Source Hierarchy
How to weight and prioritize different information sources when conducting investment research.
Not all information is equal. Weight sources deliberately based on their proximity to the truth.
First-hand sources (highest weight)
Company disclosures and earnings call transcripts are where you start. These are the words of the people running the business — no filter, no editorial spin. SEC filings, investor presentations, and annual reports fall into this category.
Before reading any commentary or analysis, go to the primary source. Form your own initial impressions before exposing yourself to someone else's interpretation.
Secondary sources
YouTube analyses, newsletters, and Substack writers are useful for discovering ideas and encountering different perspectives. They are inputs to your thinking, not substitutes for your own analysis.
A well-argued bull case from a respected analyst may be compelling, but unless you have done the work to understand the business yourself, you are borrowing conviction. Borrowed conviction breaks down at the first sign of trouble.
Tertiary sources
Industry books provide deep domain understanding. A good book gives a coherent picture of an entire domain — its economics, competitive dynamics, and historical context. Founder and CEO books (biographies, memoirs) build understanding that makes everything else easier to interpret.
Books operate on a different timescale than earnings calls or newsletters. They are not useful for making a decision this week, but they compound in value over years by shaping how you think about entire industries.
Applying the hierarchy
When sources conflict, defer to the higher-weight source. If a newsletter claims a company is struggling but the earnings call transcript tells a different story, go with what management actually said — then verify their claims over time.
Related
- Earnings Call Analysis — the most important first-hand source in practice
- Trust and Verify — how to calibrate the reliability of what management tells you
- AI Research Tools — using AI to process and contextualize sources faster