The Lectical Assessment System

A new kind of measure

The Computerized Lectical Assessment System (CLAS) represents a paradigm shift in educational measurement, making it possible, for the first time, to continuously track cognitive growth across the verbal lifespan, in any domain of knowledge. CLAS literally functions as a universal, content-neutral developmental ruler, used to measure the complexity-level of texts from any knowledge domain on a single developmental scale. 

CLAS is both standardized and prescriptive. Patterns in texts are compared to a set of 802 idealized patterns. High fit to the best fitting pattern not only provides a score, but indicates an optimal pattern of development. Low fit, on the other hand, can indicate developmental problems.

CLAS enables assessment-free measurement that not only generates highly reliable and informative growth records for learners, but also helps educators identify learners who are not growing optimally.

Developing CLAS

For decades, test developers attempted to create a generalized electronic scoring system for texts. AI-based solutions have made some inroads, but like the electronic scoring systems now being produced by educational test developers, they measure easily quantified aspects of texts (like vocabulary, word associations, sentence structure, and punctuation) rather than what we really want to know—whether or not we are providing optimal support for the development of the agile, well-developed minds required to thrive in our rapidly changing, crisis-ridden world.

CLAS (Now also called the Lectical Assessment System) is unique. It's a truly general system that can readily be adapted for use in any knowledge domain that involves reflective thought. Rather than measuring aspects of texts that are easily quantified, CLAS measures growth along a well-validated developmental scale called the Lectical^® Scale. When CLAS produces a score, it tells us where a particular text lands on this scale. Scores range from 600 to 1400, covering the verbal lifespan.

CLAS scoring criteria are based on the human analysis of more than 50,000 texts. At its core is the Lectical^™ Dictionary—the world's first developmental dictionary—a constantly evolving curated taxonomy of meanings. (More about the Dictionary below.)

CLAS can be used:

• to score texts of all kinds,
• to evaluate the effectiveness of interventions designed to promote mental development,
• to track development over time,
• to trace conceptual development,
• in comparative research on conceptual development, and
• in research on developmental processes.

CLAS has several other benefits:

1. It makes it possible, for the first time, to conduct measure developemnt at any scale,
2. It is easily expandable into new knowledge domains,
3. It is far more accurate than human scorers,
4. It is entirely objective, and
5. It dramatically reduces the cost of scoring large numbers of assessments.

Since its initial introduction in 2014, CLAS has been used to score thousands of assessments for numerous research and evaluation projects. In its final standardized version, it has fully replaced the human version of the Lectical Assessment System.

The Lectical Dictionary

The Lectical Dictionary is at the core of everything we do here at Lectica. It not only makes CLAS possible, but also helps us describe learning sequences and develop learning resources like Micro-VCoL Makers™, and our newest and most groundbreaking product, MindLog™.

The Lectical Dictionary is composed of units of meaning called "Lectical Items"—words or phrases like "evidence" and "evidence-based" that carry word-like meaning. Each Lectical Item is assigned to a Lectical Phase (1/4 of a Lectical Level), based on a combination of empirical evidence, the judgment of our analysts, and a variety of helper algorithms. The goal is to assign items to the lowest level at which the simplest meaning they carry is likely to be useful.

For example, an examination of items containing the word evidence reveals easily observed progressions in the development of its meaning, such as the following:

• Phase 09b: something that I know is true
• Phase 09c: good information that comes from something people have seen or proved (same as a fact)
• Phase 09d: more or less proven facts that you can use to persuade others
• Phase 10a: information that comes from good research and can be used to support arguments
• Phase 10b: information that comes from different kinds of research and sources and needs to be evaluated before you use it to support arguments

Lectical Dictionary entries begin with first speech and cover the full span of development. In addition to being assigned to a Lectical Phase, many of the items in the Lectical Dictionary have been assigned to thematic strands such as deliberation, conflict resolution, the physics of energy, or evidence. For example, at this writing, over 5,000 terms in the Lectical Dictionary relate to evidence in some way. Longitudinal and cross-sectional analyses of sequences like the evidence sequence have demonstrated that each successive conception builds upon previous conceptions (Dawson & Gabrielian, 2003; Dawson- Tunik, 2004). These findings are entirely consistent with the developmental theory upon which the dictionary is based (Fischer, 1980; Piaget, 1985), and suggest that Lectical Items assigned to a particular phase can be said not only to represent the understandings of that phase but also play the role of building blocks for future conceptions. Because of this, when we look at the density distribution of Lectical Items across phases within a given performance, we are to some extent, looking at the historical pattern of an individual’s development.

The rate of Dictionary development has increased as what we learn about patterns in the acquisition of meanings is gradually integrated into our methods and technology. For example, we have learned that there are regularities in the progression of verb conjugation within particular developmental levels and that, in some cases, new single-word Lectical Items typically don’t appear next to some conjunctions until the phase following the phase to which they have been assigned. When adequately regular, patterns like these allow a degree of automation in the curation process. (We call this process lexicating™.) The Lectical Dictionary is continuously monitored, refined, and added to by trained analysts. As we build new assessments in new subject areas, the Lectical Dictionary is becoming an increasingly comprehensive curated taxonomy of meanings.

CLAS is not a form of AI. Even now, its ongoing maintenance and development requires a great deal of expert human judgment. In fact, humans make all judgments about the placement of Lectical Items. 

If you'd like to know more about CLAS, please contact us.