Raw scores of zero are not uncommon on high-range mental ability tests. This report contains some objective statistics thereon, and provides insight into the apparent causes leading candidates to score zero; that is, to fail to give even one single correct answer.
| Test | # zero scores |
|---|---|
| Isis Test | 40 |
| Daedalus Test | 10 |
| The Nemesis Test | 8 |
| The Test To End All Tests | 5 |
| Test For Genius — Spatial section (Revision 2004) | 4 |
| Test For Genius — Verbal section (Revision 2004) | 3 |
| A Paranoicac's Torture: Intelligence Test Utilizing Diabolic Exactitude | 2 |
| Test For Genius — Numerical section (Revision 2010) | 2 |
| The Marathon Test — Spatial section | 2 |
| Short Test For Genius | 2 |
| A-10 — Early experimental association test | 2 |
| Test For Genius — Revision 2004 | 2 |
| Cooijmans Intelligence Test — Form 2 | 2 |
| A-21 — Early experimental association test | 2 |
| Cooijmans Intelligence Test — Form 3 | 1 |
| The Final Test | 1 |
| The Marathon Test — Verbal section | 1 |
| The Marathon Test — Numerical section | 1 |
| Test For Genius — Numerical and spatial sections (Revision 2010) | 1 |
| The Marathon Test | 1 |
| Test For Genius — Revision 2010 | 1 |
| The Marathon Test — Numerical and spatial sections | 1 |
| Spatial Insight Test | 1 |
| Association and Analogies — German version | 1 |
| Analogies of Long Test For Genius | 1 |
| Analogies #1 | 1 |
| Reason | 1 |
| A-15 — Early experimental association test | 1 |
| A-16 — Early experimental association test | 1 |
| A-17 — Early experimental association test | 1 |
Note: Not included here are scores of zero on tests where a score of zero does not imply zero correct answers; for instance, on the Qoymans Multiple-Choice #5, zero correct answers lead to a score of -100 rather than zero.
The top two or three tests in this table (Isis, Daedalus, and Nemesis) are so difficult that it is normal and to be expected that many or most candidates score zero. The first two of these tests will not be considered further in this report. The remaining tests, however, have more moderate levels of difficulty, so that scores of zero are not self-obvious and it is worthwhile to study them closer. The Nemesis Test is really a borderline case, but will be included.
Below are the apparent causes of these candidates' failure to give even one correct answer, as observed and assessed by the scorer; the most frequent cause is here called "lack of ability", meaning that the test was simply too hard for the candidate. Were the Isis and Daedalus tests included here, their scores of zero would all or almost all fall under "lack of ability".
| Apparent cause | # scores |
|---|---|
| Lack of ability | *************************** |
| Psychosis at the time of test-taking | ************ |
| Lack of ability combined with disorderliness | *** |
| Laxity and laziness | ** |
| Cultural disadvantage | ** |
| Lack of ability combined with a paranoid-megalomanic inclination | * |
| Submitting more or less random answers to verify a hypothesis about the test or scoring method | * |
| Being confused and high-flown but short of full-blown psychosis | * |
| Lack of ability combined with physical handicap | * |
| Sex | # scores |
|---|---|
| Male | ******************************** |
| Female | ************ |
| Intersexual |
Considering the male/female ratio among high-range test candidates, which is about 11 based on the latest information, females are overrepresented among candidates who score zero.
| Educational level | # scores |
|---|---|
| A few years primary school | **** |
| A few years secondary school | ** |
| Secondary school completed | ******************* |
| Bachelor | ***** |
| Master | ****** |
| Doctor | * |
| Unknown | ************* |
| Country | # scores |
|---|---|
| Germany | ************* |
| United States | ******** |
| Netherlands | **** |
| Norway | **** |
| Finland | *** |
| Greece | *** |
| United Kingdom | *** |
| Italy | ** |
| Lithuania | ** |
| Singapore | ** |
| Unknown | ** |
| Ireland | * |
| Japan | * |
| Tunisia | * |
| Turkey | * |
| Age class | # scores |
|---|---|
| 50-54 | ** |
| 45-49 | ** |
| 40-44 | *** |
| 35-39 | *** |
| 30-34 | ******* |
| 25-29 | ************* |
| 22-24 | ****** |
| 20-21 | |
| 18-19 | * |
| 17 | |
| 16 | |
| 15 | |
| 14 | * |
| Unknown | **** |
Note: The number of scores in this table is not the same as that in some of the other tables because the "age when taken" information is stored only at subtest level in case of compound tests.
| Year taken | # scores |
|---|---|
| 1995 | ***** |
| 1996 | *** |
| 1997 | |
| 1998 | |
| 1999 | |
| 2000 | |
| 2001 | * |
| 2002 | * |
| 2003 | * |
| 2004 | ** |
| 2005 | *** |
| 2006 | **** |
| 2007 | **** |
| 2008 | ** |
| 2009 | |
| 2010 | * |
| 2011 | * |
| 2012 | **** |
| 2013 | ********* |
| 2014 | ** |
Note: The number of scores in this table is not the same as that in some of the other tables because the "year taken" information is stored only at subtest level in case of compound tests.
It may be relevant to note that in 1995 and 1996, early tests were sometimes administered in face-to-face or group situations, and several scores of zero occurred then. From 1996 to early 2001 the tests were spread via printed I.Q. society journals, and candidates submitted answers and received score reports via regular mail. In that period, almost no scores of zero occurred. From early 2001 on, the tests have been spread via the Internet, and answers can be submitted via electronic mail. In that period, a more or less steadily growing number of scores of zero has occurred.