Chapter 4: Reliability Test Design (RTD) Module

This Reliability Test Design module was developed to determine if the product reliability can meet the desired requirements, and includes the following methods: Non-Parametric Binomial, Parametric Binomial and Chi-Squared. 

Using, for example, the Non-Parametric Binomial, the user can determine the reliability of an item which has an instantaneous actuation, and therefore must be treated as discrete variables. The Non-Parametric Binomial can also be applied in situations where the item has presented no failures.

4.1 RTD Analysis List

On the main page, the RTD module can be accessed through the dashboard under the item “Reliability Test Design” or on the main menu tab, by clicking on RTD -> My Analysis.


The RTD analysis and items will also be displayed on the dashboard’s chart, along with other analyses    and stored in the account.


The RTD analysis list follows the same rules as the previous features:


As this menu is identical to all other access menus in R4All modules, an explanation of its features will be omitted here (for more details about the analysis list, see chapter 2.1 LDA – Analysis List).

4.2 RTD – Reliability Test Design Inputs

Different from the other modules, the RTD module has no settings, as these methods follow strict statistic formulation, applied to discrete variables. That’s also the reason why this module has no plotting, as graphs can be drawn to continuous probability variables.

The methods used in R4All to stablish a relation between reliability over operation/test time, sample size, confidence bounds, and number of failures are the Non-Parametric Binomial, the Parametric Binomial and Chi-Squared.

Non-Parametric Binomial


Parametric Binomial