Curtis Miller

Modeling and simulation (M&S) validation for operational testing often involves comparing live data with simulation outputs. Statistical methods known as functional data analysis (FDA) provides techniques for analyzing large data sets (“large” meaning that a single trial has a lot of information associated with it), such as radar tracks. We preview how FDA methods could assist M&S validation by providing statistical tools handling these large data sets. This may facilitate analyses that make use of more of the data available and thus allows for better detection of differences between M&S predictions and live test results....

How many success-or-failure observations should we collect from a computer simulation? Often, researchers use space-filling design of experiments when planning modeling and simulation (M&S) studies. We are not satisfied with existing guidance on justifying the number of runs when developing these designs, either because the guidance is insufficiently justified, does not provide an unambiguous answer, or is not based on optimizing a statistical measure of merit. Analysts should use confidence interval margin of error as the statistical measure of merit for M&S studies intended to characterize overall M&S behavioral trends....

Logistic regression is a commonly-used method for analyzing tests with probabilistic responses in the test community, yet calculating power for these tests has historically been challenging. This difficulty prompted the development of methods based on signal-to-noise ratio (SNR) approximations over the last decade, tailored to address the intricacies of logistic regression’s binary outcomes. However, advancements and improvements in statistical software and computational power have reduced the need for such approximate methods....

This work describes the development of a statistical test created in support of ongoing verification, validation, and accreditation (VV&A) efforts for modeling and simulation (M&S) environments. The test computes a Wald-type statistic comparing two generalized linear models estimated from live test data and analogous simulated data. The resulting statistic indicates whether the M&S outputs differ from the live data. After developing the test, we applied it to two logistic regression models estimated from live torpedo test data and simulated data from the Naval Undersea Warfare Center’s Environment Centric Weapons Analysis Facility (ECWAF)....

We discuss four areas in which statistically rigorous methods contribute to modeling and simulation validation studies. These areas are statistical risk analysis, space-filling experimental designs, metamodel construction, and statistical validation. Taken together, these areas implement DOT&E guidance on model validation. In each area, IDA has contributed either research methods, user-friendly tools, or both. We point to our tools on testscience.org, and survey the research methods that we’ve contributed to the M&S validation literature...

This is a briefing intended to motivate and explain the basic concepts of applying statistics to verification and validation. The briefing will be presented at the Navy M&S VV&A WG (Sub-WG on Validation Statistical Method Selection). Suggested Citation Pagan-Rivera, Keyla, John T Haman, Kelly M Avery, and Curtis G Miller. Statistical Methods for M&S V&V: An Intro for Non- Statisticians. IDA Product ID-3000770. Alexandria, VA: Institute for Defense Analyses, 2024....

Version control software manages, archives, and (optionally) distributes different versions of files. The most popular program for version control is Git, which serves as the backbone of websites such as Github, Bitbucket, and others. In this mini- tutorial, we will introduce basics of version control in general, and Git in particular. We explain what role Git plays in a reproducible research context. The goal of the course is to get participants started using Git....

Modeling and simulation (M&S) outputs help the Director, Operational Test and Evaluation (DOT&E) assess the effectiveness, survivability, lethality, and suitability of systems. To use M&S outputs, DOT&E needs models and simulators to be sufficiently verified and validated. The purpose of this paper is to improve the state of verification and validation by recommending and demonstrating a set of statistical techniques—metamodels, also called statistical emulators—to the M&S community. The paper expands on DOT&E’s existing guidance about metamodel usage by creating methodological recommendations the M&S community could apply to its activities....

This document presents arguments and methods for using space-filling designs (SFDs) to plan modeling and simulation (M&S) data collection. Suggested Citation Avery, Kelly, John T Haman, Thomas Johnson, Curtis Miller, Dhruv Patel, and Han Yi. Test Design Challenges in Defense Testing. IDA Product ID 3002855. Alexandria, VA: Institute for Defense Analyses, 2024. Slides: Paper: