JMAT_V4_N4_RP1 James Edward Osler II Journal on Mathematics 2277-5137 4 4 1 8 Educational Science, Invariant, Inventive Investigative Instruments, Mathematical Models, Psychometrics, Researcher Decision Rule, Research Engineering, Trichotomous Psychometrics, Trichotomous Testing Input, Trichotomous Testing Output, Trichotomy, Trifold Assessment, Tri-Squared Computational, Tri-Squared Test This monograph provides an in-depth discourse on a model for the design and construction of digital instruments in the field of Educational Science first detailed in i-managers Journal on Mathematics earlier article. A research engineered computational instrument design model involves the methodology and the metrics used to conduct in-depth research investigations via the innovative Total Transformative Trichotomy-Squared (Tri-Squared) Test. The completion of digital instrumentation of the Tri–Squared will provide researchers with a means of creating qualitative metrics that can be qualitatively analyzed. The creation of a model of digital instruments based on Tri-Squared calculation presents a novel method for in-depth mixed methods research design based upon “Trichotomous Psychometric”. Trichotomous Psychometrics involves the development, deployment, and analysis of Trifold assessments for the holistic transformation of qualitative outcomes into quantitative data. This paper is a continuation of the published article entitled, “The Psychometrics of Educational Science: Designing Trichotomous Inventive Investigative Instruments for Qualitative and Quantitative for Inquiry” published in the i-managers Journal on Education Psychology. October - December 2015 Copyright © 2015 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=3695