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This is a list of countries by external debt: it is the total public and private debt owed to nonresidents repayable in internationally accepted currencies, goods or services, where the public debt is the money or credit owed by any level of government, from central to local, and the private debt the money or credit owed by private households or private corporations based on the country under ...
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Timeline of the top 5 countries. The five countries with the largest foreign exchange reserves almost all have reserves of at least 500 billion USD and higher and have maintained such an amount for at least a week. At present there are only six countries whose reserves are at such a figure; this includes China, Japan, Switzerland, India, Russia ...
- Introduction
- Definition
- Imbalanced Data
- F-Measure
- Limitations as Goals
- See Also
- External Links
In a classification task, the precision for a class is the number of true positives (i.e. the number of items correctly labelled as belonging to the positive class) divided by the total number of elements labelled as belonging to the positive class (i.e. the sum of true positives and false positives, which are items incorrectly labelled as belongin...
For classification tasks, the terms true positives, true negatives, false positives, and false negatives (see Type I and type II errors for definitions) compare the results of the classifier under test with trusted external judgments. The terms positive and negative refer to the classifier's prediction (sometimes known as the expectation), and the ...
Accuracy can be a misleading metric for imbalanced data sets. Consider a sample with 95 negative and 5 positive values. Classifying all values as negative in this case gives 0.95 accuracy score. There are many metrics that don't suffer from this problem. For example, balanced accuracy(bACC) normalizes true positive and true negative predictions by ...
A measure that combines precision and recall is the harmonic meanof precision and recall, the traditional F-measure or balanced F-score: This measure is approximately the average of the two when they are close, and is more generally the harmonic mean, which, for the case of two numbers, coincides with the square of the geometric mean divided by the...
There are other parameters and strategies for performance metric of information retrieval system, such as the area under the ROC curve (AUC) or pseudo-R-squared.
The number π (/paɪ/; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. The number π appears in many formulae across mathematics and physics. It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although ...
Exceptionally, the golden ratio is equal to the limit of the ratios of successive terms in the Fibonacci sequence and sequence of Lucas numbers: [42] φ. In other words, if a Fibonacci and Lucas number is divided by its immediate predecessor in the sequence, the quotient approximates . For example, and.
4K resolution refers to a horizontal display resolution of approximately 4,000 pixels. Digital television and digital cinematography commonly use several different 4K resolutions. In television and consumer media, 3840 × 2160 (4K UHD) with a 16:9 aspect ratio is the dominant 4K standard, whereas the movie projection industry uses 4096 × 2160 (DCI 4K).
