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Lognormal parameter estimates

`pHat = lognfit(x)`

`[pHat,pCI] = lognfit(x)`

`[pHat,pCI] = lognfit(x,alpha)`

`[___] = lognfit(x,alpha,censoring)`

`[___] = lognfit(x,alpha,censoring,freq)`

`[___] = lognfit(x,alpha,censoring,freq,options)`

`[___] = lognfit(`

specifies whether each value in `x`

,`alpha`

,`censoring`

)`x`

is right-censored or not. Use the
logical vector `censoring`

in which 1 indicates observations that are
right-censored and 0 indicates observations that are fully observed. With censoring, the
`phat`

values are the maximum likelihood estimates (MLEs).

To compute the confidence intervals, `lognfit`

uses the exact method
for uncensored data and the Wald method for censored data. The exact method provides exact
coverage for uncensored samples based on *t* and chi-square
distributions.

`lognfit`

is a function specific to lognormal distribution.
Statistics and Machine Learning Toolbox™ also offers the generic functions `mle`

, `fitdist`

, and `paramci`

and the **Distribution Fitter** app, which support various
probability distributions.

`mle`

returns MLEs and the confidence intervals of MLEs for the parameters of various probability distributions. You can specify the probability distribution name or a custom probability density function.Create a

`LognormalDistribution`

probability distribution object by fitting the distribution to data using the`fitdist`

function or the**Distribution Fitter**app. The object properties`mu`

and`sigma`

store the parameter estimates. To obtain the confidence intervals for the parameter estimates, pass the object to`paramci`

.

[1] Evans, M., N. Hastings, and B.
Peacock. *Statistical Distributions*. 2nd ed. Hoboken, NJ: John Wiley
& Sons, Inc., 1993.

[2] Lawless, J. F.
*Statistical Models and Methods for Lifetime Data*. Hoboken, NJ:
Wiley-Interscience, 1982.

[3] Meeker, W. Q., and L. A. Escobar.
*Statistical Methods for Reliability Data*. Hoboken, NJ: John Wiley
& Sons, Inc., 1998.

`LognormalDistribution`

| `fitdist`

| `logncdf`

| `logninv`

| `lognlike`

| `lognpdf`

| `lognrnd`

| `lognstat`

| `mle`

| `paramci`

| `statset`