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Misuse Of P-values
Misuse of ''p''-values is common in scientific research and scientific education. ''p''-values are often used or interpreted incorrectly; the American Statistical Association states that ''p''-values can indicate how incompatible the data are with a specified statistical model. From a Neyman–Pearson hypothesis testing approach to statistical inferences, the data obtained by comparing the ''p''-value to a significance level will yield one of two results: either the null hypothesis is rejected (which however does not prove that the null hypothesis is ''false''), or the null hypothesis ''cannot'' be rejected at that significance level (which however does not prove that the null hypothesis is ''true''). From a Fisherian statistical testing approach to statistical inferences, a low ''p''-value means ''either'' that the null hypothesis is true and a highly improbable event has occurred ''or'' that the null hypothesis is false. Clarifications about ''p''-values The following list cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific Research
The scientific method is an empirical method for acquiring knowledge that has characterized the development of science since at least the 17th century (with notable practitioners in previous centuries; see the article history of scientific method for additional detail.) It involves careful observation, applying rigorous skepticism about what is observed, given that cognitive assumptions can distort how one interprets the observation. It involves formulating hypotheses, via induction, based on such observations; the testability of hypotheses, experimental and the measurement-based statistical testing of deductions drawn from the hypotheses; and refinement (or elimination) of the hypotheses based on the experimental findings. These are ''principles'' of the scientific method, as distinguished from a definitive series of steps applicable to all scientific enterprises. Although procedures vary from one field of inquiry to another, the underlying process is frequently the sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Look-elsewhere Effect
The look-elsewhere effect is a phenomenon in the statistical analysis of scientific experiments where an apparently statistically significant observation may have actually arisen by chance because of the sheer size of the parameter space to be searched. Once the possibility of look-elsewhere error in an analysis is acknowledged, it can be compensated for by careful application of standard mathematical techniques. More generally known in statistics as the problem of multiple comparisons, the term gained some media attention in 2011, in the context of the search for the Higgs boson at the Large Hadron Collider. Use Many statistical tests deliver a p-value, the probability that a given result could be obtained by chance, assuming the hypothesis one seeks to prove is in fact false. When asking "does ''X'' affect ''Y''?", it is common to vary ''X'' and see if there is significant variation in ''Y'' as a result. If this p-value is less than some predetermined statistical significan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metascience
Metascience (also known as meta-research) is the use of scientific methodology to study science itself. Metascience seeks to increase the quality of scientific research while reducing inefficiency. It is also known as "''research on research''" and "''the science of science''", as it uses research methods to study how research is done and find where improvements can be made. Metascience concerns itself with all fields of research and has been described as "a bird's eye view of science". In the words of John Ioannidis, "Science is the best thing that has happened to human beings ... but we can do it better." In 1966, an early meta-research paper examined the statistical methods of 295 papers published in ten high-profile medical journals. It found that "in almost 73% of the reports read ... conclusions were drawn when the justification for these conclusions was invalid." Meta-research in the following decades found many methodological flaws, inefficiencies, and poor practices in r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Replication Crisis
The replication crisis (also called the replicability crisis and the reproducibility crisis) is an ongoing methodological crisis in which the results of many scientific studies are difficult or impossible to reproduce. Because the reproducibility of empirical results is an essential part of the scientific method, such failures undermine the credibility of theories building on them and potentially call into question substantial parts of scientific knowledge. The replication crisis is frequently discussed in relation to psychology and medicine, where considerable efforts have been undertaken to reinvestigate classic results, to determine both their reliability and, if found unreliable, the reasons for the failure. Data strongly indicate that other natural, and social sciences are affected as well. The phrase ''replication crisis'' was coined in the early 2010s as part of a growing awareness of the problem. Considerations of causes and remedies have given rise to a new scientific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estimation Statistics
Estimation statistics, or simply estimation, is a data analysis framework that uses a combination of effect sizes, confidence intervals, precision planning, and meta-analysis to plan experiments, analyze data and interpret results. It complements hypothesis testing approaches such as null hypothesis significance testing (NHST), by going beyond the question is an effect present or not, and provides information about how large an effect is. Estimation statistics is sometimes referred to as ''the new statistics''. The primary aim of estimation methods is to report an effect size (a point estimate) along with its confidence interval, the latter of which is related to the precision of the estimate. The confidence interval summarizes a range of likely values of the underlying population effect. Proponents of estimation see reporting a ''P'' value as an unhelpful distraction from the important business of reporting an effect size with its confidence intervals, and believe that estimat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family-wise Error Rate
In statistics, family-wise error rate (FWER) is the probability of making one or more false discoveries, or type I errors when performing multiple hypotheses tests. Familywise and Experimentwise Error Rates Tukey (1953) developed the concept of a familywise error rate as the probability of making a Type I error among a specified group, or "family," of tests. Based on Tukey (1953), Ryan (1959) proposed the related concept of an ''experimentwise error rate'', which is the probability of making a Type I error in a given experiment. Hence, an experimentwise error rate is a familywise error rate for all of the tests that are conducted within an experiment. As Ryan (1959, Footnote 3) explained, an experiment may contain two or more families of multiple comparisons, each of which relates to a particular statistical inference and each of which has its own separate familywise error rate. Hence, familywise error rates are usually based on theoretically informative collections of multiple c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expected Number
In probability theory, the expected value (also called expectation, expectancy, mathematical expectation, mean, average, or first moment) is a generalization of the weighted average. Informally, the expected value is the arithmetic mean of a large number of independently selected outcomes of a random variable. The expected value of a random variable with a finite number of outcomes is a weighted average of all possible outcomes. In the case of a continuum of possible outcomes, the expectation is defined by integration. In the axiomatic foundation for probability provided by measure theory, the expectation is given by Lebesgue integration. The expected value of a random variable is often denoted by , , or , with also often stylized as or \mathbb. History The idea of the expected value originated in the middle of the 17th century from the study of the so-called problem of points, which seeks to divide the stakes ''in a fair way'' between two players, who have to e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minitab
Minitab is a statistics package developed at the Pennsylvania State University by researchers Barbara F. Ryan, Thomas A. Ryan, Jr., and Brian L. Joiner in conjunction with Triola Statistics Company in 1972. It began as a light version of OMNITAB 80, a statistical analysis program by National Institute of Standards and Technology. History Minitab is a statistics package developed at the Pennsylvania State University by researchers Barbara F. Ryan, Thomas A. Ryan, Jr., Brian L. Joiner in 1972. The project received funding from the Triola Statistics Company. It began as a light version of OMNITAB 80, a statistical analysis program by NIST, which was conceived by Joseph Hilsenrath in years 1962-1964 as OMNITAB program for IBM 7090. The documentation for OMNITAB 80 was last published 1986, and there has been no significant development since then. Minitab is distributed by Minitab, LLC, a privately owned company headquartered in State College, Pennsylvania. In 2020, during the CO ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
No Starch Press
No Starch Press is an American publishing company, specializing in technical literature often geared towards the geek, hacker, and DIY subcultures. Popular titles include '' Hacking: The Art of Exploitation'', Andrew Huang's ''Hacking the Xbox'', and ''How Wikipedia Works''. Topics No Starch Press publishes books with a focus on networking, computer security, hacking, Linux, programming, technology for kids, Lego, math, and science. The publisher also releases educational comics like ''Super Scratch Programming Adventure'' and ''The Manga Guide to Science'' series. History San Francisco-based No Starch Press was founded in 1994 by Bill Pollock, who brings more than 30 years of publishing industry experience to the company. Several titles have been included in the prestigious ''Communication Arts'' Design Annual and STEP inside 100 competition, and have won the Independent Publisher Book Award (the IPPYs) from ''Independent Publisher'' magazine. Availability No Starch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acne
Acne, also known as ''acne vulgaris'', is a long-term Cutaneous condition, skin condition that occurs when Keratinocyte, dead skin cells and Sebum, oil from the skin clog hair follicles. Typical features of the condition include comedo, blackheads or whiteheads, pimples, oily skin, and possible scarring. It primarily affects skin with a relatively high number of sebaceous gland, oil glands, including the face, upper part of the chest, and back. The resulting appearance can lead to anxiety (mood), anxiety, reduced self-esteem, and, in extreme cases, clinical depression, depression or suicidal ideations, thoughts of suicide. Susceptibility to acne is primarily genetic in 80% of cases. The roles of diet and cigarette smoking in the condition are unclear, and neither hygiene, cleanliness nor exposure to sunlight appear to play a part. In both sexes, hormones called androgens appear to be part of the underlying mechanism, by causing increased production of sebum. Another common fac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jellybeans
Jelly beans are small bean shaped sugar candies with soft candy shells and thick gel interiors (see gelatin and jelly). The confection is primarily made of sugar and sold in a wide variety of colors and flavors. History It has been claimed that jelly beans were first mentioned during 1861, when Boston confectioner William Schrafft urged people to send his jelly beans to soldiers during the American Civil War. It was not until July 5, 1905, that jelly beans were mentioned in the ''Chicago Daily News''. The advertisement publicized bulk beans sold by volume for ten cents per pound, according to the book ''The Century in Food: America's Fads and Favorites''. Most historians contend that jelly beans were first associated with celebrations of Easter in the United States sometime during the 1930s due to their egg-like shape. Manufacture The basic ingredients of jelly beans include sugar, tapioca or corn syrup, and pectin or starch. Relatively minor amounts of the emulsifying ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xkcd
''xkcd'', sometimes styled ''XKCD'', is a webcomic created in 2005 by American author Randall Munroe. The comic's tagline describes it as "a webcomic of romance, sarcasm, math, and language". Munroe states on the comic's website that the name of the comic is not an initialism but "just a word with no phonetic pronunciation". The subject matter of the comic varies from statements on life and love to mathematical, programming, and scientific in-jokes. Some strips feature simple humor or pop-culture references. It has a cast of stick figures, and the comic occasionally features landscapes, graphs, charts, and intricate mathematical patterns such as fractals. New cartoons are added three times a week, on Mondays, Wednesdays, and Fridays. Munroe has released five spinoff books from the comic. The first book, published in 2010 and entitled ''xkcd: volume 0'', was a series of select comics from his website. His 2014 book '' What If?'' is based on his blog of the same name that ans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
