The EXPON.DIST function in Google Sheets is used to model the exponential distribution, which is commonly applied in scenarios that involve waiting times or the time until an event occurs. This function allows users to compute the probability of a given time interval using a specified rate parameter, LAMBDA. Understanding how to use this function can be valuable for statistical analysis, particularly in fields such as queuing theory and reliability engineering.

Syntax

EXPON.DIST(x, lambda, cumulative)

• x: The value at which you want to evaluate the distribution.
• lambda: The rate parameter of the distribution, indicating how often events occur.
• cumulative: A boolean value that indicates whether to calculate the cumulative distribution function (TRUE) or the probability density function (FALSE).

Example #1

EXPON.DIST(1, 0.5, FALSE)

This function calculates the probability density for an event occurring at exactly 1 time unit when the average rate (LAMBDA) is 0.5. The result would be 0.5, indicating this is the density at that specific point.

Example #2

EXPON.DIST(3, 0.2, TRUE)

This example computes the cumulative probability that an event occurs within 3 time units when the rate of occurrence is 0.2. The output may be approximately 0.524, signifying about a 52.4% chance of the event happening within that interval.

Example #3

EXPON.DIST(2, 1, FALSE)

In this case, it calculates the probability density for an event at exactly 2 time units with a LAMBDA of 1. The result will be around 0.183, showing the density at that specific time.

Error handling

• NUM!: Occurs when the LAMBDA value is less than or equal to 0 or when x is negative, indicating invalid parameters.
• VALUE!: Triggered when the input for LAMBDA or cumulative is of the wrong type, requiring numeric or Boolean values.

Conclusion

The EXPON.DIST function is an essential tool for statistical analysis in Google Sheets, especially for modeling waiting times and event occurrences. By understanding its syntax and the significance of its parameters, users can effectively leverage this function to gain insights into probability distributions. Mastering EXPON.DIST can significantly enhance decision-making processes based on statistical data.