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Parameters of a Lognormal Distribution Watch

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    I have been given this data, the heights of 16 different trees:

    9.8
    11.7
    18.6
    6.3
    4.9
    6.0
    15.2
    11.7
    9.5
    4.7
    6.9
    3.5
    4.0
    5.5
    6.2
    6.4

    How do you find the parameters of the lognormal distribution?

    I've messed about with it using some statistical software (minitab) and I get the lognormal distribution (ATTACHED). However this plot is not symmetrical so how could I possibly find the probability of a tree height below a certain height or above?

    Please help, I am stupid with stats
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    (Original post by LukeySherlock)
    I have been given this data, the heights of 16 different trees:

    9.8
    11.7
    18.6
    6.3
    4.9
    6.0
    15.2
    11.7
    9.5
    4.7
    6.9
    3.5
    4.0
    5.5
    6.2
    6.4

    How do you find the parameters of the lognormal distribution?

    I've messed about with it using some statistical software (minitab) and I get the lognormal distribution (ATTACHED). However this plot is not symmetrical so how could I possibly find the probability of a tree height below a certain height or above?

    Please help, I am stupid with stats
    Estimating the parameters with maximum-likelihood method
    \displaystyle \mu =\frac{\sum^n_{k=1}lnx_k}{n}
    \displaystyle \sigma^2 =\frac{\sum^n_{k=1}(lnx_k-\mu)^2}{n}
    if xi has lognormal distribution than ln(xi) has normal distribution with the same
    parameters.
 
 
 
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