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Forecast Error
In statistics, a forecast error is the difference between the actual or real and the predicted or forecast value of a time series or any other phenomenon of interest. Since the forecast error is derived from the same scale of data, comparisons between the forecast errors of different series can only be made when the series are on the same scale. In simple cases, a forecast is compared with an outcome at a single time-point and a summary of forecast errors is constructed over a collection of such time-points. Here the forecast may be assessed using the difference or using a proportional error. By convention, the error is defined using the value of the outcome ''minus'' the value of the forecast. In other cases, a forecast may consist of predicted values over a number of lead-times; in this case an assessment of forecast error may need to consider more general ways of assessing the match between the time-profiles of the forecast and the outcome. If a main application of the forecas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Statistics
Statistics (from German language, German: ''wikt:Statistik#German, Statistik'', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a scientific, industrial, or social problem, it is conventional to begin with a statistical population or a statistical model to be studied. Populations can be diverse groups of people or objects such as "all people living in a country" or "every atom composing a crystal". Statistics deals with every aspect of data, including the planning of data collection in terms of the design of statistical survey, surveys and experimental design, experiments.Dodge, Y. (2006) ''The Oxford Dictionary of Statistical Terms'', Oxford University Press. When census data cannot be collected, statisticians collect data by developing specific experiment designs and survey sample (statistics), samples. Representative sampling as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Recession
The Great Recession was a period of marked general decline, i.e. a recession, observed in national economies globally that occurred from late 2007 into 2009. The scale and timing of the recession varied from country to country (see map). At the time, the International Monetary Fund (IMF) concluded that it was the most severe economic and financial meltdown since the Great Depression. One result was a serious disruption of normal international relations. The causes of the Great Recession include a combination of vulnerabilities that developed in the financial system, along with a series of triggering events that began with the bursting of the United States housing bubble in 2005–2012. When housing prices fell and homeowners began to abandon their mortgages, the value of mortgage-backed securities held by investment banks declined in 2007–2008, causing several to collapse or be bailed out in September 2008. This 2007–2008 phase was called the subprime mortgage crisis. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optimism Bias
Optimism bias (or the optimistic bias) is a cognitive bias that causes someone to believe that they themselves are less likely to experience a negative event. It is also known as unrealistic optimism or comparative optimism. Optimism bias is common and transcends gender, ethnicity, nationality, and age.O’Sullivan, Owen P. (2015)The neural basis of always looking on the bright side.''Dialogues in Philosophy, Mental and Neuro Sciences'', 8(1):11–15. Optimistic biases are even reported in non-human animals such as rats and birds. However, autistic people are less susceptible to optimistic biases. Four factors can cause a person to be optimistically biased: their desired end state, their cognitive mechanisms, the information they have about themselves versus others, and overall mood. The optimistic bias is seen in a number of situations. For example: people believing that they are less at risk of being a crime victim, smokers believing that they are less likely to contract lung can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mean Squared Prediction Error
In statistics the mean squared prediction error or mean squared error of the predictions of a smoothing or curve fitting procedure is the expected value of the squared difference between the fitted values implied by the predictive function \widehat and the values of the (unobservable) function ''g''. It is an inverse measure of the explanatory power of \widehat, and can be used in the process of cross-validation of an estimated model. If the smoothing or fitting procedure has projection matrix (i.e., hat matrix) ''L'', which maps the observed values vector y to predicted values vector \hat via \hat=Ly, then :\operatorname(L)=\operatorname\left left( g(x_i)-\widehat(x_i)\right)^2\right The MSPE can be decomposed into two terms: the mean of squared biases of the fitted values and the mean of variances of the fitted values: :n\cdot\operatorname(L)=\sum_^n\left(\operatorname\left widehat(x_i)\rightg(x_i)\right)^2+\sum_^n\operatorname\left widehat(x_i)\right Knowledge of ''g'' is r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forecasting Accuracy
Forecasting is the process of making predictions based on past and present data. Later these can be compared (resolved) against what happens. For example, a company might estimate their revenue in the next year, then compare it against the actual results. Prediction is a similar but more general term. Forecasting might refer to specific formal statistical methods employing time series, cross-sectional or longitudinal data, or alternatively to less formal judgmental methods or the process of prediction and resolution itself. Usage can vary between areas of application: for example, in hydrology the terms "forecast" and "forecasting" are sometimes reserved for estimates of values at certain specific future times, while the term "prediction" is used for more general estimates, such as the number of times floods will occur over a long period. Risk and uncertainty are central to forecasting and prediction; it is generally considered a good practice to indicate the degree of uncertainty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forecasting
Forecasting is the process of making predictions based on past and present data. Later these can be compared (resolved) against what happens. For example, a company might estimate their revenue in the next year, then compare it against the actual results. Prediction is a similar but more general term. Forecasting might refer to specific formal statistical methods employing time series, cross-sectional or longitudinal data, or alternatively to less formal judgmental methods or the process of prediction and resolution itself. Usage can vary between areas of application: for example, in hydrology the terms "forecast" and "forecasting" are sometimes reserved for estimates of values at certain specific future times, while the term "prediction" is used for more general estimates, such as the number of times floods will occur over a long period. Risk and uncertainty are central to forecasting and prediction; it is generally considered a good practice to indicate the degree of uncertainty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Errors And Residuals In Statistics
In statistics and optimization, errors and residuals are two closely related and easily confused measures of the deviation of an observed value of an element of a statistical sample from its "true value" (not necessarily observable). The error of an observation is the deviation of the observed value from the true value of a quantity of interest (for example, a population mean). The residual is the difference between the observed value and the ''estimated'' value of the quantity of interest (for example, a sample mean). The distinction is most important in regression analysis, where the concepts are sometimes called the regression errors and regression residuals and where they lead to the concept of studentized residuals. In econometrics, "errors" are also called disturbances. Introduction Suppose there is a series of observations from a univariate distribution and we want to estimate the mean of that distribution (the so-called location model). In this case, the errors are th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calculating Demand Forecast Accuracy
Demand forecasting is known as the process of making future estimations in relation to customer demand over a specific period. Generally, demand forecasting will consider historical data and other analytical information to produce the most accurate predictions. More specifically, the methods of demand forecasting entails using predictive analytics of historical data to understand and predict customer demand in order to understand key economic conditions and assist in making crucial supply decisions to optimise business profitability. Demand forecasting methods are divided into two major categories, qualitative and quantitative methods. Qualitative methods are based on expert opinion and information gathered from the field. It is mostly used in situations when there is minimal data available to analyse. For example, when a business or product is newly being introduced to the market. Quantitative methods however, use data, and analytical tools in order to create predictions. Demand f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COVID-19 Pandemic
The COVID-19 pandemic, also known as the coronavirus pandemic, is an ongoing global pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The novel virus was first identified in an outbreak in the Chinese city of Wuhan in December 2019. Attempts to contain it there failed, allowing the virus to spread to other areas of Asia and later worldwide. The World Health Organization (WHO) declared the outbreak a public health emergency of international concern on 30 January 2020, and a pandemic on 11 March 2020. As of , the pandemic had caused more than cases and confirmed deaths, making it one of the deadliest in history. COVID-19 symptoms range from undetectable to deadly, but most commonly include fever, dry cough, and fatigue. Severe illness is more likely in elderly patients and those with certain underlying medical conditions. COVID-19 transmits when people breathe in air contaminated by droplets and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Monetary Fund
The International Monetary Fund (IMF) is a major financial agency of the United Nations, and an international financial institution, headquartered in Washington, D.C., consisting of 190 countries. Its stated mission is "working to foster global monetary cooperation, secure financial stability, facilitate international trade, promote high employment and sustainable economic growth, and reduce poverty around the world." Formed in 1944, started on 27 December 1945, at the Bretton Woods Conference primarily by the ideas of Harry Dexter White and John Maynard Keynes, it came into formal existence in 1945 with 29 member countries and the goal of reconstructing the international monetary system. It now plays a central role in the management of balance of payments difficulties and international financial crises. Countries contribute funds to a pool through a quota system from which countries experiencing balance of payments problems can borrow money. , the fund had XDR 477 billion (a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Shiller
Robert James Shiller (born March 29, 1946) is an American economist, academic, and author. As of 2019, he serves as a Sterling Professor of Economics at Yale University and is a fellow at the Yale School of Management's International Center for Finance. Shiller has been a research associate of the National Bureau of Economic Research (NBER) since 1980, was vice president of the American Economic Association in 2005, its president-elect for 2016, and president of the Eastern Economic Association for 2006–2007. He is also the co‑founder and chief economist of the investment management firm MacroMarkets LLC. Shiller was ranked by the ''IDEAS'' RePEc publications monitor in 2008 as among the 100 most influential economists of the world; and was still on the list in 2019. Eugene Fama, Lars Peter Hansen and Shiller jointly received the 2013 Nobel Memorial Prize in Economic Sciences, "for their empirical analysis of asset prices".* Background Shiller was born in Detroit, Michi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nouriel Roubini
Nouriel Roubini (born March 9 1958) is a Turkish-born Iranian-American economist. He is Professor Emeritus (2021–present) and was Professor of Economics (1995–2021) at the Stern School of Business, New York University, and also chairman of Roubini Macro Associates LLC, an economic consultancy firm. After receiving a BA in political economics at Bocconi University, Milan and a doctorate in international economics at Harvard University, he became an academic at Yale and a visiting researcher/advisor at the International Monetary Fund (IMF), the Federal Reserve, World Bank, and Bank of Israel. Much of his early research focused on emerging markets. During the administration of President Bill Clinton, he was a senior economist for the Council of Economic Advisers, later moving to the United States Treasury Department as a senior adviser to Timothy Geithner, who was Treasury Secretary under Barack Obama. Early life and education Nouriel Roubini was born in Istanbul, Turkey. When ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
