lognormal distribution

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log·nor·mal dis·tri·bu·tion

if a variable y is such that x = log y, it is said to have a lognormal distribution; this is a skew distribution.
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Caption: Figure 7: Comparison between empirical distribution of the input power delivered to the mobile phone during pure NLOS scenario and a log-normal distribution.
To model the reporting delay for each disease, we fitted analytical log-normal distributions to the OSIRIS data.
For this reason, [18] and [19] resort to the log-normal distribution, and use it to approximate the Gamma-log-normal distribution in (6) and derive the closed-form PDF of [p.sub.i].
three-parameter shifted lognormal distributions [1], the truncated-stable distributions considering three types of secondary spatial reuse protocols [3], the log-normal distribution under power control and contention control [4], the symmetric stable distributions [6], the Levy distribution for some conditions [7], and the Gaussian distribution [2].
In order to account for variations in the sensitivity of the cells to radiation, one could assume that the individual radiation sensitivity of the cells in a population follows a given log-normal distribution [12].
The log-logistic (LL) distribution is widely used in practice And it is an alternative to the log-normal distribution since it presents a failure rate function that increases, reaches a peak after some finite period, and then declines gradually.
Furthermore, the free-flow travel time distribution of the highway from the peripheral parking lots to the destination is assumed to follow a log-normal distribution.
where: D is the specific distribution form of [lambda], such as normal, uniform or log-normal distribution; n and a are the mean and standard deviation of [lambda], respectively.
The clustering of FZI data is performed on the basis of the logarithm of FZI values because the FZI values calculated from actual field data usually exhibit a log-normal distribution. Because the FZI distribution is a superposition of multiple log-normal distributions, a histogram of log FZI values should show N number of normal distributions for N number of HFUs.
The median normal deviation of the log-normal distribution ([sigma]) was calculated from the median [CV.sub.t] (as a decimal value), as: [sigma] = [[square root of ([CV.sup.2.sub.t] + 1)] (Eq.
Therefore, log-normal distribution was selected as a suitable model to represent data sets for motorized 2-wheelers.