Computer Or Human Error
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THE ACM1 In 1988, the Soviet Union's Phobos 1 satellite was lost on its way to Mars. Why? According to Science magazine, "not long after the launch, a ground controller omitted a single letter in a series of human error quotes digital commands sent to the spacecraft. And by malignant bad luck, that omission caused the
Human Error In Aviation
code to be mistranslated in such a way as to trigger the test sequence" (the test sequence was stored in ROM, but human error percentage was intended to be used only during checkout of the spacecraft while on the ground) [7]. Phobos went into a tumble from which it never recovered. What a strange report. "Malignant bad luck"? Why bad luck: why https://securityintelligence.com/how-to-reduce-human-error-in-information-security-incidents/ not bad design? Wasn't the problem the design of the command language that allowed such a simple deviant event to have such serious consequences. The effects of electrical noise on signal detectability, identification, and reliability are well known. Designers are expected to use error-detecting and correcting codes. Suppose interference from known sources of electromagnetic noise had corrupted the signal to Phobos. We would not blame the ground controllers: we would say that the http://www.jnd.org/dn.mss/commentary_human_er.html system designers did not follow standard engineering practice, and we would reconsider the design of the system so as to protect against this problem in the future. People err. That is a fact of life. People are not precision machinery designed for accuracy. In fact, we humans are a different kind of device entirely. Creativity, adaptability, and flexibility are our strengths. Continual alertness and precision in action or memory are our weaknesses. We are amazingly error tolerant, even when physically damaged. We are extremely flexible, robust, and creative, superb at finding explanations and meanings from partial and noisy evidence. The same properties that lead to such robustness and creativity also produce errors. The natural tendency to interpret partial information -- although often our prime virtue -- can cause operators to misinterpret system behavior in such a plausible way that the misinterpretation can be difficult to discover. Quite a lot is known about human performance and the way it applies to system interaction [1]. Several classes of human error have been identified and studied and conditions that increase the likelihood of error can be specified in advance [3, 4, 5]. Communication systems can be designed to be error-tolerant and error-detecting or correcting. In a similar way, we could devise a science of error-tolerant, detecting or minimization interactions with human operator
iTunes or Google Play,or view within your browser. More information here Failure and Recovery PDF December 6, 2004Volume 2, issue 8 Coping with Human Error Errors Happen. http://queue.acm.org/detail.cfm?id=1036497 How to Deal. Aaron B. Brown, IBM Research Human operator error is one of the most insidious sources of failure and data loss in today's IT environments. In early 2001, Microsoft suffered a nearly http://www.sciencedirect.com/science/article/pii/S000368700600041X 24-hour outage in its Web properties as a result of a human error made while configuring a name resolution system. Later that year, an hour of trading on the Nasdaq stock exchange was human error disrupted because of a technician's mistake while testing a development system. More recently, human error has been blamed for outages in instant messaging networks, for security and privacy breaches, and for banking system failures. Although these scenarios are not as spectacularly catastrophic as their analogues in other engineering disciplines--the meltdown of the Chernobyl nuclear plant or the grounding of the Exxon Valdez oil tanker, for example--their societal consequences computer or human can be nearly as severe, causing financial uncertainty, disruption to communication, and corporate instability. It is therefore critical that the designers, architects, implementers, and operators of today's IT infrastructures be aware of the human error problem and build in mechanisms for tolerating and coping with the errors that will inevitably occur. This article discusses some of the options available for embedding "coping skills" into an IT system. THE INEVITABILITY OF HUMAN ERROR Human error happens for many reasons, but in the end it almost always comes down to a mismatch between a human operator's mental model of the IT environment and the environment's actual state. Sometimes this confusion arises from poorly designed status feedback mechanisms, such as the perplexing error messages that Paul Maglio and Eser Kandogan discuss elsewhere in this issue (see "Error Messages: What's the Problem?" on page 50), but other times the mismatch simply arises from a lack of experience on the operator's part, or worse, to quirks of human cognitive processing that can obstinately steer even an experienced operator toward the wrong conclusion.1 Regardless of the source, however, psychology tells us that mental-model mismatches, and thus human error, are inevitable in the rapidly changing environments characte