wiktionarypar samplingSampling may refer to Sampling signal processing , converting a continuous signal into a discrete signal Sample graphics Sampling graphics , converting continuous colors into discrete color components Sampling music , re using portions of sound recordings in a piece Sampler musical instrument , an electronic music instrument that plays back sound recordings on command Sampling statistics , selection of observations to acquire some knowledge of a statistical population Sampling case studies , selection of cases for single or multiple case studies Sampling audit , application of audit procedures to less than 100 of population to be audited Sampling for testing or analysis , taking a representative portion of a material or product to test e.g. by physical measurements, chemical analysis, microbiological examination , typically for the purposes of identification, quality control, or regulatory assessment Specific types of sampling include Chorionic villus sampling , a method of detecting fetal abnormalities Food sampling , the process of taking a representative portion of a food for analysis, usually to test for quality, safety or compositional compliance. Not to be confused with free sample Food, free samples , a method of promoting food items to consumers Oil sampling , the process of collecting samples of oil from machinery for analysis Theoretical sampling , the process of selecting comparison cases or sites in qualitative research Water sampling , the process of taking a portion of water for analysis or other testing, e.g. drinking water to check that it complies .... Work sampling , a method of estimating the standard time for manufacturing operations. See also Sample disambiguation Sampler disambiguation disambig ca Mostreig cs Vzorkov n rozcestn k de Sampling es Muestreo fa fr chantillonnage ko it Campionamento he no Sampling pt Amostragem pl Pr bkowanie ru simple Sampling sv Sampling ... more details
Continuous auditing is the application of automated tools to provide Assurance services assurance on financial and non financial data within a company. Simply put, continuous auditing uses a set of tools ... to prevent errors and fraud. The continuous aspect of continuous auditing and reporting ... auditing has its own pulse. The internal management chooses for evaluation depends on the frequency ... hourly, daily, weekly, monthly, etc. depending on the application. History of continuous auditing The first application of continuous auditing was developed at AT&T Bell Laboratories in 1989 ref Vasarhelyi, M.A. and Halper, F. B., 1991, The Continuous Audit of Online Systems, Auditing A Journal of Practice and Theory, 10 1 , 110 125. ref . Known as a continuous process auditing system CPAS , the system ... information were also introduced. Components of continuous auditing Continuous auditing is made ... Data Assurance A concern with continuous auditing is that the financial information is correct ... of auditors. The objective of black box logging is to protect a continuous auditing system ... strategic moves and undermine competitive advantage. Demand Demand for continuous auditing has come .... Working paper presented at the Fifth Continuous Auditing Symposium. ref . Internal drivers As companies ... is also driving demand for continuous auditing ref Van Decker, J., 2004, The Need for Continuous ... to achieve a specific goal. By these laws and regulation company comenced for continuous auditing. Technology XBRL XBRL facilitates the development of continuous auditing modules by providing ... of the information passing through continuous auditing systems, security and privacy issues are also ... test these controls. Comparison to Computer Aided Auditing Continuous auditing is often confused with computer aided auditing. The purpose and scope of the two techniques, however, are quite different. Computer aided auditing employs end user technology including spreadsheet software, such as Microsoft ... more details
Unreferenced date December 2009 Orphan date December 2009 Data Auditing is the process of conducting a data audit to assess how fit for purpose a company s data is. This involves data profiling profiling the data and assessing the impact of data quality poor quality data on the organization s performance and profits. DEFAULTSORT Data Auditing Category Data management Category Data quality Tech stub ... more details
Refimprove date April 2010 Auditing was developed by L. Ron Hubbard , and is described by the Church of Scientology as spiritual counseling which is the central practice of Dianetics and Scientology . Description Auditing in the context of Dianetics and Scientology is an activity where a person trained in auditing listens and gives auditing commands to a subject, which Scientologists refer to as a preclear . Citation needed date November 2008 Critics of auditing have suggested that it has similarities with cult style programming and some behavior modification techniques which result in psychological ... communications during auditing are confidential. Auditing involves the use of processes, which are sets ... of everything that happens and becomes even more alert as auditing progresses. Citation needed date ... toward the preclear called the Auditor s Code. Citation needed date November 2008 Auditing is said ... ref http www.scientology.org en US religion auditing pg004a.html website Scientology.org THE AUDITOR ... File Scientology e meter blue.jpg thumb Mark Super VII Quantum E meter Most auditing sessions employ ... during auditing. These low Electric potential potential changes in electrical resistance are believed ... and even trillions of years. Controversy Preclear folders The Scientology Dianetics auditing process has raised concerns from a number of quarters, as auditing sessions are permanently recorded in the form ... through auditing leaves an adherent vulnerable to potential blackmail should they ever consider ... , found that auditing involved a form of authoritative or command hypnosis , in which the hypnotist ... have claimed benefits from auditing including improved IQ , improved ability to communicate ... studies have verified these claims. Indeed, the aforementioned Anderson report stated that auditing ... states. Licensed psychotherapists have alleged that the Church s auditing sessions amount ... Free Zone E Meters Scientology Category Scientology beliefs and practices Auditing it Auditing Scientology ... more details
Multiple issues orphan February 2009 refimprove October 2006 According to the National Association of Legal Auditing NALA , legal auditing is a litigation management practice and risk management tool, used by insurance and other consumers of legal services, to determine if hourly billing errors, abuses, and inefficiencies exist by carefully examining and indentifying unreasonable Lawyer attorney fees and expenses. ref http www.thenalfa.org National Association of Legal Fee Analysis Bot generated title ref Methods Legal auditors conduct a detailed analysis of original time records, attorney work production, expenses and hourly rate benchmarks. The purpose of a legal bill auditing is to save money for the insurance company and their clients. Many audits measure performance and quality of services in addition to cost alone. Legal Bill Auditors may be responsible for monitoring the matter as it progresses for purposes of giving a second opinion in major cases or as a post mortem. Legal bill audits give insurance companies and their clients peace of mind and avoid possible future mistakes. Citation needed date February 2008 Recently, the firm Stuart Maue ref http www.smmj.com Stuart Maue ref claimed to have conducted the largest legal audit on record during the OxyContin litigation, involving claims for attorney fees and expenses amounting to over 400,000,000 billed and audited, with the final negotiated Settlement law settlement resulting in a reduction of 200,000,000 from the total billed amount. ref http stlouis.bizjournals.com stlouis stories 2006 07 03 daily22.html Stuart Maue completes audit on 400M claim St. Louis Business Journal Bot generated title ref Notes references DEFAULTSORT Legal Auditing Category Auditing ... more details
Materiality is a concept or convention within auditing and accounting relating to the importance significance of an amount, transaction, or discrepancy. The objective of an audit of financial statement s is to enable the auditor to Auditor s report express an opinion whether the financial statement s are prepared, in all material respects, in conformity with an identified financial reporting framework such as Generally Accepted Accounting Principles GAAP . The assessment of what is material is a matter of professional judgment. Information is material if its omission or misstatement could influence the economics economic Decision theory decision of users taken on the basis of the financial statements. Materiality depends on the size of the item or error judged in the particular circumstances of its omission or misstatement. Thus, materiality provides a threshold or cut off point rather than being a primary qualitative characteristic which information must have if it is to be useful. The Financial Accounting Standards Board FASB has refrained from giving quantitative guidelines for determining materiality. This has resulted in confusion in the use of Auditing Standards No 47, Audit Risk and Materiality in Conducting the Audit . Several common rules that have appeared in practice and academia .... Two different auditors auditing even the same entity might generate differing scopes of audit .... Materiality in governmental auditing Materiality in governmental auditing is different from materiality in private sector auditing for several reasons. The typical scope of audits in the private sector ... of materiality in governmental auditing is different from materiality in other audits, because the definition .... In government auditing, the political sensitivity to adverse media exposure often concerns ... auditing than in private sector auditing. Qualitative materiality refers to the nature of a transaction ... Auditing zh ... more details
confusing date April 2009 nofootnotes date April 2009 wikify date April 2009 Cleanup date March 2009 Public auditing is examination of the records and reports of an enterprise or departments of government by specialists or the person appointed by the government eg Comptroller and Auditor General of India other than those responsible for their preparation. The public accountant performs tests to determine whether the management s statements were prepared in accord with generally accepted accounting principles and fairly present the firm s financial position and operating results such independent evaluations of management reports are of interest to actual and prospective shareholders, bankers, suppliers, lessors, and government agencies. The public expect that those responsible for handling public money are held fully accountable for the use of that money. The prime responsibility for ensuring that public money is handled with absolute integrity and spent wisely, rests with Ministers, elected members, governing bodies, managers and officials. Public audit is an important link in that chain of accountability. It strengthens accountability, both upwards to the elected or appointed members who provide resources, and outwards to the consumers and beneficiaries, taxpayers and the wider community at large The Principles of Public Audit the independence of public sector auditors from the organizations being audited the wide scope of public audit, that is covering the audit of financial statements, regularity or legality , propriety or probity and value for money and the ability of public auditors to make the results of their audits available to the public, and to democratically elected representatives. Category Auditing ... more details
sampling theory may mean Nyquist Shannon sampling theorem , digital signal processing DSP Statistical sampling Fourier sampling mathdab ... more details
Unreferenced date July 2007 In audit ing, sampling is an inevitable means of testing. However, sampling is always associated with sampling risks which auditors have to control. Sampling risk represents the possibility that auditor s conclusion based on a sample is different from that reached if the entire population were subject to audit procedure. The auditor may conclude that material misstatements exist, in fact they do not or material misstatements do not exist but in fact they do exist. Auditor can lower the sampling risk by increasing the Sample size sampling size . Non sampling risk includes factors that cause auditors to reach a conclusion other than the sampling size. Interpreting Misinterpretation of evidence and inappropriate Procedure term procedures are good examples. Changing of the sampling size would not reduce non sampling risk. See also Sample statistics DEFAULTSORT Sampling Risk Category Sampling statistics Category Actuarial science Category Risk ... more details
In the theory of finite population sampling , Bernoulli sampling is a sampling process where each element of the statistical population population that is sampled is subjected to an statistical independence independent Bernoulli trial which determines whether the element becomes part of the sample during the drawing of a single sample. An essential property of Bernoulli sampling is that all elements of the population have equal probability of being included in the sample during the drawing of a single sample. Bernoulli sampling is therefore a special case of Poisson sampling , where each element of the population may have a different probability of being included in the sample. Because each element of the population is considered separately for the sample, the sample size is not fixed but rather follows a binomial distribution . See also Poisson sampling Bernoulli trial Bernoulli process Sampling design Further reading Sarndal, Swenson, and Wretman 1992 , Model Assisted Survey Sampling, Springer Verlag, ISBN 0 387 40620 4 Category Sampling statistics Category Sampling techniques ... more details
During sampling of Particulate matter particulate materials , correct sampling is defined in Gy s sampling theory as a sampling scenario in which all particles in a population have the same probability of ending up in the sample ref name Gy1979 P. M. Gy 1979 , Sampling of Particulate Materials theory and practice. Elsevier Amsterdam, 431 pp. ref . The concentration of the property of interest in a sample can be a Bias statistics biased estimate, for the concentration of the property of interest in the population from which the sample is drawn. Although generally non zero, for correct sampling this bias is thought to be negligible ref name Gy1979 ref . See also Particulate matter sampler Statistical sampling Gy s sampling theory References Reflist Category Sampling statistics Category Particulates Category Meteorological instrumentation and equipment statistics stub ... more details
In sampling theory , sampling fraction is the ratio of sample size to population size or, in the context of stratified sampling , the ratio of the sample size to the size of the stratum. ref cite book last Dodge first Yadolah title The Oxford Dictionary of Statistical Terms publisher Oxford University Press location Oxford date 2003 isbn 0 19 920613 9 language English ref The formula for the sampling fraction is n N , where n is the sample size and N is the population size. If the sampling fraction is less than 5 , then the finite population effect might be ignored. References references Statistics stub Category Sampling statistics Category Statistical ratios ... more details
Refimprove date October 2009 sampling statistics Sampling is the use of a subset of the population statistics population to represent the whole population. Probability sampling, or random sampling , is a sampling technique in which the probability of getting any particular sample may be calculated. Nonprobability sampling does not meet this criterion and should be used with caution. Nonprobability sampling techniques cannot be used to infer from the sample to the general population. Any generalizations obtained from a nonprobability sample must be filtered through one s knowledge of the topic being studied. Performing nonprobability sampling is considerably less expensive than doing probability sampling, but the results are of limited value. Examples of nonprobability sampling include Convenience, Haphazard or Accidental sampling members of the population are chosen based on their relative ease of access. To sample friends, co workers, or shoppers at a single mall, are all examples of convenience sampling . Snowball sampling The first respondent refers a friend. The friend also refers a friend, etc. Judgmental sampling or Purposive sampling The researcher chooses the sample based on who they think would be appropriate for the study. This is used primarily when there is a limited number of people that have expertise in the area being researched. Deviant Case Get cases that substantially differ from the dominant pattern a special type of purposive sample . Case study The research is limited to one group, often with a similar characteristic or of small size. ad hoc quotas A quota ... studies due to unintentional or unavoidable characteristics of the sampling method. In public ... Marketing research Quantitative marketing research Sampling statistics Cluster sampling Multistage sampling Simple random sample Systematic sampling Stratified sampling DEFAULTSORT Nonprobability Sampling Category Sampling techniques Category Market research de Willk rliche Stichprobe pt Amostra ... more details
In the theory of finite population sampling statistics sampling , a sampling design specifies for every possible sample statistics sample its probability of being drawn. Mathematics Mathematically , a sampling design is denoted by the function math P S math which gives the probability of drawing a sample math S. math An example of a sampling design During Bernoulli sampling , math P S math is given by math P S q N text sample S times 1 q N text pop N text sample S math where for each element math q math is the probability of being included in the sample and math N text sample S math is the total number of elements in the sample math S math and math N text pop math is the total number of elements in the population before sampling commenced . See also Statistical sampling Bernoulli sampling Further reading Sarndal, Swenson, and Wretman 1992 , Model Assisted Survey Sampling, Springer Verlag, ISBN 0 387 40620 4 Category Sampling statistics statistics stub ... more details
Quota sampling is a method for selecting survey participants. In quota sampling, a population is first segmented into mutually exclusive sub groups, just as in stratified sampling . Then judgment is used to select the subjects or units from each segment based on a specified proportion. For example, an interviewer may be told to sample 200 females and 300 males between the age of 45 and 60. This means that individuals can put a demand on who they want to sample targeting This second step makes the technique non probability sampling. In quota sampling, the selection of the sample is non random unlike random sampling and can often be found unreliable. For example interviewers might be tempted to interview those people in the street who look most helpful, or may choose to use accidental sampling to question those closest to them, for time keeping sake. The problem is that these samples may be biased because not everyone gets a chance of selection. This non random element is its greatest weakness and quota versus probability has been a matter of controversy for many years. Quota sampling is useful when time is limited, a sampling frame is not available, the research budget is very tight or when detailed accuracy is not important. You can also choose how many of each category is selected. This is the non probability version of stratified sampling. Subsets are chosen and then either convenience or judgment sampling is used to choose people from each subset. Stratified sampling is probably the most commonly used probability method. Subsets of the population are created so that each subset has a common characteristic, such as gender. Random sampling chooses a number of subjects from each subset. More footnotes date July 2010 References Dodge, Y. 2003 The Oxford Dictionary of Statistical Terms , OUP. ISBN 0 19 920613 9 Category Sampling techniques de Quotenstichprobe ... more details
In the theory of finite population sampling , Poisson sampling is a sampling statistics sampling process where each element of the statistical population population that is sampled is subjected to an statistical independence independent Bernoulli trial which determines whether the element becomes part of the sample during the drawing of a single sample. Each element of the population may have a different probability of being included in the sample. The probability of being included in a sample during the drawing of a single sample is denoted as the first order inclusion probability of that element. If all first order inclusion probabilities are equal, Poisson sampling becomes equivalent to Bernoulli sampling , which can therefore be considered to be a special case of Poisson sampling. A mathematical consequence of Poisson sampling Mathematically, the first order inclusion probability of the i th element of the population is denoted by the symbol sub i sub and the second order inclusion probability that a pair consisting of the i th and j th element of the population that is sampled is included in a sample during the drawing of a single sample is denoted by sub ij sub . The following relation is valid during Poisson sampling math pi ij pi i times pi j . , math See also Bernoulli sampling Poisson distribution Poisson process Sampling design Further reading Sarndal, Swenson, and Wretman 1992 , Model Assisted Survey Sampling, Springer Verlag, ISBN 0 387 40620 4 Category Sampling statistics Category Sampling techniques ... more details
Acceptance sampling uses statistical sampling to determine whether to accept or reject a production lot of material. It has been a common quality control technique used in industry and particularly the military for contracts and procurement. A wide variety of acceptance sampling plan s are available. History Acceptance sampling procedures became common during WWII. Sampling plans, such as MIL STD 105 , were developed by Harold F. Dodge and others and became frequently used as Technical standard standards . More recently, quality assurance broadened the scope beyond final inspection to include all ... process control , HACCP , six sigma , and ISO 9000 . Some use of acceptance sampling still remains. Rationale Sampling provides one rational means of verifying verification that a production lot ... are part of the operating characteristic curve of the sampling plan. These are primarily statistical ... States defense standard that provided procedures and tables for sampling by attributes pass or fail ... ASQ Z1.4, Sampling Procedures and Tables for Inspection by Attributes . Several levels of inspection ... produces a number, other sampling plans such as those based on MIL STD 414 are often used. Compared with attriute sampling plans, these often use a smaller sample size for the same indexed AQL. See ... Number Sampling Plans, Fifth Edition, ASQ Press, ISBN 978 0 87389 739 6 ASQ standards Sampling Procedures and Tables for Inspection by Variables for Percent Nonconforming, ANSI ASQ Z1.9 2008 Sampling ... Practice for Probability Sampling Of Materials ASTM E122 Standard Practice for Calculating Sample ... ASTM E141 Standard Practice for Acceptance of Evdence Based on the Results of Probability Sampling ASTM E1402 Standard Terminology Relating to Sampling ASTM E1994 Standard Practice for Use of Process Oriented AOQL and LTPD Sampling Plans ASTM E2234 Standard Practice for Sampling a Stream of Product by Attributes Indexedby AQL Category Quality control tools Category Sampling statistics eu ... more details
Cluster sampling is a sampling statistics sampling technique used when natural groupings are evident in a statistical population . It is often used in marketing research. In this technique, the total population ... of these groups. A common motivation for cluster sampling is to reduce the average cost per interview ... exhaustive. A random sampling technique is then used on any relevant clusters to choose which clusters to include in the study. In single stage cluster sampling, all the elements from each of the selected clusters are used. In two stage cluster sampling, a random sampling technique is applied to the elements from each of the selected clusters. The main difference between cluster sampling and stratified sampling is that in cluster sampling the cluster is treated as the sampling unit so ... ampling, the analysis is done on elements within strata. In stratified sampling, a random sample is drawn from each of the strata, whereas in cluster sampling only the selected cluste rs are studied. The main objective of cluster sampling is to reduce costs by increasing sampling efficiency. This contrasts with stratified sampling where the main objective is to increase precision. There also exists multistage sampling, where more than two steps are taken in selecting clusters from clusters. Aspects of cluster sampling One version of cluster sampling is area sampling or geographical cluster sampling ... be expensive to survey, greater economy than simple random sampling can be achieved by treating several ... to size sampling is used. In this method, the probability of selecting any cluster varies with the size ... has the same probability of selection. Cluster sampling is used to estimate high mortalities in cases ... sampling error , which can be expressed in the so called design effect , the ratio between the number ... Journal , 316, 1455 1460. ref See also Sampling statistics Multistage sampling Simple random sampling References Reflist Category Sampling techniques Category Market research de Klumpen Stichprobe ... more details
Theoretical sampling refers to the process of choosing new research sites or cases to compare with ones that have already been studied. It is one of the tools of qualitative research . The term was coined by Barney Glaser and Anselm Strauss in 1967. The goal of theoretical sampling is not the same as with the sampling statistics probabilistic sampling the researcher s goal is not the representative capture of all possible variations, but to gain a deeper understanding of analysed cases and facilitate the development of analytic frame and concept s used in their research. Theoretical sampling can be viewed as a technique of data triangulation using independent pieces of information to get a better fix on something that is only partially known or understood. See also Grounded theory Sampling statistics Sampling case studies References Charles C. Ragin , Constructing Social Research The Unity and Diversity of Method , Pine Forge Press, 1994, ISBN 0 8039 9021 9 Barney G. Glaser & Anselm L. Strauss , The Discovery of Grounded Theory Strategies for Qualitative Research , Chicago, Aldine Publishing Company, 1967, ISBN 0 202 30260 1 Category Sociological terms ... more details
Description In statistics , sampling error or estimation error is the Errors and residuals in statistics error caused by observing a sample instead of the whole population. ref name Sarndal Sarndal, Swenson, and Wretman 1992 , Model Assisted Survey Sampling, Springer Verlag, ISBN 0 387 40620 4 ref The sampling error can be found by subtracting the value of a parameter from the value of a statistic. Citation needed date January 2010 In nursing research, a sampling error is the difference between a sample ... sample values of a statistic can theoretically be expressed as sampling errors, although in practice the exact sampling error is typically unknown. Sampling error also refers more broadly to this phenomenon of random sampling variation. An example of a sampling error in evolution is genetic ... that may or may not fairly represent the original population. What makes the bottleneck effect a sampling ... completely, making it a sampling error. Another example of genetic drift that is a sampling ..., making is a sampling error. ref Citation last1 Campbell first1 Neil A. last2 Reece first2 Jane B. title Biology publisher Benjamin Cummings pages 450 451 date year 2002 isbn ref The likely size of the sampling ... theory provides probability probabilistic estimates of the likely size of the sampling error ... statistics standard error . Sampling bias is a possible source of sampling errors. It leads to sampling ... to be systematic errors . Sampling error can be contrasted with non sampling error . Non sampling ... chosen, including various systematic error s and any random errors that are not due to sampling. Non sampling errors are much harder to quantify than sampling error. ref name Scheuren See also Margin of error Propagation of error Sampling statistics Citations Reflist Burns, N & Grove, S.K. 2009 . the Practice ... Survey Sampling, Springer Verlag, ISBN 0 387 40620 4 name Scheuren Fritz Scheuren 2005 . What is a Margin ... Sample Sizes Statistics stub Category Sampling statistics Category error Category Measurement ... more details
Vocal Sampling is an all male a cappella music group musical group from Cuba . They are distinctive for their rich a cappella adaptations of traditional Cuban salsa music , son music son , and Cuban rumba Rumba , such as their renditions of El Cuarto de Tula and La Negra Tomasa , vocally imitating the piano , Cowbell instrument cowbell , conga , Double bass bass , and trumpet , used originally in such songs. Their 2002 album Cambio de Tiempo lang en Change of Time was nominated for 3 Grammy Award s. ref Vocal Sampling at http www.timba.com artists vocalsampling index.asp timba.com retrieved 28 November 2006 ref Members Ren Ba os Jorge Chaviano Oscar Porro Abel Sanabria Reinaldo Sanler Renato Mora Discography Una Forma Mas April 1995 De Vacaciones July 1997 Live in Berlin January 2000 Cambio de Tiempo April 2002 Akapelleando January 2008 References reflist External links http vocalsampling.info Vocal Sampling official homepage Category Cuban musical groups Category A cappella musical groups Category Salsa music groups Category Professional a cappella groups band stub cuba stub de Vocal Sampling es Vocal Sampling fr Vocal Sampling ... more details
Work Sampling is the statistical technique for determining the proportion of time spent by workers in various defined categories of activity e.g. setting up a machine, assembling two parts, idle etc ref name Groover . It is as important as all other statistical techniques because it permits quick analysis, recognition, and enhancement of job responsibilities, tasks, performance competencies, and organizational work flows. Other names used for it are activity sampling , occurrence sampling , and ratio delay study ref name Sheth . In a work sampling study, a large number of Observation observations are made of the workers over an extended period of time. For statistical accuracy, the observations must be taken at random times during the period of study, and the period must be representative of the types of activities performed by the subjects. One important usage of the work sampling technique is the determination of the standard time for a manual manufacturing task. Similar techniques for calculating ... motion time system predetermined motion time systems . Characteristics of work sampling study The study of work sampling has some general characteristics related to the work condition. One of them is the sufficient time available to perform the study. A work sampling study usually requires a substantial ... the study. Another characteristic is multiple workers. Work sampling is commonly used to study ... number of categories. Steps in conducting a work sampling study There are several recommended steps when starting to prepare a work sampling study ref name Groover Define the manufacturing tasks ... needed. Identify the observers who will do the Sampling statistics sampling . Star the study .... Determining the Number of Observations Needed In Work Sampling After the work elements are defined ... percentage of working time math n math number of observations See also Sampling statistics Profiling computer programming can be done by work sampling a computer program. References Reflist refs ref ... more details
Refimprove date October 2009 Sampling is that part of statistical practice concerned with the selection ... making up the population may change over time. The three main advantages of sampling ... as independent objects or individuals. In survey sampling , survey weights can be applied to the data ... theory are employed to guide practice. In business and medical research, sampling is widely used ... publisher Wiley India isbn 9788126508099 year 2004 ref Process The sampling process comprises several stages Defining the population of concern Specifying a Sampling frame sampling frame , a Set mathematics set of items or events possible to measure Specifying a Sampling methods sampling method for selecting items or events from the frame Determining the sample size Implementing the sampling plan Sampling and data collecting Population definition Successful statistical practice is based on focused problem definition. In sampling, this includes defining the Statistical population population ... is an outcome. In such cases, sampling theory may treat the observed population as a sample from ... many issues, ambiguities and questions that would otherwise have been overlooked at this stage. Sampling frame main Sampling frame In the most straightforward case, such as the sentencing of a batch of material from production acceptance sampling by lots , it is possible to identify and measure every ... election in advance of the election . These imprecise populations are not amenable to sampling in any of the ways below and to which we could apply statistical theory. As a remedy, we seek a sampling ... poll , possible sampling frames include an electoral register and a telephone directory . Probability and nonprobability sampling A probability sampling scheme is one in which every unit in the population ... because all sampled units are given the same weight. Probability sampling includes Simple random sample Simple Random Sampling , Systematic sampling Systematic Sampling , Stratified Sampling , Probability ... more details
Cleanup date January 2009 Nofootnotes article date January 2009 In mathematical statistics , a sampling variogram is a graph that shows where a significant degree of causality in this context, spatial dependence in sample spaces or sampling units dissipates into randomness. A sampling variogram is obtained by plotting statisticallly significant variance terms of a temporally or in situ ordered set of measured values against the variance of the set and the lower limits of its asymmetric 95 and 99 confidence ranges. Corrected sampling variograms derive from uncorrected ones when extraneous measurement variances are subtracted before spatial dependence is verified. Bre X s bogus gold grades for crushed, salted and in situ ordered core samples of Borehole BSSE198 in Busang s South East zone give the following uncorrected sampling variogram. center Image Sampling variogram.jpg center http www.geostatscam.com corrected sampling variogram.htm The corrected sampling variogram for Bre X s bonanza borehole, its primary data set and test statistics are posted on this page. A temporally ordered set of on stream data for mill feed to a mineral processing plant, its test statistics and sampling variogram are given in http www.geostatscam.com Excel Appendix 20D.xls Appendix D of Sampling in Mineral Processing . A variogram or a semi variogram, unlike the above sampling variogram, does not show where spatial dependence in sample spaces dissipates into randomness because kriging variances of sets of kriged estimates are invalid measures for variability, precision and risk. References Armstrong, M and Champigny, N, 1988, A Study on Kriging Small Blocks, CIM Bulletin, Vol 82, No 923 Clark, I ... of sampling from bulk materials, Part 1 General Principles Journel, A G and Huijbregts, C J, 1978, Mining Geostatistics, Academic Press Inc, London 1978 Merks, J W, 1985, Sampling and Weighing of Bulk ... sampling variograms, and how to verify where spatial dependence in sample spaces or sampling units ... more details
otheruses2 Snowball In sociology and statistics research, snowball sampling is a technique for developing a research sampling statistics sample where existing study subjects recruit future subjects from ... builds up, enough data is gathered to be useful for research. This sampling technique is often ... be drug users or sex workers. As sample members are not selected from a sampling frame , snowball samples ... from snowball samples, but a variation of snowball sampling called respondent driven sampling has ... snowball samples under certain conditions. Snowball sampling and respondent driven sampling also allows ... Sampling? Snowball Sampling is a method used to obtain research and knowledge, from extended associations, through previous acquaintances, Snowball sampling uses recommendations to find people ... as snowball sampling because as more relationships are built through mutual association .... Snowball sampling is a useful tool for building networks and increasing the number of participants ... in the snowballing exercise . When to Use Snowball Sampling? There are many reasons why an individual may want to use snowball sampling across any industry, research, job, etc. Specific to business and marketing, however, snowball sampling can be used to things such as identify experts in a certain ... sampling. They called experts that they had contacts and after gathering information, asked them ... individuals in a specific field. Thus, snowball sampling can be used to gather expert information. Advantages There are many different kinds of sampling, each with their own advantages and disadvantages. Snowball sampling has a lot of advantages as opposed to other sampling methods. It is possible ... for your sampling group, and also can help you find lead users more simply. Disadvantages Snowball sampling is inexact, and can produce varied and inaccurate results. The method is heavily reliant on the skill of the individual conducting the actual sampling, and that individual s ability to vertically ... more details
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