"[a scatter diagram] is a graph in which the values of two variables are plotted along two axes, the pattern of the resulting points revealing any correlation present. It graphs pairs of numerical data, with one variable on each axis, to look for a relationship between them. If the variables are correlated, the points will fall along a line or curve. The better the correlation, the tighter the points will have the line." (C S V Murthy, "Data and Businesss Analytics", 2020)
"Decision tree is a graphical representation of a decision situation in which decision situation points (nodes) are connected together by arcs (one for each alternative on a decision) and terminate in ovals (the action that is the result of all the decisions made on the path leading to that oval). [...] A tree is made up of multilevel group of elements called nodes. A node is nothing more than a point at which subsidiary data originate. This particular logical data structure is called a tree simply because it looks like a tree, usually turned upside down. Genealogists use a schema called a tree to show ancestral descent of a person, family or group. Data associated by a tree schema are hierarchical. They branch from a point or node without forming loops or polygons. Data presented in a tree structure make two conditions. First, the tree must have a single root node. Second, all nodes other than the root node must be related to one and only one higher level node." (C S V Murthy, "Data and Businesss Analytics", 2020)
"Every interaction includes both presentation and dialogue. Presentation provides the layout of information on a computer screen. Dialogue provides an interaction sequence between a user and computer. Interfaces and dialogue will help users to solve their problems. Presentation must include objects that the user can readily understand in terms of their daily work. The dialogue must correspond to user’s normal work and to their mental model of the system (Mental model is the way a user sees a problem). Both presentation/dialogue depend on what users are doing." (C S V Murthy, "Data and Businesss Analytics", 2020)
"Information relevance refers to the extent to which information is appropriate for the decision-making situation facing the manager. Extraneous or extra information distracts the decision-maker from the assigned task and information overload frustrates the decision-maker and impairs the decision-making process. Relevant information must pertain to the problems, decisions and responsibilities of the recipient." (C S V Murthy, "Data and Businesss Analytics", 2020)
"Information that is complete means information that covers key issues and is sufficient to support the decision-making situation at hand without critical omissions. The more complete a body of information, is obviously, the more expensive it is to develop and maintain. Care must also be taken not to provide extra information than needed, due to its expense, and not to provide so much information that the recipient will suffer from information overload (information indigestion)." (C S V Murthy, "Data and Businesss Analytics", 2020)
"Ridge Regression is a technique for analysing multiple regression data that suffer from multicollinearity. When multicollinearity occurs, least squares estimates are unbiased, but their variances are large. So, they may be far from the true value. By adding a degree of bias to the regression estimates, principal components regression reduces the standard errors." (C S V Murthy, "Data and Businesss Analytics", 2020)
"Spectral methods are a class of techniques used in applied mathematics and scientific computing to numerically solving certain differential equations, potentially involving the use of the fast Fourier transform. This is an algorithm that samples a signal over a period of time and divides it into its frequency components. These components are single sinusoidal oscillations at distant frequencies each with their own amplitude and phase." (C S V Murthy, "Data and Businesss Analytics", 2020)
"The concept of programmed decisions is important because the ultimate (and unachievable) goal of information systems is to provide purely programmed decisions. Because this is not possible, we seek to provide the optimum type of information to the human decision-maker, who then makes non-programmable decisions. Decisions lend themselves to programming techniques if they are repetitive and routine, and if a procedurs can be worked out for handling them so that each is neither an ad hoc decision nor one to be treated as a new situation each time it arises." (C S V Murthy, "Data and Businesss Analytics", 2020)
"Timeliness means that information is available when it is needed. Most managers function in a dynamic environment of change, demands updated and current information. Computerised information systems have the ability to gather, sort, analyse, store, retrieve, and transmit large amounts of information in a very short period of time. Completeness of information is the extent to which information is all there." (C S V Murthy, "Data and Businesss Analytics", 2020)
"Understanding complex information systems begins with a clear understanding of information and its general characteristics. Information can be considered as the very blood of an organisation, but it must be properly understood and appropriately distinguished from data. Too many times, the terms ‘data’ and ‘information’ are used interchangeably, but the terms most clearly mean entirely different things. Data should be defined as raw, unsummarised and unanalysed facts. Information is data that has been presented in such a way as to alter the receiver’s understanding. Data are the raw materials from which information is derived. This is a necessary distinction for the manager to make, because loads of data can be generated, without producing even one iota of useful information." (C S V Murthy, "Data and Businesss Analytics", 2020)
"Visualisation is any technique for creating images, diagrams or animations to communicate a message; techniques used to communicate data or information by encoding it as visual objects, e.g., points, lines or bars contained in graphics. One of the most important benefits of visualisation is that it allows us visual access to huge amounts of data in easily digestible visuals. Well designed data graphics are usually the simplest, and at the same time, the most powerful." (C S V Murthy, "Data and Businesss Analytics", 2020)
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