For Printed Materials: The Probability of Appearance
- by Bruce E. McKinney

An obtainable early imprint
Print runs/Number of pages | 1 to 16 Pages | 17 to 71 Pages | 72 + Pages |
400 or less Copies | 6 | 11 | 0 |
401 to 1000 | 6 | 15 | 4 |
1,001 to 4,000 | 3 | 4 | 3 |
4000+ | 1 | 1 | 1 |
Let's look at statistics comparing the number of pages to the number of copies located in the OCLC. For works of at least 72 pages the survival rate in the OCLC is 1 in 184. Thus if a 1,000 copies were printed and the item had at least 72 pages we can estimate there will be 5 or 6 copies in the OCLC. For material, mostly pamphlets, with 17 to 71 pages the survival rate is 1 in 221, for pamphlets of 16 pages or less 1 in 502. When few copies were printed and the item had 16 pages or less the likelihood of survival is very small. When the print run as well as the number of pages is small we see mass extinction.
Publications & Copies | 1 to 16 Pages | 17 to 71 Pages | 72 + Pages | |||
present | not present | present | not present | present | not present | |
400 or less Copies | 33% | 67% | 36% | 64% | ||
401 to 1000 | 28% | 72% | 63% | 37% | 80% | 20% |
1,001 to 4,000 | 100% | 0% | 100% | 0% | 100% | 0% |
4000+ | 0% | 100% | 0% | 100% |
Both small print run and small page count are strong nagatives for survival. Such material is automatically uncommon although not necessarily important or valuable. Most examples are simply curiosities.