Features Common to Weibull++ and ALTA

Many of your favorite features are available for both Weibull++ and ALTA analyses. Some of these features include:

Plots and Charts to Visualize Your Analysis Results

Weibull++ and ALTA make it easy to create a complete array of plots and charts to present analysis information graphically. The Plot Setup allows you to completely customize the "look and feel" of plot graphics while the RS Draw metafile graphics editor provides the option to insert text, draw objects or mark particular points on plot graphics. You can save your plots in a variety of graphic file formats (*.jpg, *.gif, *.png or *.wmf) for use in other documents.

Overlay Plots (formerly called "MultiPlots") allow you to plot the results from multiple data sets together in the same plot. This can be an effective visual tool for many different applications, such as comparing different data sets or analysis methods (e.g., Design A vs. Design B or MLE vs. Rank Regression) or demonstrating the effects of a design change (e.g., Before vs. After).

The Side-by-Side Plots utility allows you to view (and print) multiple plots for a given data set side-by-side. For example, you may want to show the probability, reliability, pdf and failure rate plots for a given analysis together in the same window. Alternatively, you may wish to compare the probability or pdf plots for a given data set when analyzed with different distributions/models.

Monte Carlo Simulation

As described in Monte Carlo and SimuMatic, both Weibull++ and ALTA continue to use Monte Carlo simulation for generating data sets that can be analyzed directly in a standard folio. You can also use the SimuMatic® utilities to automatically perform a large number of reliability analyses on data sets that have been created via simulation. These simulated data sets and calculated results can be used to perform a wide variety of reliability tasks, such as:

Experimenting with the influence of sample sizes and censoring schemes on analysis methods.
Constructing simulation-based confidence bounds.
Experimenting with confidence intervals for analyses performed with different distributions.
Developing and evaluating test plans.
Utilizing user-defined equations for risk analysis and probabilistic design.

Stress-Strength Calculator and Life Comparison Test

As described in Tests of Comparison, Weibull++ and ALTA provide two tools designed for statistical comparison of data sets. The Life Comparison tool allows you to compare two data sets to determine whether items from the first set will outlast those of the second. The Stress-Strength comparison tool uses the same statistical approach to determine the probability of failure based on the probability of a specified "stress" data set exceeding a specified "strength" data set. Both tools have been redesigned and enhanced in the Synthesis version.

Reliability Block Diagrams (RBDs) for Failure Modes Analysis

A simple Competing Failure Modes (CFM) analysis can be performed directly within the Weibull++ standard folio by assuming a series reliability model and using only one type of distribution to analyze all the modes. When a more complex analysis is required, you can use the reliability block diagram (RBD) feature that is directly integrated into Weibull++ and ALTA projects. The blocks in the diagram are linked directly to analyzed standard folios and you can use the RBD in any or all of the following situations:

The analysis involves more than four failure modes.
The failure modes are described by different life distributions.
The relationship between the failure modes does not follow a series configuration. For example, if more than one failure mode must occur together in order for the component to fail, a parallel configuration must be used for the analysis and this is referred to as "complex failure modes analysis" rather than "competing failure modes analysis."

Workbooks and Reports for Custom Analysis

All Synthesis applications offer several powerful tools for custom analysis and reporting.

If you need a quick way to perform additional calculations that are associated with a particular analysis, you can insert any number of General Spreadsheets into any Weibull++ or ALTA standard folio.
If you want to create a custom analysis or report that integrates results from different analysis folios, the Synthesis version provides a choice of using an Analysis Workbook (with functionality similar to Microsoft Excel) or a new Word Report Template (with functionality similar to Microsoft Word).

All three tools allow you to use the Function Wizard to automatically insert calculated results based on selected data sheets. With the workbooks and report templates, you also have the option to configure the functions to use generically numbered "data sources" instead of named data sheets. This makes it easy to use the same template again for different data sets.

Quick Parameter Estimator (QPE)

The Quick Parameter Estimator (formerly called the "Parameter Experimenter") allows you to estimate the parameters of a statistical model based on what you know about the behavior over time. With the Weibull++ utility, you can solve for one parameter of the distribution if you provide one data point and the other parameter(s), or solve for all parameters if you provide two data points. The ALTA version allows you to incorporate information about the life at the accelerated stress levels in order to estimate the missing parameters of the entire model (i.e., life-stress relationship and use-level life distribution).

Quick Statistical Reference (QSR)

The Quick Statistical Reference frees you from tedious lookups in tables by quickly returning results for commonly used statistical functions. Results include Median Ranks, Chi-Squared Values, Cumulative Binomial Probability, and many more. There is also a Polynomial Interpolation Function that allows you to enter known data points and then calculate Y for any given X value.

Non-Linear Equation Fit Solver and Root Finder

Weibull++ and ALTA continue to offer two familiar statistical tools for working with non-linear equations.

The Non-Linear Equation Fit Solver allows you to estimate the parameters of any user-defined non-linear equation. This gives you the flexibility to perform simple parameter estimation on statistical models other than the life distributions and life-stress relationship models available in standard folios. After you have solved the equation, the tool provides a plot to visualize how the data fit the function, and also makes it easy to calculate Y for any given X value.
The Non-Linear Equation Root Finder allows you to quickly solve for the root of any user-defined non-linear equation. This helps you eliminate some of the guesswork of solving for the value of the unknown variable that makes the function be as close to zero as possible.