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For the example data, the log-rank test for difference in survival gives a p-value of p=0.0653, indicating that the treatment groups do not differ significantly in survival, assuming an alpha level of 0.05. The sample size of 23 subjects is modest, so there is little power to detect differences
The difference between the two meanings of "extreme" appear when we consider a sequential hypothesis testing, or optional stopping, for the fairness of the coin. In general, optional stopping changes how p-value is calculated. [29] [30] Suppose we design the experiment as follows: Flip the coin twice. If both comes up heads or tails, end the ...
For example, a 100 Volt source with an of will deliver 250 watts of power to a load; reducing to increases the power delivered to 1000 watts. Note that this shows that maximum power transfer can also be interpreted as the load voltage being equal to one-half of the Thevenin voltage equivalent of the source.
The distributions of a wide variety of physical, biological, and human-made phenomena approximately follow a power law over a wide range of magnitudes: these include the sizes of craters on the moon and of solar flares, [2] cloud sizes, [3] the foraging pattern of various species, [4] the sizes of activity patterns of neuronal populations, [5] the frequencies of words in most languages ...
According to rules of thumb, this approximation is good if n ≥ 20 and p ≤ 0.05 [36] such that np ≤ 1, or if n > 50 and p < 0.1 such that np < 5, [37] or if n ≥ 100 and np ≤ 10. [38] [39] Concerning the accuracy of Poisson approximation, see Novak, [40] ch. 4, and references therein.
is greater than zero if and only if there is a temperature difference between the two thermal reservoirs. Since η max {\displaystyle \eta _{\text{max}}} is the upper limit of all reversible and irreversible heat engine efficiencies, it is concluded that work from a heat engine can be produced if and only if there is a ...
The LCL can be either computed or determined graphically using standard thermodynamic diagrams such as the skew-T log-P diagram or the tephigram.Nearly all of these formulations make use of the relationship between the LCL and the dew point, which is the temperature to which an air parcel needs to be cooled isobarically until its RH just reaches 100%.
The Student's t distribution plays a role in a number of widely used statistical analyses, including Student's t test for assessing the statistical significance of the difference between two sample means, the construction of confidence intervals for the difference between two population means, and in linear regression analysis.