Kolmogorov-Smirnof test for lognormal distribution with estimated parameters
Hi, I believe that to performe KS test parameters must not be estimated by sample data. Despite some advantages, the KS test has several important limitations: 1. It only applies to continuous distributions. 2. It tends to be more sensitive near the center of the distribution than at the tails. -->3. Perhaps the most serious limitation is that the distribution must be fully specified. That is, if location, scale, and shape parameters are estimated from the data, the critical region of the K-S test is no longer valid. It typically must be determined by simulation. <-- Due to limitations 2 and 3 above, many analysts prefer to use the Anderson-Darling goodness-of-fit test. However, the Anderson-Darling test is only available for a few specific distributions. See: http://www.itl.nist.gov/div898/handbook/eda/section3/eda35g.htm for KS test http://www.itl.nist.gov/div898/handbook/eda/section3/eda35e.htm for Anderson-Darling test http://www.itl.nist.gov/div898/handbook/eda/section3/eda35f.htm X2 test I suggest you to use th chisquare test. Hoping to help you. Best, Vito
You wrote:
Hello all,
Would somebody be kind enough to show me how to do a
KS test in R for a lognormal distribution with
ESTIMATED parameters. The R function ks.test()says
"the parameters specified must be prespecified and not
estimated from the data" Is there a way to correct
this when one uses
estimated data?
Regards,
Kwabena.
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