# WEIBULL

The `WEIBULL` function returns the Weibull distribution, which is a continuous probability distribution that is often used to model failure rates of systems over time. The function takes four arguments: `x`, which is the value at which to evaluate the distribution; `shape`, which is the shape parameter of the distribution; `scale`, which is the scale parameter of the distribution; and `cumulative`, which is a logical value indicating whether to return the cumulative distribution function (TRUE) or the probability density function (FALSE).

## Usage

Use the `WEIBULL` formula with the syntax shown below, it has 4 required parameters:

Parameters:
1. x (required):
The value at which to evaluate the distribution.
2. shape (required):
The shape parameter of the distribution. Must be greater than 0.
3. scale (required):
The scale parameter of the distribution. Must be greater than 0.
4. cumulative (required):
A logical value indicating whether to return the cumulative distribution function (TRUE) or the probability density function (FALSE).

## Examples

Here are a few example use cases that explain how to use the `WEIBULL` formula in Google Sheets.

### Calculating probability of failure

The `WEIBULL` function can be used to model the failure rate of a system and calculate the probability that the system will fail within a certain time frame.

### Analyzing reliability data

The `WEIBULL` function is often used in reliability engineering to analyze data on the failure rates of products over time.

### Fitting a distribution to data

The `WEIBULL` function can be used to fit a Weibull distribution to a set of data and evaluate how well the distribution fits the data.

## Common Mistakes

`WEIBULL` not working? Here are some common mistakes people make when using the `WEIBULL` Google Sheets Formula:

### Using a negative value for shape or scale

The shape and scale parameters of the Weibull distribution must be greater than 0. If you use a negative value for either parameter, the `WEIBULL` function will return an error.

### Using the wrong parameter order

Make sure you provide the `WEIBULL` function with the correct parameter order: x, shape, scale, cumulative. If you mix up the order of the parameters, the function will return an error.

The following functions are similar to `WEIBULL` or are often used with it in a formula:

• `NORMDIST`

The `NORMDIST` function in Google Sheets calculates the normal distribution for a specified value, mean, and standard deviation. It returns the probability of a value occurring within a specified range of a normal distribution. It is commonly used in statistics, finance, and science to analyze data and make predictions.

• `GAMMADIST`

The GAMMADIST function calculates the gamma distribution for a given set of parameters. The gamma distribution is a continuous probability distribution that is often used in statistics. It is commonly used to model the time between events. The function returns the probability density function or the cumulative distribution function for a given set of parameters.

• `EXPONDIST`

The `EXPONDIST` function calculates the probability of an event occurring at a specific time, assuming that the events follow an exponential distribution. It is commonly used in reliability analysis to model the time between failures of a system.

You can learn more about the `WEIBULL` Google Sheets function on Google Support.