Collection and characterization of spelling errors in scientific and scholarly text

The SPEEDCOP (SPEIIing Error Detection correction Project) project recently completed at Chemical Abstracts Service (CAS) extracted over 50,000 misspellings from approximately 25,000,000 words of text from seven scientific and scholarly databases and showed that the expected incidence of misspelling is 0.2%, that 90–95% of spelling errors have only a single mistake, and that substitution is homogeneous while transposition is heterogeneous.