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Fit probability distributions to data

MATLAB Toolstrip: On the

**Apps**tab, under**Math, Statistics and Optimization**, click the app icon.MATLAB command prompt: Enter

`distributionFitter`

.

`Data`

— Data to import from the workspacelist of variables | valid MATLAB expression

Specify the data to import by selecting a variable from the drop-down
list. If the variable is a matrix, the app imports the first column of the
matrix by default. To select a different column or row of the matrix, click
**Select Column or Row**. Alternatively, you can
enter any valid MATLAB expression in the field.

`Censoring`

— Variable containing censoring datalist of variables

Specify the censoring data by selecting a variable from the drop-down
list. If the variable is a matrix, the app imports the first column of the
matrix by default. To select a different column or row of the matrix, click
**Select Column or Row**. This parameter is
optional.

`Frequency`

— Variable containing frequency datalist of variables

Specify the frequency data by selecting a variable from the drop-down
list. If the variable is a matrix, the app imports the first column of the
matrix by default. To select a different column or row of the matrix, click
**Select Column or Row**. This parameter is
optional.

`Data set name`

— Data set nametext

Enter a name for the data set or accept the default name.

`Manage data sets`

— Manage previously imported data setslist of data sets

Manage previously imported data sets. Click the data set of interest, then
click the buttons below this pane to view the data
(**View**), set the bin rules (**Set Bin
Rules**), rename the data set (**Rename**),
or delete the data set (**Delete**).

`Data preview`

— Preview plot of datahistogram plot

Display a preview plot of the variable selected from the
**Data** drop-down menu.

`Fit name`

— Name of fittext

Enter a name for the fit or accept the default name.

`Data`

— Data set to fitlist of data sets

Specify the data to fit by selecting a data set from the drop-down list.

`Distribution`

— Distribution to fit`Normal`

(default) | `Exponential`

| `Weibull`

| `Non-parametric`

| `...`

Specify the distribution to fit by selecting a distribution name from the drop-down list.

`Exclusion rule`

— Data exclusion rulelist of exclusion rules

Specify a rule to exclude some data values by selecting an exclusion rule
from the drop-down list. To populate this drop-down list, you must first
define exclusion rules by clicking **Exclude** in the
main window of the app. This parameter is optional

`Plot`

— Flag to plot fitted distributionchecked (default) | unchecked

Specify which fit or fits to plot in the main window by selecting the
**Plot** check box next to each fit. Clear the
**Plot** check box to remove a fit from the
plot.

`Conf bounds`

— Flag to plot confidence boundsunchecked (default) | checked

If you select **Plot** for a particular fit, you can
select **Conf bounds** to display the confidence bounds for
that fit on the plot in the main window. Clearing the **Conf
bounds** check box removes the confidence intervals from the
plot. The Distribution Fitter app displays confidence bounds only if the
Display Type in the main window is set to **Cumulative probability
(CDF)**, **Quantile (inverse CDF)**,
**Survivor function**, or **Cumulative
hazard**.

`Fit`

— Fit to evaluatelist of fits

Select one or more fits from the list to evaluate.

`Function`

— Available functions to fit`Density (PDF)`

(default) | `Cumulative probability (CDF)`

| `Quantile (inverse CDF)`

| `Survivor function`

| `Cumulative hazard`

| `Hazard rate`

Specify the type of probability function to evaluate from the drop-down list. Available probability functions include the probability density function (pdf), cumulative distribution function (cdf), quantile (inverse cdf), survival function, cumulative hazard, and hazard rate.

`At x =`

— Values at which to evaluate functionnumeric vector

Specify a numeric vector of values at which to evaluate the function. If
you specify **Function** as **Quantile
(inverse CDF)**, this field name changes to **At p
=** and you enter a vector of probability values.

`Compute confidence bounds`

— Flag to compute confidence boundsunchecked (default) | checked

Select **Compute confidence bounds** to compute the
confidence bounds for the selected fit. This check box is enabled only if
you specify **Function** as **Cumulative
probability (CDF)**, **Quantile (inverse
CDF)**, **Survivor function**, or
**Cumulative hazard**. This parameter is
optional.

`Level`

— Level for confidence bounds95% (default) | numeric value

Specify the level at which to compute the confidence bounds. This check
box is enabled only if you specify **Function** as
**Cumulative probability (CDF)**, **Quantile
(inverse CDF)**, **Survivor function**, or
**Cumulative hazard**.

`Plot function`

— Flag to plot functionunchecked (default) | checked

Select **Plot function** to display a plot of the
distribution function, evaluated at the points that you enter in the
**At x =** field, in a new window. This parameter
is optional.

`Exclusion rule name`

— Name of exclusion ruletext

Enter a name for the exclusion rule.

`Exclude sections`

— Define data exclusion rules numericallynumeric value

Specify lower and upper limits for the data numerically.

`Exclude graphically`

— Define data exclusion rules graphicallylist of variables

Specify lower and upper limits for the data by selecting a variable from
the **Select data** drop-down list and clicking
**Exclude Graphically**. An interactive plot
opens in a new window, where you can add lower or upper limits by clicking
and dragging a boundary on the plot.

`Existing exclusion rules`

— List of existing exclusion ruleslist of exclusion rules

Select an existing exclusion rule from the list. You can copy, view, rename, or delete exclusion rules by clicking the appropriate button.