighter accuracy of a 98 percent confidence level (a margin of error of 0. 02). Plug your population size and required margin of error into the formula. The result will be the number of samples you need to take. For example, suppose that you have a group of 1,000 city government employees and you want to survey them to find out which tools are best suited to their jobs. You decide that you are happy with a margin of error of 0. 5. Using Slovins formula, you would be required to survey n = N / (1 + Ne^2) people: 1,000 / (1 + 1000 * 0. 05 * 0. 05) = 286 PLAGIARISM According to the Merriam-Webster Online Dictionary, to plagiarize means * to steal and pass off (the ideas or words of another) as ones own * to use (anothers production) without crediting the source * to commit literary theft * to present as new and original an idea or product deri ved from an existing source In other words, plagiarism is an act of fraud. It involves both stealing someone elses work and lying about it afterward Examples of plagiarism: turning in someone elses work as your own * copying words or ideas from someone else without giving credit * failing to put a quotation in quotation marks * giving incorrect information about the source of a quotation * changing words but copying the sentence structure of a source without giving credit * copying so many words or ideas from a source that it makes up the majority of your work, whether you give credit or not Belen, Other than these, review mo din ung statement of the problem mo, conceptual framework, paradigm at methodology dun sa pinasa mong research proposal before. Im sure itatanong un sa u.