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Operations research

Operations research
Operations research, or operational research in British usage, is a discipline that deals with the application of advanced analytical methods to help make better decisions.[1] It is often considered to be a sub-field of mathematics.[2] The terms management science and decision science are sometimes used as synonyms.[3] Employing techniques from other mathematical sciences, such as mathematical modeling, statistical analysis, and mathematical optimization, operations research arrives at optimal or near-optimal solutions to complex decision-making problems. Because of its emphasis on human-technology interaction and because of its focus on practical applications, operations research has overlap with other disciplines, notably industrial engineering and operations management, and draws on psychology and organization science. Overview[edit] The major subdisciplines in modern operational research, as identified by the journal Operations Research,[6] are: History[edit] Historical origins[edit]

Related:  Research DesignLearn to code

Explanation This description may establish rules or laws, and may clarify the existing ones in relation to any objects, or phenomena examined. The components of an explanation can be implicit, and be interwoven with one another. In scientific research, explanation is one of several "purposes" for empirical research.[1] [2] Explanation is a way to uncover new knowledge, and to report relationships among different aspects of studied phenomena. Merging data in PowerPivot Update 9/23/13: Check an example using Power Query to deal with the same issue described on this article: One of the most common requests I have seen from data analysts working with PowerPivot is how to merge two or more datasets. For example, you are given the following two sales extracts and are asked then to generate a YTD report based on their composite data Extract 1 (Table 1): Extract 2 data (Table 2): If we want to report on total amount for the year, we must combine these two files.

Descriptive research Descriptive research is used to describe characteristics of a population or phenomenon being studied. It does not answer questions about how/when/why the characteristics occurred. Rather it addresses the "what" question (what are the characteristics of the population or situation being studied?) SQLBI - Marco Russo : Many-to-Many relationships in PowerPivot UPDATE: This blog post is still good for learning DAX principles, but a better description of many-to-many patterns is available on The Many-to-Many Revolution whitepaper that is available here: - please download it and use the pattern described there to write faster DAX formulas! PowerPivot doesn’t have the capability of really understand a many-to-many (M2M) relationship between two tables. In a relational world, a many-to-many relationship is materialized using a bridge table that split this relationship in two separate one-to-many relationships between the two original tables and the bridge table. Apparently, we can do the same in PowerPivot, but the behavior is not the expected one. Some workaround is possible using DAX, but there are some undesirable side effects if we only use calculated column.

Prediction A prediction (Latin præ-, "before," and dicere, "to say") or forecast is a statement about the way things will happen in the future, often but not always based on experience or knowledge. While there is much overlap between prediction and forecast, a prediction may be a statement that some outcome is expected, while a forecast is more specific, and may cover a range of possible outcomes.[clarification needed][citation needed] A "prediction" may be contrasted with a "projection", which is explicitly dependent on stated assumptions. Although guaranteed accurate information about the future is in many cases impossible, prediction can be useful to assist in making plans about possible developments; Howard H. Stevenson writes that prediction in business "... is at least two things: Important and hard.

PowerPivot Example PowerPivot Example: Building a Dashboard with PowerPivot Click below to download complete PowerPivot example in an Excel workbook. The example is explained in the text below.Download complete Excel example HERE. Every quarter your team spends countless hours preparing reports for the board meeting. Getting data from different reports, entering data into Excel, preparing exhibits and checking and rechecking formulas. After you get the first set of charts ready then you need even more – to explain this quarters variations.

Decision-making Sample flowchart representing the decision process to add a new article to Wikipedia. Decision-making can be regarded as the cognitive process resulting in the selection of a belief or a course of action among several alternative possibilities. Every decision-making process produces a final choice that may or may not prompt action. Decision-making is the study of identifying and choosing alternatives based on the values and preferences of the decision maker. Excel VBA Loops, with examples. For Loop; Do While Loop; Do Until Loop. User Rating: / 14Details Details Category: Excel VBA Excel VBA Loops, with examples. For Loop; Do While Loop; Do Until Loop. Exploratory research Exploratory research is research conducted for a problem that has not been clearly defined. It often occurs before we know enough to make conceptual distinctions or posit an explanatory relationship.[1] Exploratory research helps determine the best research design, data collection method and selection of subjects. It should draw definitive conclusions only with extreme caution.