Base Decision Value (BDV)
Measuring cognitive demand at the level of decisions — not at the level of questions.
Base Decision Value (BDV): Measuring Cognitive Demand
In education, “difficulty” is often treated as a property of a question. A question is labelled easy or hard. A topic is placed at a lower or higher level. A learner is judged based on whether they succeed.
But educators know this is an oversimplification. Two questions at the same level can place very different cognitive demands on a student. A short question can be harder than a long one. A familiar-looking problem can require deeper thinking than a complex-looking one.
Phlow Academy separates difficulty from cognitive demand. Base Decision Value (BDV) exists to make that distinction explicit.
How Exams Already Do This Well
Formal examinations already recognise that not all thinking is equal. A five-mark question is usually assessed as all-or-nothing. The student either demonstrates the required understanding or they do not.
A forty- or sixty-mark question is assessed very differently. It is broken into multiple marking points. Credit is awarded for correct method, sound reasoning, partial completion, or intermediate understanding — even when the final answer is incorrect.
Examiners do not ask, “Did the student get this question right?” They ask which parts were understood, where reasoning broke down, and how much thinking was demonstrated.
Base Decision Value applies this same logic before assessment happens — at the level of learning itself.
What Is Base Decision Value?
Base Decision Value represents the inherent cognitive demand of a single decision, for an average learner, independent of context.
It is not a level, a difficulty label, a step count, or a judgement about the student. Instead, BDV describes the kind of thinking a decision requires.
For example, recognising a number, comparing quantities, choosing an operation, interpreting a symbol, or classifying a relationship. Educators instinctively know these are not equally demanding — even when they appear in similar-looking questions. BDV simply formalises that intuition.
“Which Is Harder?” — Teacher Intuition Made Explicit
Ask a teacher: “Which is harder for most students: recognising a number, or choosing the correct operation?” They do not need data to answer. They already know.
Ask: “Which is more demanding: copying a value, or interpreting what a symbol represents?” Again, the answer is immediate.
Teachers constantly make these judgements when allocating marks, giving partial credit, diagnosing misconceptions, and deciding when a student is ready to move on. BDV captures this shared professional intuition so that a learning system can reason in the same way.
Decision Types and Cognitive Demand
Different decision types carry different inherent demands. A decision that requires recognition places a lighter load on working memory than one that requires comparison. A decision that requires choosing an operation demands more cognitive control than one that involves following a known procedure.
Crucially, this remains true regardless of the level the decision appears at, the length of the question, or the student answering it. A Level 1 algebra symbol decision can be more cognitively demanding than a Level 3 counting decision. BDV allows Phlow to recognise that reality.
Inherent Demand vs Personal Effort
BDV describes the baseline demand of a decision. Personal effort is something else entirely.
Two students can face the same decision: for one it confirms fluency, for the other it represents genuine struggle and growth.
BDV does not judge the learner. It defines the starting point. The Personal Learning Journey then adapts based on how that learner responds over time — recognising effort, improvement, and stability. This separation is critical. It allows Phlow to reward learning without assuming anything about the learner.
Why BDV Is Identity-Agnostic by Design
Because BDV applies to decisions rather than people, it does not rely on demographic information. The system does not need to know age, gender, background, or location.
It only needs to know what type of decision was made, how demanding that decision usually is, and how the learner responded.
This avoids conflating learning with identity and keeps the focus on behaviour, understanding, and growth. BDV enables fair comparison across learners without ever categorising learners themselves.
From Marks to Meaningful Analytics
In exams, marks allow educators to distinguish partial understanding from complete misunderstanding, recognise correct reasoning even when execution fails, and judge readiness based on patterns rather than single outcomes.
BDV allows learning analytics to do the same. Rather than treating all correct answers as equal, Phlow can distinguish easy wins from meaningful achievements, fragile success from stable understanding, and progress driven by effort rather than chance.
This leads to analytics that are not just precise, but educationally meaningful.
Why BDV Enables Fairer Progression
When progression is based purely on correctness or completion, learners are treated unfairly: strong learners are over-rewarded for easy work, developing learners are under-credited for real effort, and complex tasks distort pacing.
BDV corrects this. Progress becomes proportional to demonstrated understanding, not to surface difficulty or volume of work.
This mirrors how experienced educators already judge readiness — by looking at what kind of thinking a student can reliably perform.
BDV as a Foundation, Not a Feature
Base Decision Value is not a visible score and not a headline metric. It is a foundation.
It underpins readiness to move on, decision-based rolling windows, learner profiles, personalised pacing, and meaningful dashboards.
Without BDV, learning analytics collapse back into right and wrong. With BDV, learning becomes legible.
Making Cognitive Demand Visible
Education has always relied on professional judgement to assess thinking. Phlow Academy does not replace that judgement — it encodes it.
By treating cognitive demand as something that can be reasoned about explicitly, Base Decision Value allows learning analytics to reflect how understanding is actually assessed in classrooms and exams.
Not by counting answers, but by recognising thinking.