79 lines
3.9 KiB
Plaintext
79 lines
3.9 KiB
Plaintext
Source: http://www1.ics.uci.edu/pub/machine-learning-databases/space-shuttle/
|
|
|
|
1. Title: Challenger Space Shuttle O-Ring Data (2 databases)
|
|
|
|
2. Sources:
|
|
-- David Draper (draper@math.ucla.edu)
|
|
University of California, Los Angeles
|
|
-- Donor: David Draper (draper@math.ucla.edu)
|
|
-- Date: 5 August 1993
|
|
|
|
3. Past Usage:
|
|
|
|
1. Draper,~D. (1993). Assessment and propagation of model uncertainty.
|
|
In {\it Proceedings of the Fourth International Workshop on Artificial
|
|
Intelligence and Statistics} (pp. 497--509). Ft. Lauderdale, FL:
|
|
Unpublished.
|
|
-- Discrete model uncertainty analysis
|
|
-- Analysis suggests that obvious different extrapolations of the
|
|
data exist at 31 degrees Fahrenheit (i.e., freezing), which sharply
|
|
discredits the assumption of no temperature effect.
|
|
2. Dalal,~S.~R., Fowlkes,~E.~B., \& Hoadley,~B. (1989). Risk analysis of
|
|
the space shuttle: pre-Challenger prediction of failure. {\it Journal
|
|
of the American Statisticians Association}, {\it 84}, 945--957.
|
|
3. Lavine,~M. (1991). Problems in extrapolation illustrated with space
|
|
shuttle O-ring data. {\it Journal of the American Statisticians
|
|
Association}, {\it 86}, 919--922.
|
|
4. Martz~H.~F., \& Zimmer,~W.~J. (1992). The risk of catastrophic failure
|
|
of the solid rocket boosters on the space shuttle. {\it American
|
|
Statistics}, {\it 46}, 42--47.
|
|
|
|
4. Number of instances: 23 in each of two files
|
|
|
|
5. Relevant Information:
|
|
|
|
There are two databases: (both use the same set of 5 attributes)
|
|
1. Primary o-ring erosion and/or blowby
|
|
2. Primary o-ring erosion only
|
|
The two databases are identical except for the 2nd attribute of the
|
|
21st instance (confirmed by David Draper on 8/5/93).
|
|
|
|
Edited from (Draper, 1993):
|
|
The motivation for collecting this database was the explosion of the
|
|
USA Space Shuttle Challenger on 28 January, 1986. An investigation
|
|
ensued into the reliability of the shuttle's propulsion system. The
|
|
explosion was eventually traced to the failure of one of the three field
|
|
joints on one of the two solid booster rockets. Each of these six field
|
|
joints includes two O-rings, designated as primary and secondary, which
|
|
fail when phenomena called erosion and blowby both occur.
|
|
The night before the launch a decision had to be made regarding
|
|
launch safety. The discussion among engineers and managers leading to
|
|
this decision included concern that the probability of failure of the
|
|
O-rings depended on the temperature t at launch, which was forecase to
|
|
be 31 degrees F. There are strong engineering reasons based on the
|
|
composition of O-rings to support the judgment that failure
|
|
probability may rise monotonically as temperature drops. One other
|
|
variable, the pressure s at which safety testing for field join leaks
|
|
was performed, was available, but its relevance to the failure process
|
|
was unclear.
|
|
Draper's paper includes a menacing figure graphing the number of field
|
|
joints experiencing stress vs. liftoff temperature for the 23 shuttle
|
|
flights previous to the Challenger disaster. No previous liftoff
|
|
temperature was under 53 degrees F. Although tremendous extrapolation
|
|
must be done from the given data to assess risk at 31 degrees F, it
|
|
is obvious even to the layman "to foresee the unacceptably high risk
|
|
created by launching at 31 degrees F." For more information, see
|
|
Draper (1993) or the other previous analyses.
|
|
The task is to predict the number of O-rings that will experience
|
|
thermal distress for a given flight when the launch temperature is
|
|
below freezing.
|
|
|
|
6. Number of Attributes: 5
|
|
1. Number of O-rings at risk on a given flight
|
|
2. Number experiencing thermal distress
|
|
3. Launch temperature (degrees F)
|
|
4. Leak-check pressure (psi)
|
|
5. Temporal order of flight
|
|
|
|
7. Attribute Information: all values are positive integers
|