Errors in Multistep Tasks

Some tasks, such as making database queries, involve multiple steps. Even if the error rate per step is small, the error rate for the whole task may be considerable.
 
Study Detail
Error Rate
Card, Moran, & Newell [1980] Errors using command-line text editor, experienced users. 
30%
Card, Moran, & Newell [1980] Errors using 10 command-line systems, 28 experienced users, 14 tasks. 
33%
Card, Moran, & Newell [1980] Errors using command-line text editor, highly experienced users. 
30%
Card, Moran, & Newell [1983] Experiment 5C, p. 177. 70 tasks. 7 typing errors, correction taking only 4% of total correction time. 3 "Big Errors," correction taking 72% of correction time. 
37%
Chan, Lu, & Wei [1993] Percentage of 136 surveyed professional SQL users who say they usually take more than one try to do a query.
82%
Dhillon [1986] Procedural error in reading list of instructions. Per list.
6.5%
Gould Reisner, 1981. Query specification errors in QBW, 39 high school and college students. Per query.
33%
Gould Reisner, 1981. Query specification errors in QBW, 39 high school and college students. Per query.
33%
Greenblatt & Waxman [1978] Query specification errors, paper and pencil exercise. Per query.
25% - 27%
Ledgard [1980] Percentage of erroneous commands in text editor. 8 experienced users. English-like editor, notational editor. Per command.
5.6% - 9.9%
Reisner [1975] Query specification errors on final exam, SEQUEL, programmers. Per query.
22%
Roberts [1979] Text editor, time spent in error recovery, not percentage of actions. Excludes errors corrected in a few seconds. 8 text editors, 4 experience users apiece. Percentage of command time.
11%
Smelcer [1995] 20 undergraduates with 80 minutes of training in SQL. Only counted errors in which a required join was not used. Percentage of queries with such errors. 6% if low memory load, 12% if medium memory load, 17% with high memory load. Per query.
14%
Swain & Guttman [1983] Using a checklist incorrectly (cascade of tasks, not single task). Per checklist.
50%

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