# SignedSlabIndex

> Prices for certified autographs, organised by who signed them, what
> was signed, who certified it and what grade it carries.

Only items certified by PSA/DNA, JSA, Beckett, SGC or CGC appear here.
A seller's own certificate of authenticity is a different claim and this
index does not carry it.

A signed item is usually one of one, so there is nothing to compare it
against directly. Comparisons are made one level up, against other items
by the same signer of the same type and certification. The pages say
when that is what they are doing.

## Understanding the numbers
- [Methodology](https://signedslabindex.com/methodology/): what is counted, what is not, and why an accepted best offer is shown as a ceiling

## Browsing
- [Every signer tracked](https://signedslabindex.com/signers/)
- [Browse](https://signedslabindex.com/browse/)
- [Price drops](https://signedslabindex.com/drops/)
- [Listings worth reviewing](https://signedslabindex.com/deals/): priced below others of the same kind

## Writing
- [Articles](https://signedslabindex.com/articles/): pieces on what certification actually claims, what the market pays, and where the two diverge

## What this index cannot see

- eBay returns at most 1,000 results for any search, however deep the
  paging goes, so a signer with a very large market may have listings
  this index never reaches.
- A fixed-price listing has no end date, so this index learns one has
  gone by ceasing to find it rather than by watching it close. Where a
  listing has not been seen for two days the page marks it.
- eBay never publishes what an accepted best offer actually paid, so
  those sales are shown as a ceiling rather than as a price.
- A certificate is an expert opinion rather than a finding of fact.
  This index reports what a recognised company certified and does not
  judge whether a signature is genuine.