enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. False positives and false negatives - Wikipedia

    en.wikipedia.org/wiki/False_positives_and_false...

    Despite the fact that the likelihood ratio in favor of the alternative hypothesis over the null is close to 100, if the hypothesis was implausible, with a prior probability of a real effect being 0.1, even the observation of p = 0.001 would have a false positive rate of 8 percent. It wouldn't even reach the 5 percent level.

  3. False positive rate - Wikipedia

    en.wikipedia.org/wiki/False_positive_rate

    The false positive rate is calculated as the ratio between the number of negative events wrongly categorized as positive (false positives) and the total number of actual negative events (regardless of classification). The false positive rate (or "false alarm rate") usually refers to the expectancy of the false positive ratio.

  4. One- and two-tailed tests - Wikipedia

    en.wikipedia.org/wiki/One-_and_two-tailed_tests

    p-value of chi-squared distribution for different number of degrees of freedom. The p-value was introduced by Karl Pearson [6] in the Pearson's chi-squared test, where he defined P (original notation) as the probability that the statistic would be at or above a given level. This is a one-tailed definition, and the chi-squared distribution is ...

  5. p-value - Wikipedia

    en.wikipedia.org/wiki/P-value

    If we use the test statistic /, then under the null hypothesis is exactly 1 for two-sided p-value, and exactly / for one-sided left-tail p-value, and same for one-sided right-tail p-value. If we consider every outcome that has equal or lower probability than "3 heads 3 tails" as "at least as extreme", then the p -value is exactly 1 / 2 ...

  6. 68–95–99.7 rule - Wikipedia

    en.wikipedia.org/wiki/68–95–99.7_rule

    Refined models should then be considered, e.g. by the introduction of stochastic volatility. In such discussions it is important to be aware of the problem of the gambler's fallacy , which states that a single observation of a rare event does not contradict that the event is in fact rare.

  7. q-value (statistics) - Wikipedia

    en.wikipedia.org/wiki/Q-value_(statistics)

    If we control the pFDR to 0.05 by considering all genes with a q-value of less than 0.05 to be differentially expressed, then we expect 5% of the positive results to be false positives (e.g. 900 true positives, 45 false positives, 100 false negatives, 8,955 true negatives). This strategy enables one to obtain relatively low numbers of both ...

  8. Statistical hypothesis test - Wikipedia

    en.wikipedia.org/wiki/Statistical_hypothesis_test

    For every card, the probability (relative frequency) of any single suit appearing is 1/4. If the alternative is valid, the test subject will predict the suit correctly with probability greater than 1/4. We will call the probability of guessing correctly p. The hypotheses, then, are:

  9. G-test - Wikipedia

    en.wikipedia.org/wiki/G-test

    Note: Fisher's G-test in the GeneCycle Package of the R programming language (fisher.g.test) does not implement the G-test as described in this article, but rather Fisher's exact test of Gaussian white-noise in a time series. [10] Another R implementation to compute the G statistic and corresponding p-values is provided by the R package entropy.