EVIDENCE FOR NON-RANDOMNESS OF 'FOUR-STATE ELECTRONIC RANDOM STIMULUS GENERATOR'
Document Type:
Collection:
Document Number (FOIA) /ESDN (CREST):
CIA-RDP96-00787R000200150005-1
Release Decision:
RIPPUB
Original Classification:
C
Document Page Count:
4
Document Creation Date:
November 4, 2016
Document Release Date:
March 23, 2000
Sequence Number:
5
Case Number:
Publication Date:
June 12, 1975
Content Type:
MF
File:
Attachment | Size |
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CIA-RDP96-00787R000200150005-1.pdf | 277.6 KB |
Body:
Approved ForRelease2000/0.811.0 ? CIA-RIPP96-00787R000200150005-1
L'UN I IDLN IAL
ORD 224D-75
12 June 1975
MEMORANDUM FOR: OTS/CB
SG1 I
ATTENTION:
SUBJECT: Evidence for Non-Randomness of "Pour-State
Electronic Random Stimulus Generator"
REFERENCE: OTS/CB Memorandum 075-60
As requested in the last paragraph of the referenced
memorandum, we have investigated the data provided to establish
evidence for randomness. The basis for suggesting non-randomness
Is as follows:
Table 1 of the Reference provides data concerning fre-
quencies of:
A. Initial States
B. State Transitions
Since the experiment consisted of requiring the subjects
to indicate the next-to-be presented state, it would seem most
important to establish that all possible transitions occur
with equal probability. To test for possible non-equality
of transitions, we extracted the observed frequencies of non-
identity transitions to form the following table:
Yellow
Green
Blue
Red
764
765
790
G
777
773
863
B
776
796
773
R
787
852
803
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This table can be restructured as a tw by-six table
asfollows:
YIG Y/B Y/R GIB
Forward 764
765
790
773
863
773
Backward 777
776
787
796
852
803
The table thus restructured brings together all possible
non-identity transitions viewed as state-pairs. For instance,
Col. I shows that there were 764 transitions from the yellow
state to the green state and there were 777 transitions from
the green state to the yellow state. Under the hypothesis that
all state transitions are equally probable and equally affected
by thence the observed frequency with which forward transitions
*CC= Should be unrelated to that with which backward transitions
occur in the same pair. This condition is not met. There is
a very strong relationship between the observed forward and back-
ward transition frequencies. The coefficient of correlation
between frequencies for these two directions, computed across
all six possible non-identity transitions is .93, (p< .01)
(see attached graph). This finding shows that there were, in
fact, systematic pair-wise biases associated with the electronic
processes by which the transitions were selected.
The finding that the forward and backward transitions are
closely associated with respect to joint probability of occurrence
suggests that they can be considered as having been drawn from
the same population. To test this, we computed the forward and
backward mean and the Standard Deviation (SD) of the observed
frequencies. They are:
Forward 788 37.9
Backward 798 28.25
The standard error of the difference between these two means is
15.39 while the difference between them is only ten; clearly
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these data
table:
Observed
may be merged.
Y/G Y/B
Merging them provides
the
C
ng
Bf Total
Frequency
1541
1541
1577
i69
1715
15769519
Expected
Frequency
Under Null
Hypothesis
1586.5
1586.5
1586.5
1586.5
1586.5
951
Chi Square
1.305
.057
93
10.408
.069
Total Chi Square 0. 13.337 4f5 p.UZ
In the above table it can be seen that the large excess of
ob ?Dyed transitions involving the red-green pair is significant
at the .02 level. Inspection of the observed frequencies reveals
that there are almost ten percent more transitions involving the
red-green pair than the average of the other five possible non-
identity transitions.
These results suggest that adopting (for whatever conscious
or unconscious reason) a strategy of "When green, press red,
when red, press green and, otherwise use the 'pass' button as
much as possible" will increase one's hit score. Using an
instrument with the above-described characteristics and
strategies such as this is certain to produce "statistically
significant" results, given enough trials and the assumption
of random transition probabilities. Other biases also exist
which could form the bases of other enhancing strategies but
the above discussion would seer adequate to establish the
existence of non-randomness which we have suggested.
The report available to us contains data only upon one test
of one instrument. it must, therefore, be assumed that the other
instruments demonstrated non-random characteristics of a similar
nature. Further, the report does not reveal which subject used
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which instrument so we are unable to ascertain whether or not
subject number 2's results could be due to the effects discussed
aboye1 but the magnitude of the effect is adequate to explain
the results if one assumes the adoption of a selection strategy
which "capitalizes" upon the non-random characteristics which
are demonstrably present
Attachment
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LSR File, Watt
LSR Chrono, Watt
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:may:3191
I!!!!!!!!!!!"
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