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  2. Simple linear regression - Wikipedia

    en.wikipedia.org/wiki/Simple_linear_regression

    Since the data in this context is defined to be (x, y) pairs for every observation, the mean response at a given value of x, say x d, is an estimate of the mean of the y values in the population at the x value of x d, that is ^ ^. The variance of the mean response is given by: [11]

  3. Expected value - Wikipedia

    en.wikipedia.org/wiki/Expected_value

    In probability theory, the expected value (also called expectation, expectancy, expectation operator, mathematical expectation, mean, expectation value, or first moment) is a generalization of the weighted average. Informally, the expected value is the mean of the possible values a random variable can take, weighted by the probability of those ...

  4. Data valuation - Wikipedia

    en.wikipedia.org/wiki/Data_valuation

    Where income from data is realized through trading data in a marketplace, there are further limitations, as markets fail to describe the full option value of data, and usually lack enough buyers and sellers for the market to settle on a price that truly reflects the economic value of the data. Cost based valuations measure the cost to create ...

  5. Positive and negative predictive values - Wikipedia

    en.wikipedia.org/wiki/Positive_and_negative...

    The positive predictive value (PPV), or precision, is defined as = + = where a "true positive" is the event that the test makes a positive prediction, and the subject has a positive result under the gold standard, and a "false positive" is the event that the test makes a positive prediction, and the subject has a negative result under the gold standard.

  6. Moving average - Wikipedia

    en.wikipedia.org/wiki/Moving_average

    Smoothing of a noisy sine (blue curve) with a moving average (red curve). In statistics, a moving average (rolling average or running average or moving mean [1] or rolling mean) is a calculation to analyze data points by creating a series of averages of different selections of the full data set.

  7. Mean - Wikipedia

    en.wikipedia.org/wiki/Mean

    The mean of a set of observations is the arithmetic average of the values; however, for skewed distributions, the mean is not necessarily the same as the middle value (median), or the most likely value (mode). For example, mean income is typically skewed upwards by a small number of people with very large incomes, so that the majority have an ...

  8. Mean absolute error - Wikipedia

    en.wikipedia.org/wiki/Mean_absolute_error

    Quantity difference exists when the average of the X values does not equal the average of the Y values. Allocation difference exists if and only if points reside on both sides of the identity line. [ 4 ] [ 5 ]

  9. Mean of a function - Wikipedia

    en.wikipedia.org/wiki/Mean_of_a_function

    In calculus, and especially multivariable calculus, the mean of a function is loosely defined as the average value of the function over its domain. In one variable, the mean of a function f(x) over the interval (a,b) is defined by: [1] ¯ = ().