General Report on Tunny

22H Page 70

increase as |Π ... - Πxx| increases (R2 p. 96)    (H11)

(ii)  
But                      (from H6).  
   
   (H12)

The following table gives value for ΔD1 = ΔD2 = dot, L = x etc. for the messages considered in Figs. 22, (VI) (VII) (VIII).

 
ΔD1 ΔD2 L Type
A		 Type
B		 Type
C
.
.
x
x		 .
x
x
.		 x
x
x
x		 490
278
497
283		 404
322
495
327		 406
386
385
371
.
.
x
x		 .
x
x
.		 .
.
.
.		 421
400
439
392		 435
433
400
384		 465
402
406
379
Fig. 22 (XIII)

(g) Δ2D.

Δ2D = Δ2P + Δ2Ψ'

It was several times suggested that methods involving use of Δ2D frequencies should be used. However counts taken showed that although the count of Δ2P was more bulgy than that of ΔP nevertheless the count of Δ2Ψ' was feeble compared with that of ΔΨ'. As the result the count of Δ2D has no statistical (or other) advantages over that of ΔD. (See R3 p. 44-5, 52-3 and R4 p. 131-3 for example of Δ2D counts) (First Δ2D count R1 p. 82).


(h) Bigrams in ΔD.

Little work was done on bigram frequencies. Some experiments, however showed that the frequency of ΔD1 + ΔD2 bigrams .., .x, xx, x. did not differ significantly from the estimated frequency assuming random juxtaposition (R3 p. 63)

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