What this byline covers
The screening section: what a filter removes, how the three statements connect, how the Piotroski and Altman frameworks are computed, and where each one stops applying. The F-Score worksheet and Z-Score calculator sit here.
How published frameworks are treated
Where a page describes a published framework, the original definition governs. Coefficients and thresholds are quoted as published, and any adjustment is called a variant rather than presented as the framework itself. Both papers are careful about their own scope, and that care is reproduced rather than smoothed away.
What this byline does not claim
No score is presented as a verdict and no company is named as a pass or a fail. Worked examples use constructed figures, because the purpose is that a reader can run the same calculation over any filing and know what each term is doing.
Where the pages spend their length
On definitions, disproportionately. Most screening mistakes are not arithmetic errors but definitional ones: a column labeled P/E that resolved four questions silently, a market capitalization computed one way for a share and another for a token, a field that dropped every row where the data was missing. These pages therefore spend as long on what a term means as on what to do with it.
On scores and their scope
Both frameworks covered here were designed to answer narrow questions, and both original papers are explicit about their limits. Reproducing that care matters more than presenting a clean number: a score computed correctly on a company the criteria were never fitted for is arithmetically right and economically meaningless, and saying so is part of explaining it.
The vocabulary of a filter
Four distinctions do most of the damage when a screen returns something unexpected, so the pages here name them every time. Trailing twelve months and the last fiscal year are different periods, and a screener that mixes them across two columns is comparing nothing. Diluted and basic share counts give different per-share figures from the same profit. A restated figure and the figure as originally filed will both be described as the number for that year, and only one of them matches the filing a reader has open. And a missing value is not a zero. A filter that quietly treats it as one will rank a company that reported nothing above a company that reported badly.
Why a worksheet rather than a verdict
The two calculators here ask the reader to enter the inputs rather than fetching them from a data feed, and that is deliberate. Nine tests entered by hand force each line item to be found in an actual filing, which is where the definitional work happens and where a wrong column is caught. A tool that returns a score from a ticker teaches nothing about which figure produced it, and it hides the one thing worth knowing: that the same company scores differently depending on which period and which share count were used. The arithmetic is the easy half.
This byline and the other
The screening pages carry this byline; the options, broker and execution pages carry the other one. What a standing byline means here, and why the site publishes under them instead of anonymously, is set out on the about page. Corrections to any page under it are welcome and are made on the page rather than quietly: the contact page explains the most useful form for them, and the editorial policy sets out the standard every claim is held to.
About this byline
Who is answerable for the screening pages?
This byline, for the section as a whole rather than for individual articles: the filters, the three statements, the published scores and the bond arithmetic alike. Why the site publishes this way is set out on the about page.
Are the worked examples real companies?
No. The figures in every worked example are constructed and chosen so the arithmetic is legible: a strike of 50, a premium of 3, a ratio that comes out round. No page names a company as a pass or a fail, because the point is that you can run the same calculation over any filing you like.
Why do these pages spend so long on field definitions?
Because a screener column labeled P/E has already resolved at least four questions for you: which earnings figure, over which twelve months, adjusted or as-reported, and what to do when the number is negative. Two vendors resolve those differently and label the column identically, so the definition is where a surprising screen result is explained.
Do the published scores here predict returns?
No, and the original papers are careful about that too. The F-Score asks whether nine specific fundamentals improved; the Z-Score estimates distance from financial distress. Neither was designed to pick winners, and using them that way is a category error rather than a subtle misuse.
I get a different number working through an example — what should I check first?
The input definition, before the arithmetic. Most disagreements on a score come from which figure was taken for a term, whether trailing or forward, adjusted or as-reported, or which of two similarly named balance-sheet lines, rather than from a mistake in the formula. Each worked example names the line it used for exactly that reason; if one is genuinely wrong, the contact page is the place to say so.