Proofreading
catches about 90% of all nonword spelling errors and about 70% of all word
spelling errors. The table below shows that error detection varies widely by
the type of task being done.
In general, our error detection rate only
approaches 90% for simple mechanical errors, such as mistyping a number.
For logic errors, error detection is far
worse, often 50% or less.
For omission errors, where we have left
something out, correction rates are very low.
|
Source |
Event |
Initial Error Rate |
Detection Rate |
Residual Error Rate |
|
Allwood [1984] |
Students solving statistics problems. |
|
64% |
|
|
All Errors |
|
|
64% |
|
|
Simple Mechanical
Errors |
|
|
83% |
|
|
Simpler Logic
Errors |
|
|
48% |
|
|
Complex Logic
Errors |
|
|
25% |
|
|
Omission Errors |
|
|
0% |
|
|
Baddeley & Longman [1973] |
Postal workers typing mail codes. |
1% |
50% |
0.5% |
|
Barnara et al. [1987] |
8 experienced operators of hot strip steel
mill, simulated production planning exercise. 95 errors, detected 74. |
|
78% |
|
|
Basili, Daskalantonakis, & Yacobelis
[1994] |
System functional specifications |
|
72%-85% |
|
|
Basili, Daskalantonakis, & Yacobelis
[1994] |
Software Functional Specification |
|
67%-80% |
|
|
Basili, Daskalantonakis, & Yacobelis
[1994] |
Detailed Design |
|
49%-81% |
|
|
Basili, Daskalantonakis, & Yacobelis
[1994] |
Code Inspection |
|
25%-44% |
|
|
Boehm and Basili (2001) |
Many code inspections. Range / Median. |
|
31%-93% |
|
|
60% |
||||
|
Cohen, A. [1980] |
Shadowed (repeated) spoken speech; against
instructions, corrected phonological errors |
|
60% |
|
|
Cohen, A. [1980] |
Shadowed (repeated) spoken speech; against
instructions, corrected word transposition errors |
|
15% |
|
|
Cohen, G. [1980] |
Shown all but last word in a sentence.
Then shown last word. Asked it it is correct. Endings really correct. Percent
declared to be correct. |
|
90% |
|
|
Eick et al. [1992] |
Team inspection of 13 documents with
teams. |
|
80% |
|
|
Eick et al. [1992] |
Team inspection. Inspection of document
with team of 8. Found 18 faults alone before meeting (12 only by 1 person), another
6 in meeting. Mathematically, probably missed another 4. So missed 4/28. |
|
85.7% |
|
|
Fagan [1976] |
Percentage of programming errors found in
team code inspection. 3.8% of lines found with errors in inspection. Errors found
in another 0.8% after delivery. |
|
82% |
|
|
Hall, A. [1996] |
Errors per LOC. Total, discovered after
delivery. |
1.1% |
68% |
0.75% |
|
Hotopf [1980] |
Daily life sample speech errors, S ample
(oral speech errors) |
|
71%-83% |
|
|
Hotopf [1980] |
Written grammatical errors, written
undergraduate sample, per word |
|
17%-65% |
|
|
Johnson & Tjahjono, [1997] |
Code inspection of program with seeded
errors, errors found by individuals working alone. Best subject found 38%. |
|
23% |
|
|
Johnson & Tjahjono, [1997] |
Code inspection of program with seeded
errors, errors found by interacting teams of 3. Best group found 63% |
|
44% |
|
|
Johnson & Tjahjono, [1997] |
Code inspection of program with seeded errors,
errors found by nominal groups of 3 drawn from individuals working alone |
|
43% |
|
|
Jones [1986] |
Team inspection. Errors found in formal
technical review; summary from knowledge of several studies |
|
75% |
|
|
Jones [1998] |
Defect removal rate suggested by Jones |
|
|
|
|
Each software test (p. 198) |
30% |
|||
|
Each formal design inspections (p. 199) |
65% |
|||
|
Each formal code inspection (p. 199) |
60% |
|||
|
Kolkhorst & Macina [1988] |
Space shuttle. Percentage of errors caught
in design and code inspections, compared to total errors found before
release. Initially / late in project. |
|
~50% |
|
|
85% |
||||
|
Lackner [1980] |
Shadowed (repeated) spoken speech; against
instructions, corrected grammatical errors |
|
28% |
|
|
Lackner [1980] |
Shadowed (repeated) spoken speech; against
instructions, corrected semantic errors |
|
14% |
|
|
McCormick [1983] |
Code inspection of AT&T system. 1/10
delivered errors of previous releases (6% of all LOC in previous). Total /
Found after delivery. |
4.4% |
86% |
0.6% |
|
Noteboom [1980] |
Meringer's corpus of linguistic slips,
phonological corrections |
|
75% |
|
|
Noteboom [1980] |
Meringer's corpus of linguistic slips,
lexical corrections |
|
57% |
|
|
Rabbit [1990] |
Flash one of two letters on display
screen. Subject hits one of two keys in response. Allowed to correct. |
5.8% |
90% |
0.6% |
|
Rabbit [1990] |
Flash one of two letters on display
screen. Subject hits 1 of 1 keys in response. Cannot correct but signals
error by hitting button. Corrected more errors than recognized: error
correction partially automatic, unconscious. Percent of errors signaled. |
|
64% |
|
|
Rizzo, et al. [1986] |
16 naïve subjects trained
to use a database system. Trainined in tocking aloud methodology. 4
experimental sessions each. No time limits. 924 errors. Corrected 780. |
|
84% |
|
|
80% |
||||
|
Ruby, Dana & Biche [1975] |
Errors during coding versus errors at
validation stage (late). Faults per line of code. |
10% |
87% |
2% |
|
Schoonard & Boies [1975] |
Line-oriented text editor. Error rate per
word. 3.4% without correction, 0.52% with error correction. |
3.92% |
67% |
0.52% |
|
Wing & Baddeley [1980] |
Grammatical errors per
word, Cambridge examination, per word |
1.24% |
56% |
0.54% |
|
38% |
||||
|
Woods [1984] |
23 nuclear plant crews in simulations. 8
failure events each. Detected errors overall. |
|
~2/3 |
|
|
Woods [1984] |
24 nuclear plant crews in simulations. 8
failure events each. Detected execution errors (slips and lapses) overall. |
|
~Half |
|
|
Woods [1984] |
25 nuclear plant crews in simulations. 8
failure events each. Detected errors involving a misdiagnosis of the
situation, overall. |
|
0% |
|