file: oldnstdb.doc G. Moody August 1992
Copyright (C) Massachusetts Institute of Technology 1992. All rights reserved.
This directory contains the first edition of the MIT-BIH Noise Stress Test
Database, reproduced here for the sake of completeness. Unless you wish to
repeat an experiment based on the first edition, use the records in the main
`nstdb' directory of this disk (see `../nstdb/nstdb.doc').
In the main `nstdb' directory, very long-term baseline drift (less than 0.05
Hz) has been removed from records `bw', `em', and `ma'. The original versions
of these records from the first edition of this disk are records `oldbw',
`oldem', and `oldma' in this directory.
The signal-to-noise ratios of the sample noise stress test records in this
directory are not calibrated as stated in the `readme.doc' file on the first
edition of this disk. Using the same definition of SNR as for the records in
the main `nstdb' directory, the SNRs for these records are (in dB):
Record Signal 0 Signal 1 Record Signal 0 Signal 1
118_02 19.79 14.38 119_02 20.31 13.79
118_04 13.77 8.36 119_04 14.29 7.77
118_06 10.25 4.84 119_06 10.76 4.25
118_08 7.75 2.34 119_08 8.27 1.75
118_10 5.81 0.41 (*) 119_10 6.33 -0.19
118_12 4.23 -1.18 119_12 4.74 -1.77
(*) Signal 1 was inadvertently omitted from the version of record 118_10 that
appeared on the first edition of this disk; it has been restored here.