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A-level Mathematics/OCR/S1/Discrete Random Variables
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Derived statistics
SYLABUS EXTRACT:
Understand, use and interpret different measures of central tendency (mean, median, mode) and variation (range, interquartile range, standard deviation), e.g. in comparing and contrasting sets of data;
Calculation of the mean and standard deviation of a set of data (including grouped data) either from the data itself or from given n totals such as Σx and Σx2, or Σ(x−a) and Σ(x−a)2.
Discrete random variables
SYLABUS EXTRACT:
(a) construct a probability distribution table relating to a given situation involving a discrete random variable X, and calculate the expectation, variance and standard deviation of X (the notations E(X ) for expectation (also referred to as expected value or mean) and Var(X ) for variance, are included);
(b) use formulae for probabilities for the binomial and geometric distributions, and model given situations by one of these, as appropriate (the notations B(n, p) and Geo( p) are included);
(c) use tables of cumulative binomial probabilities (or equivalent calculator functions);
(d) use formulae for the expectation and variance of the binomial distribution, and for the expectation of the geometric distribution.
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