Example Project File #3

Analysis File (Fact–Inference Separation)


File Name: 03_Facts_vs_Inference.md

File Authority

This is an analysis file.
It does not introduce objectives, constraints, or assumptions.

It records:

Facts and inference must remain separated.
Speculation must be labeled.


Purpose of This File

This file exists to prevent factual accuracy from being confused with reasoning quality. Facts alone do not make decisions, and reasoning without facts is ungrounded. This file makes the boundary explicit so conclusions can be evaluated rather than trusted.


Section 1: Verified Facts

(Facts are statements that can be independently verified from reliable sources.)


Fact F1: Average New Vehicle Price (U.S.)

Statement:
The average transaction price for a new vehicle in the U.S. is approximately $47,000–$48,000.

Source Type:
Industry sales and pricing reports (e.g., automotive market analysts).

Status:
Verified (current within last 12 months).


Fact F2: Typical Used Vehicle Price (3–5 Years Old)

Statement:
Used vehicles aged 3–5 years commonly sell in the $20,000–$30,000 range, depending on model and condition.

Source Type:
Used vehicle market data and dealer listings.

Status:
Verified (range-based).


Fact F3: Reliability Variation by Model

Statement:
Vehicle reliability varies significantly by model and production year, even within the same manufacturer.

Source Type:
Aggregated reliability studies and long-term ownership surveys.

Status:
Verified.


Fact F4: Warranty Coverage

Statement:
New vehicles typically include a manufacturer warranty covering major components for 3–5 years, while most used vehicles do not unless sold as certified used.

Source Type:
Manufacturer warranty documentation.

Status:
Verified.


Fact F5: Maintenance Cost Drivers

Statement:
Maintenance and repair costs are influenced by vehicle age, mileage, model complexity, and service history—not age alone.

Source Type:
Automotive maintenance cost analyses.

Status:
Verified.


Section 2: Explicit Inferences

(Inferences are conclusions drawn from facts using reasoning. They are not facts.)


Inference I1

Derived From:
Facts F1 and F2.

Inference:
Purchasing a used vehicle instead of a new one is likely to reduce upfront cost substantially within the defined budget constraints.

Confidence:
Medium–High.

Notes:
Applies broadly but does not account for individual model pricing anomalies.


Inference I2

Derived From:
Facts F3 and F5.

Inference:
Reliability should be evaluated at the model-and-year level rather than inferred from vehicle age or brand alone.

Confidence:
High.

Notes:
Supports rejecting blanket “new is better” assumptions.


Inference I3

Derived From:
Fact F4.

Inference:
New vehicles reduce short-term repair risk through warranty coverage but do not eliminate long-term reliability uncertainty.

Confidence:
Medium.

Notes:
Warranty shifts risk timing, not total risk.


Inference I4

Derived From:
Facts F2, F4, and F5.

Inference:
A certified used vehicle may offer a middle ground between lower purchase cost and reduced near-term repair risk.

Confidence:
Medium.

Notes:
Dependent on availability and certification quality.


Section 3: Labeled Speculation

(Speculation is forward-looking or probabilistic judgment not directly supported by current facts.)


Speculation S1

Statement:
Certain models are likely to maintain reliability over a five-year ownership horizon.

Reason for Speculation:
Long-term reliability projections depend on future usage, maintenance quality, and unknown defects.

Status:
Speculative; must not be treated as fact.


Speculation S2

Statement:
Resale value after five years may partially offset higher upfront costs.

Reason for Speculation:
Future market conditions and buyer demand are unpredictable.

Status:
Speculative; excluded from optimization per constraints.


Section 4: Boundary Check

If a conclusion relies primarily on speculation, confidence must be low.


Closing Note

Facts anchor reality.
Inference creates meaning.
Speculation must remain visible.

This file exists to ensure those roles are never confused.