Misplaced Pages

#393606

79-504: Data mining is a particular data analysis technique that focuses on statistical modeling and knowledge discovery for predictive rather than purely descriptive purposes, while business intelligence covers data analysis that relies heavily on aggregation, focusing mainly on business information. In statistical applications, data analysis can be divided into descriptive statistics , exploratory data analysis (EDA), and confirmatory data analysis (CDA). EDA focuses on discovering new features in

158-494: A ) and ( b ) minimize the error when the model predicts Y for a given range of values of X . Analysts may also attempt to build models that are descriptive of the data, in an aim to simplify analysis and communicate results. A data product is a computer application that takes data inputs and generates outputs , feeding them back into the environment. It may be based on a model or algorithm. For instance, an application that analyzes data about customer purchase history, and uses

237-650: A cluster of typical film lengths? - Is there a correlation between country of origin and MPG? - Do different genders have a preferred payment method? - Is there a trend of increasing film length over the years? Barriers to effective analysis may exist among the analysts performing the data analysis or among the audience. Distinguishing fact from opinion, cognitive biases, and innumeracy are all challenges to sound data analysis. You are entitled to your own opinion, but you are not entitled to your own facts. Daniel Patrick Moynihan Effective analysis requires obtaining relevant facts to answer questions, support

316-418: A comparison of CRISP-DM and SEMMA in 2008. Before data mining algorithms can be used, a target data set must be assembled. As data mining can only uncover patterns actually present in the data, the target data set must be large enough to contain these patterns while remaining concise enough to be mined within an acceptable time limit. A common source for data is a data mart or data warehouse . Pre-processing

395-611: A conclusion or formal opinion , or test hypotheses . Facts by definition are irrefutable, meaning that any person involved in the analysis should be able to agree upon them. For example, in August 2010, the Congressional Budget Office (CBO) estimated that extending the Bush tax cuts of 2001 and 2003 for the 2011–2020 time period would add approximately $ 3.3 trillion to the national debt. Everyone should be able to agree that indeed this

474-507: A data set and transforming the information into a comprehensible structure for further use. Data mining is the analysis step of the " knowledge discovery in databases " process, or KDD. Aside from the raw analysis step, it also involves database and data management aspects, data pre-processing , model and inference considerations, interestingness metrics, complexity considerations, post-processing of discovered structures, visualization , and online updating . The term "data mining"

553-524: A higher likelihood of being input incorrectly. Textual data spell checkers can be used to lessen the amount of mistyped words. However, it is harder to tell if the words themselves are correct. Once the datasets are cleaned, they can then be analyzed. Analysts may apply a variety of techniques, referred to as exploratory data analysis , to begin understanding the messages contained within the obtained data. The process of data exploration may result in additional data cleaning or additional requests for data; thus,

632-400: A kind of summary of the input data, and may be used in further analysis or, for example, in machine learning and predictive analytics . For example, the data mining step might identify multiple groups in the data, which can then be used to obtain more accurate prediction results by a decision support system . Neither the data collection, data preparation, nor result interpretation and reporting

711-427: A large volume of data. The related terms data dredging , data fishing , and data snooping refer to the use of data mining methods to sample parts of a larger population data set that are (or may be) too small for reliable statistical inferences to be made about the validity of any patterns discovered. These methods can, however, be used in creating new hypotheses to test against the larger data populations. In

790-477: A new sample of data, therefore bearing little use. This is sometimes caused by investigating too many hypotheses and not performing proper statistical hypothesis testing . A simple version of this problem in machine learning is known as overfitting , but the same problem can arise at different phases of the process and thus a train/test split—when applicable at all—may not be sufficient to prevent this from happening. The final step of knowledge discovery from data

869-558: A number is rising or falling may not be the key factor. More important may be the number relative to another number, such as the size of government revenue or spending relative to the size of the economy (GDP) or the amount of cost relative to revenue in corporate financial statements. This numerical technique is referred to as normalization or common-sizing. There are many such techniques employed by analysts, whether adjusting for inflation (i.e., comparing real vs. nominal data) or considering population increases, demographics, etc. Analysts apply

SECTION 10

#1732869451394

948-550: A text label for numbers). Data is collected from a variety of sources. A list of data sources are available for study & research. The requirements may be communicated by analysts to custodians of the data; such as, Information Technology personnel within an organization. Data collection or data gathering is the process of gathering and measuring information on targeted variables in an established system, which then enables one to answer relevant questions and evaluate outcomes. The data may also be collected from sensors in

1027-604: A variety of aliases, ranging from "experimentation" (positive) to "fishing" or "snooping" (negative). The term data mining appeared around 1990 in the database community, with generally positive connotations. For a short time in 1980s, the phrase "database mining"™, was used, but since it was trademarked by HNC, a San Diego –based company, to pitch their Database Mining Workstation; researchers consequently turned to data mining . Other terms used include data archaeology , information harvesting , information discovery , knowledge extraction , etc. Gregory Piatetsky-Shapiro coined

1106-550: A variety of analytical techniques. For example; with financial information, the totals for particular variables may be compared against separately published numbers that are believed to be reliable. Unusual amounts, above or below predetermined thresholds, may also be reviewed. There are several types of data cleaning, that are dependent upon the type of data in the set; this could be phone numbers, email addresses, employers, or other values. Quantitative data methods for outlier detection, can be used to get rid of data that appears to have

1185-478: A variety of techniques to address the various quantitative messages described in the section above. Data mining Data mining is the process of extracting and discovering patterns in large data sets involving methods at the intersection of machine learning , statistics , and database systems . Data mining is an interdisciplinary subfield of computer science and statistics with an overall goal of extracting information (with intelligent methods) from

1264-498: Is a misnomer because the goal is the extraction of patterns and knowledge from large amounts of data, not the extraction ( mining ) of data itself . It also is a buzzword and is frequently applied to any form of large-scale data or information processing ( collection , extraction , warehousing , analysis, and statistics) as well as any application of computer decision support system , including artificial intelligence (e.g., machine learning) and business intelligence . Often

1343-513: Is a certain unemployment rate (X) necessary for a certain inflation rate (Y)?"). Whereas (multiple) regression analysis uses additive logic where each X-variable can produce the outcome and the X's can compensate for each other (they are sufficient but not necessary), necessary condition analysis (NCA) uses necessity logic, where one or more X-variables allow the outcome to exist, but may not produce it (they are necessary but not sufficient). Each single necessary condition must be present and compensation

1422-574: Is a precursor to data analysis, and data analysis is closely linked to data visualization and data dissemination. Analysis refers to dividing a whole into its separate components for individual examination. Data analysis is a process for obtaining raw data , and subsequently converting it into information useful for decision-making by users. Data is collected and analyzed to answer questions, test hypotheses, or disprove theories. Statistician John Tukey , defined data analysis in 1961, as: "Procedures for analyzing data, techniques for interpreting

1501-400: Is an approach of analyzing data sets to summarize their main characteristics, often using statistical graphics and other data visualization methods. A statistical model can be used or not, but primarily EDA is for seeing what the data can tell beyond the formal modeling and thereby contrasts with traditional hypothesis testing, in which a model is supposed to be selected before the data

1580-420: Is essential to analyze the multivariate data sets before data mining. The target set is then cleaned. Data cleaning removes the observations containing noise and those with missing data . Data mining involves six common classes of tasks: Data mining can unintentionally be misused, producing results that appear to be significant but which do not actually predict future behavior and cannot be reproduced on

1659-475: Is necessary as inputs to the analysis, which is specified based upon the requirements of those directing the analytics (or customers, who will use the finished product of the analysis). The general type of entity upon which the data will be collected is referred to as an experimental unit (e.g., a person or population of people). Specific variables regarding a population (e.g., age and income) may be specified and obtained. Data may be numerical or categorical (i.e.,

SECTION 20

#1732869451394

1738-410: Is not data mining per se , but a result of the preparation of data before—and for the purposes of—the analysis. The threat to an individual's privacy comes into play when the data, once compiled, cause the data miner, or anyone who has access to the newly compiled data set, to be able to identify specific individuals, especially when the data were originally anonymous. It is recommended to be aware of

1817-513: Is not possible. Users may have particular data points of interest within a data set, as opposed to the general messaging outlined above. Such low-level user analytic activities are presented in the following table. The taxonomy can also be organized by three poles of activities: retrieving values, finding data points, and arranging data points. - How long is the movie Gone with the Wind? - What comedies have won awards? - Which funds underperformed

1896-447: Is part of the data mining step, although they do belong to the overall KDD process as additional steps. The difference between data analysis and data mining is that data analysis is used to test models and hypotheses on the dataset, e.g., analyzing the effectiveness of a marketing campaign , regardless of the amount of data. In contrast, data mining uses machine learning and statistical models to uncover clandestine or hidden patterns in

1975-577: Is seen. Exploratory data analysis has been promoted by John Tukey since 1970 to encourage statisticians to explore the data, and possibly formulate hypotheses that could lead to new data collection and experiments. EDA is different from initial data analysis (IDA) , which focuses more narrowly on checking assumptions required for model fitting and hypothesis testing, and handling missing values and making transformations of variables as needed. EDA encompasses IDA. Tukey defined data analysis in 1961 as: "Procedures for analyzing data, techniques for interpreting

2054-410: Is to verify that the patterns produced by the data mining algorithms occur in the wider data set. Not all patterns found by the algorithms are necessarily valid. It is common for data mining algorithms to find patterns in the training set which are not present in the general data set. This is called overfitting . To overcome this, the evaluation uses a test set of data on which the data mining algorithm

2133-469: Is true or false. For example, the hypothesis might be that "Unemployment has no effect on inflation", which relates to an economics concept called the Phillips Curve . Hypothesis testing involves considering the likelihood of Type I and type II errors , which relate to whether the data supports accepting or rejecting the hypothesis. Regression analysis may be used when the analyst is trying to determine

2212-488: Is what CBO reported; they can all examine the report. This makes it a fact. Whether persons agree or disagree with the CBO is their own opinion. As another example, the auditor of a public company must arrive at a formal opinion on whether financial statements of publicly traded corporations are "fairly stated, in all material respects". This requires extensive analysis of factual data and evidence to support their opinion. When making

2291-678: The Cross-industry standard process for data mining (CRISP-DM) which defines six phases: or a simplified process such as (1) Pre-processing, (2) Data Mining, and (3) Results Validation. Polls conducted in 2002, 2004, 2007 and 2014 show that the CRISP-DM methodology is the leading methodology used by data miners. The only other data mining standard named in these polls was SEMMA . However, 3–4 times as many people reported using CRISP-DM. Several teams of researchers have published reviews of data mining process models, and Azevedo and Santos conducted

2370-882: The Database Directive . On the recommendation of the Hargreaves review , this led to the UK government to amend its copyright law in 2014 to allow content mining as a limitation and exception . The UK was the second country in the world to do so after Japan, which introduced an exception in 2009 for data mining. However, due to the restriction of the Information Society Directive (2001), the UK exception only allows content mining for non-commercial purposes. UK copyright law also does not allow this provision to be overridden by contractual terms and conditions. Since 2020 also Switzerland has been regulating data mining by allowing it in

2449-478: The Laplacian tradition's emphasis on exponential families . John W. Tukey wrote the book Exploratory Data Analysis in 1977. Tukey held that too much emphasis in statistics was placed on statistical hypothesis testing (confirmatory data analysis); more emphasis needed to be placed on using data to suggest hypotheses to test. In particular, he held that confusing the two types of analyses and employing them on

Data analysis - Misplaced Pages Continue

2528-487: The MECE principle . Each layer can be broken down into its components; each of the sub-components must be mutually exclusive of each other and collectively add up to the layer above them. The relationship is referred to as "Mutually Exclusive and Collectively Exhaustive" or MECE. For example, profit by definition can be broken down into total revenue and total cost. In turn, total revenue can be analyzed by its components, such as

2607-650: The Total Information Awareness Program or in ADVISE , has raised privacy concerns. Data mining requires data preparation which uncovers information or patterns which compromise confidentiality and privacy obligations. A common way for this to occur is through data aggregation . Data aggregation involves combining data together (possibly from various sources) in a way that facilitates analysis (but that also might make identification of private, individual-level data deducible or otherwise apparent). This

2686-607: The US Congress via the passage of regulatory controls such as the Health Insurance Portability and Accountability Act (HIPAA). The HIPAA requires individuals to give their "informed consent" regarding information they provide and its intended present and future uses. According to an article in Biotech Business Week , "'[i]n practice, HIPAA may not offer any greater protection than the longstanding regulations in

2765-559: The empirical distribution are defined for all distributions, unlike the mean and standard deviation ; moreover, the quartiles and median are more robust to skewed or heavy-tailed distributions than traditional summaries (the mean and standard deviation). The packages S , S-PLUS , and R included routines using resampling statistics , such as Quenouille and Tukey's jackknife and Efron 's bootstrap , which are nonparametric and robust (for many problems). Exploratory data analysis, robust statistics, nonparametric statistics, and

2844-413: The median test . Findings from EDA are orthogonal to the primary analysis task. To illustrate, consider an example from Cook et al. where the analysis task is to find the variables which best predict the tip that a dining party will give to the waiter. The variables available in the data collected for this task are: the tip amount, total bill, payer gender, smoking/non-smoking section, time of day, day of

2923-455: The 1960s, statisticians and economists used terms like data fishing or data dredging to refer to what they considered the bad practice of analyzing data without an a-priori hypothesis. The term "data mining" was used in a similarly critical way by economist Michael Lovell in an article published in the Review of Economic Studies in 1983. Lovell indicates that the practice "masquerades under

3002-695: The DMG. Data mining is used wherever there is digital data available. Notable examples of data mining can be found throughout business, medicine, science, finance, construction, and surveillance. While the term "data mining" itself may have no ethical implications, it is often associated with the mining of information in relation to user behavior (ethical and otherwise). The ways in which data mining can be used can in some cases and contexts raise questions regarding privacy , legality, and ethics . In particular, data mining government or commercial data sets for national security or law enforcement purposes, such as in

3081-505: The ICDE Conference, SIGMOD Conference and International Conference on Very Large Data Bases . There have been some efforts to define standards for the data mining process, for example, the 1999 European Cross Industry Standard Process for Data Mining (CRISP-DM 1.0) and the 2004 Java Data Mining standard (JDM 1.0). Development on successors to these processes (CRISP-DM 2.0 and JDM 2.0) was active in 2006 but has stalled since. JDM 2.0

3160-504: The SP-500? - What is the gross income of all stores combined? - How many manufacturers of cars are there? - What director/film has won the most awards? - What Marvel Studios film has the most recent release date? - Rank the cereals by calories. - What is the range of car horsepowers? - What actresses are in the data set? - What is the age distribution of shoppers? - Are there any outliers in protein? - Is there

3239-532: The United States have failed. In the United Kingdom in particular there have been cases of corporations using data mining as a way to target certain groups of customers forcing them to pay unfairly high prices. These groups tend to be people of lower socio-economic status who are not savvy to the ways they can be exploited in digital market places. In the United States, privacy concerns have been addressed by

Data analysis - Misplaced Pages Continue

3318-535: The attitude taken than by particular techniques. Typical graphical techniques used in EDA are: Dimensionality reduction : Typical quantitative techniques are: Many EDA ideas can be traced back to earlier authors, for example: The Open University course Statistics in Society (MDST 242), took the above ideas and merged them with Gottfried Noether 's work, which introduced statistical inference via coin-tossing and

3397-421: The data in order to identify relationships among the variables; for example, using correlation or causation . In general terms, models may be developed to evaluate a specific variable based on other variable(s) contained within the dataset, with some residual error depending on the implemented model's accuracy ( e.g. , Data = Model + Error). Inferential statistics includes utilizing techniques that measure

3476-490: The data visualization of data after conducting the analysis. Tukey's championing of EDA encouraged the development of statistical computing packages, especially S at Bell Labs . The S programming language inspired the systems S-PLUS and R . This family of statistical-computing environments featured vastly improved dynamic visualization capabilities, which allowed statisticians to identify outliers , trends and patterns in data that merited further study. Tukey's EDA

3555-438: The data while CDA focuses on confirming or falsifying existing hypotheses . Predictive analytics focuses on the application of statistical models for predictive forecasting or classification, while text analytics applies statistical, linguistic, and structural techniques to extract and classify information from textual sources, a species of unstructured data . All of the above are varieties of data analysis. Data integration

3634-471: The data. Stephen Few described eight types of quantitative messages that users may attempt to understand or communicate from a set of data and the associated graphs used to help communicate the message. Customers specifying requirements and analysts performing the data analysis may consider these messages during the course of the process. Author Jonathan Koomey has recommended a series of best practices for understanding quantitative data. These include: For

3713-483: The degree and source of the uncertainty involved in the conclusions. He emphasized procedures to help surface and debate alternative points of view. Effective analysts are generally adept with a variety of numerical techniques. However, audiences may not have such literacy with numbers or numeracy ; they are said to be innumerate. Persons communicating the data may also be attempting to mislead or misinform, deliberately using bad numerical techniques. For example, whether

3792-415: The development of statistical programming languages facilitated statisticians' work on scientific and engineering problems. Such problems included the fabrication of semiconductors and the understanding of communications networks, which concerned Bell Labs. These statistical developments, all championed by Tukey, were designed to complement the analytic theory of testing statistical hypotheses , particularly

3871-410: The environment, including traffic cameras, satellites, recording devices, etc. It may also be obtained through interviews, downloads from online sources, or reading documentation. Data, when initially obtained, must be processed or organized for analysis. For instance, these may involve placing data into rows and columns in a table format ( known as structured data ) for further analysis, often through

3950-449: The extent to which independent variable X affects dependent variable Y (e.g., "To what extent do changes in the unemployment rate (X) affect the inflation rate (Y)?"). This is an attempt to model or fit an equation line or curve to the data, such that Y is a function of X. Necessary condition analysis (NCA) may be used when the analyst is trying to determine the extent to which independent variable X allows variable Y (e.g., "To what extent

4029-413: The field of machine learning, such as neural networks , cluster analysis , genetic algorithms (1950s), decision trees and decision rules (1960s), and support vector machines (1990s). Data mining is the process of applying these methods with the intention of uncovering hidden patterns. in large data sets. It bridges the gap from applied statistics and artificial intelligence (which usually provide

SECTION 50

#1732869451394

4108-499: The following before data are collected: Data may also be modified so as to become anonymous, so that individuals may not readily be identified. However, even " anonymized " data sets can potentially contain enough information to allow identification of individuals, as occurred when journalists were able to find several individuals based on a set of search histories that were inadvertently released by AOL. The inadvertent revelation of personally identifiable information leading to

4187-488: The initialization of the iterative phases mentioned in the lead paragraph of this section. Descriptive statistics , such as, the average or median, can be generated to aid in understanding the data. Data visualization is also a technique used, in which the analyst is able to examine the data in a graphical format in order to obtain additional insights, regarding the messages within the data. Mathematical formulas or models (also known as algorithms ), may be applied to

4266-676: The leap from facts to opinions, there is always the possibility that the opinion is erroneous . There are a variety of cognitive biases that can adversely affect analysis. For example, confirmation bias is the tendency to search for or interpret information in a way that confirms one's preconceptions. In addition, individuals may discredit information that does not support their views. Analysts may be trained specifically to be aware of these biases and how to overcome them. In his book Psychology of Intelligence Analysis , retired CIA analyst Richards Heuer wrote that analysts should clearly delineate their assumptions and chains of inference and specify

4345-627: The learned patterns and turn them into knowledge. The premier professional body in the field is the Association for Computing Machinery 's (ACM) Special Interest Group (SIG) on Knowledge Discovery and Data Mining ( SIGKDD ). Since 1989, this ACM SIG has hosted an annual international conference and published its proceedings, and since 1999 it has published a biannual academic journal titled "SIGKDD Explorations". Computer science conferences on data mining include: Data mining topics are also present in many data management/database conferences such as

4424-494: The majority of businesses in the U.S. is not controlled by any legislation. Under European copyright database laws , the mining of in-copyright works (such as by web mining ) without the permission of the copyright owner is not legal. Where a database is pure data in Europe, it may be that there is no copyright—but database rights may exist, so data mining becomes subject to intellectual property owners' rights that are protected by

4503-407: The mathematical background) to database management by exploiting the way data is stored and indexed in databases to execute the actual learning and discovery algorithms more efficiently, allowing such methods to be applied to ever-larger data sets. The knowledge discovery in databases (KDD) process is commonly defined with the stages: It exists, however, in many variations on this theme, such as

4582-405: The message more clearly and efficiently to the audience. Data visualization uses information displays (graphics such as, tables and charts) to help communicate key messages contained in the data. Tables are a valuable tool by enabling the ability of a user to query and focus on specific numbers; while charts (e.g., bar charts or line charts), may help explain the quantitative messages contained in

4661-618: The more general terms ( large scale ) data analysis and analytics —or, when referring to actual methods, artificial intelligence and machine learning —are more appropriate. The actual data mining task is the semi- automatic or automatic analysis of large quantities of data to extract previously unknown, interesting patterns such as groups of data records ( cluster analysis ), unusual records ( anomaly detection ), and dependencies ( association rule mining , sequential pattern mining ). This usually involves using database techniques such as spatial indices . These patterns can then be seen as

4740-405: The patterns can then be measured from how many e-mails they correctly classify. Several statistical methods may be used to evaluate the algorithm, such as ROC curves . If the learned patterns do not meet the desired standards, it is necessary to re-evaluate and change the pre-processing and data mining steps. If the learned patterns do meet the desired standards, then the final step is to interpret

4819-620: The presiding judge on the case ruled that Google's digitization project of in-copyright books was lawful, in part because of the transformative uses that the digitization project displayed—one being text and data mining. The following applications are available under free/open-source licenses. Public access to application source code is also available. The following applications are available under proprietary licenses. For more information about extracting information out of data (as opposed to analyzing data), see: Exploratory data analysis In statistics , exploratory data analysis (EDA)

SECTION 60

#1732869451394

4898-467: The provider violates Fair Information Practices. This indiscretion can cause financial, emotional, or bodily harm to the indicated individual. In one instance of privacy violation , the patrons of Walgreens filed a lawsuit against the company in 2011 for selling prescription information to data mining companies who in turn provided the data to pharmaceutical companies. Europe has rather strong privacy laws, and efforts are underway to further strengthen

4977-402: The relationships between particular variables. For example, regression analysis may be used to model whether a change in advertising ( independent variable X ), provides an explanation for the variation in sales ( dependent variable Y ). In mathematical terms, Y (sales) is a function of X (advertising). It may be described as ( Y = aX + b + error), where the model is designed such that (

5056-587: The research arena,' says the AAHC. More importantly, the rule's goal of protection through informed consent is approach a level of incomprehensibility to average individuals." This underscores the necessity for data anonymity in data aggregation and mining practices. U.S. information privacy legislation such as HIPAA and the Family Educational Rights and Privacy Act (FERPA) applies only to the specific areas that each such law addresses. The use of data mining by

5135-574: The research field under certain conditions laid down by art. 24d of the Swiss Copyright Act. This new article entered into force on 1 April 2020. The European Commission facilitated stakeholder discussion on text and data mining in 2013, under the title of Licences for Europe. The focus on the solution to this legal issue, such as licensing rather than limitations and exceptions, led to representatives of universities, researchers, libraries, civil society groups and open access publishers to leave

5214-409: The results of such procedures, ways of planning the gathering of data to make its analysis easier, more precise or more accurate, and all the machinery and results of (mathematical) statistics which apply to analyzing data." Exploratory data analysis is an analysis technique to analyze and investigate the data set and summarize the main characteristics of the dataset. Main advantage of EDA is providing

5293-483: The results of such procedures, ways of planning the gathering of data to make its analysis easier, more precise or more accurate, and all the machinery and results of (mathematical) statistics which apply to analyzing data." There are several phases that can be distinguished, described below. The phases are iterative , in that feedback from later phases may result in additional work in earlier phases. The CRISP framework , used in data mining , has similar steps. The data

5372-457: The results to recommend other purchases the customer might enjoy. Once data is analyzed, it may be reported in many formats to the users of the analysis to support their requirements. The users may have feedback, which results in additional analysis. As such, much of the analytical cycle is iterative. When determining how to communicate the results, the analyst may consider implementing a variety of data visualization techniques to help communicate

5451-410: The revenue of divisions A, B, and C (which are mutually exclusive of each other) and should add to the total revenue (collectively exhaustive). Analysts may use robust statistical measurements to solve certain analytical problems. Hypothesis testing is used when a particular hypothesis about the true state of affairs is made by the analyst and data is gathered to determine whether that state of affairs

5530-521: The rights of the consumers. However, the U.S.–E.U. Safe Harbor Principles , developed between 1998 and 2000, currently effectively expose European users to privacy exploitation by U.S. companies. As a consequence of Edward Snowden 's global surveillance disclosure , there has been increased discussion to revoke this agreement, as in particular the data will be fully exposed to the National Security Agency , and attempts to reach an agreement with

5609-404: The same set of data can lead to systematic bias owing to the issues inherent in testing hypotheses suggested by the data . The objectives of EDA are to: Many EDA techniques have been adopted into data mining . They are also being taught to young students as a way to introduce them to statistical thinking. There are a number of tools that are useful for EDA, but EDA is characterized more by

5688-559: The stakeholder dialogue in May 2013. US copyright law , and in particular its provision for fair use , upholds the legality of content mining in America, and other fair use countries such as Israel, Taiwan and South Korea. As content mining is transformative, that is it does not supplant the original work, it is viewed as being lawful under fair use. For example, as part of the Google Book settlement

5767-960: The term "knowledge discovery in databases" for the first workshop on the same topic (KDD-1989) and this term became more popular in the AI and machine learning communities. However, the term data mining became more popular in the business and press communities. Currently, the terms data mining and knowledge discovery are used interchangeably. The manual extraction of patterns from data has occurred for centuries. Early methods of identifying patterns in data include Bayes' theorem (1700s) and regression analysis (1800s). The proliferation, ubiquity and increasing power of computer technology have dramatically increased data collection, storage, and manipulation ability. As data sets have grown in size and complexity, direct "hands-on" data analysis has increasingly been augmented with indirect, automated data processing, aided by other discoveries in computer science, specially in

5846-523: The use of spreadsheet(excel) or statistical software. Once processed and organized, the data may be incomplete, contain duplicates, or contain errors. The need for data cleaning will arise from problems in the way that the datum are entered and stored. Data cleaning is the process of preventing and correcting these errors. Common tasks include record matching, identifying inaccuracy of data, overall quality of existing data, deduplication, and column segmentation. Such data problems can also be identified through

5925-413: The variables under examination, analysts typically obtain descriptive statistics for them, such as the mean (average), median , and standard deviation . They may also analyze the distribution of the key variables to see how the individual values cluster around the mean. The consultants at McKinsey and Company named a technique for breaking a quantitative problem down into its component parts called

6004-416: The week, and size of the party. The primary analysis task is approached by fitting a regression model where the tip rate is the response variable. The fitted model is which says that as the size of the dining party increases by one person (leading to a higher bill), the tip rate will decrease by 1%, on average. However, exploring the data reveals other interesting features not described by this model. What

6083-406: Was not trained. The learned patterns are applied to this test set, and the resulting output is compared to the desired output. For example, a data mining algorithm trying to distinguish "spam" from "legitimate" e-mails would be trained on a training set of sample e-mails. Once trained, the learned patterns would be applied to the test set of e-mails on which it had not been trained. The accuracy of

6162-434: Was related to two other developments in statistical theory : robust statistics and nonparametric statistics , both of which tried to reduce the sensitivity of statistical inferences to errors in formulating statistical models . Tukey promoted the use of five number summary of numerical data—the two extremes ( maximum and minimum ), the median , and the quartiles —because these median and quartiles, being functions of

6241-705: Was withdrawn without reaching a final draft. For exchanging the extracted models—in particular for use in predictive analytics —the key standard is the Predictive Model Markup Language (PMML), which is an XML -based language developed by the Data Mining Group (DMG) and supported as exchange format by many data mining applications. As the name suggests, it only covers prediction models, a particular data mining task of high importance to business applications. However, extensions to cover (for example) subspace clustering have been proposed independently of

#393606