No, it is not true. Dr. Thomas has explained in great detail why it is false. I quoted Dr. Thomas's entire rebuttal to the NRC panel's 78% figure, but you snipped and ignored the rebuttal, and then treated us to more of your diversionary observations and errant speculation.
You pull this stunt all the time: You ignore arguments that you can't explain; you type several paragraphs of irrelevant observations and flawed speculation; and then you pretend that you have dealt with the arguments.
I am not going to deal with Dr. Thomas who has no support from acoustic experts, not even from his closest allies, for his principle argument, the 1-in-100,000 claim.
One, your explanation is patently absurd. Two, I have not ignored your explanation but have responded to it several times, noting that, among other things, it simply ignores the details of the sonar analysis and the fact that the sonar analysis was able to simulate closer microphones and 180 positions.
"But, but, but . . . they didn't check this microphone or that microphone," etc., etc. Why don't you deal with what they did do in the sonar analysis? Why don't you deal with Dr. Thomas's point-by-point refutation of the NRC panel's bogus value assumptions for their 78% probability of chance?
Not checking for other possibilities is a big deal.
What if, in addition to for correlations of 145.15 with a test shot from the grassy knoll, at Target 3, they also checked the test shot from the TSBD at Target 3.
What if Weiss and Aschkenasy found a strong correlation with a test shot from both the TSBD and the grassy knoll? Just as BBN did with their study.
What if Weiss and Aschkenasy found strong correlations with test shots fired at different targets? Like strong correlations for both Targets 1 and 3, with the same 1963 impulse. Just as BBN did with their study.
What if Weiss and Aschkenasy found strong correlations from two different locations, like within 5 feet of microphone 3 ( 4 ), and within 7 feet of microphone 3 ( 8 ). A strong correlation with the 145.15 impulse with two different microphone locations 40 feet apart. Just as BBN did with their study. We would conclude that these estimates of getting ‘false alarms’ or ‘false positives’ as being on 5%, or 1-in-100,000, are clearly false.
But Weiss and Aschkenasy did not check for these correlations. They did not have enough time. They were using computers to check for correlations, but they did not have enough time. I am skeptical of this. I think they were afraid of having their own data discredit the conclusions they wanted to come to. But just testing one 1963 impulse, with just one 1978 test shot, they insured that this could not happen.
What??? You still have not read the BBN report, have you?
In point of fact, the BBN scientists were tremendously impressed with the locational correlations between the dictabelt gunshots and the test-firing gunshots. They determined that the probability that chance caused those correlations was “less than 1%.” Figure 22 in the BBN report shows the microphone positions along the motorcycle route where high correlations were obtained. The BBN scientists referred to this figure in explaining why there was less than a 1% probability that chance caused the time-distance correlations. I quote from the BBN report, which you really should read some day:
Yes. I have read this. But no statement about checking for all 3,024 combinations of the seven impulses with the 432 recordings from 1978. Not only do they not say they checked all combinations, they don’t even seem to know how many possible combinations there are. They only refer to 2,592 combinations, not 3,024 combinations. There is no way they did manually check 3,024 combinations, but thought they had only checked 2,592.
Without a knowing which combinations where checked, and which were not, there is no way you or I or anyone can calculate the odds of “finding” the motorcycle seemed to be at the right place. That might only reflect them checking a limited number of microphones for each impulse.
Plus, how much faith can we put into what Dr. Barger said? Below is BBN Exhibit F-367
http://mcadams.posc.mu.edu/russ/infojfk/jfk2/f367.htm
Now, below, I quote from the same report you quoted from, just a few lines down:
There remain nine correlations that exceeded the detection threshold, and they occur at four different times:
Group 1.137.70 sec -- four correlations with test shots from the TSBD at Targets 1 and 3.*
Group 2.139.27 sec --three correlations with test shots from the TSBD at Target 3.
Group 3.145.15 sec -- one correlation with a test shot from the knoll at Target 3.
Group 4.145.61 sec -- two correlations with test shots from the TSBD at Targets 3 and 4.
*Possibly because of the presence of an overhead sign that interfered with test shots at Target 2, no correlations were found with that target.
Note the inaccuracies of the above paragraph, when compared with F-367.
With impulse 137.70, four correlations were not found from the TSBD and Targets 1 and 3.
Instead three correlations were found from the TSBD and Targets 1 and 3, plus a fourth correlation from the Grassy Knoll and Target 4.
With impulse 139.27, not just three correlations were found from the TSBD with Target 3.
In addition, a fourth correlation was also found from the Grassy Knoll with Target 3. But the BBN would just assume this inconvenient correlation go down the memory hole.
With impulse 145.15, not just one correlation was found from the Grassy Knoll with Target 3.
In addition, two more correlations were also found from the TSBD with Target 3. But again, the BBN would just assume that these inconvenient correlations also go down the memory hole.
With impulse 145.61, two correlations with test shots from TSBD at Targets 3 and 4 were not found.
Instead, three correlations with test shots from TSBD at Targets 2, 3 and 4 were found.
BBN just prunes away at the unwanted correlations that they wish they didn’t find from their final report. This is unacceptable. Also note the excuse they give for not finding a correlation with the test shot at Target 2. “the presence of an overhead sign that interfered with test shots at Target 2”.
The 1963 microphone can be right behind the motorcycle shield, totally blocking a direct path from the rifle to the microphone. But this still allowing correlations to be found with the rifle location, the target location and the microphone location.
But an overhead sign that is many of dozens of feet from the 1978 rifle, many of dozens of feet from the 1978 microphone, that can block out the sound waves, preventing a correlation from being found. But only when firing at Target 2. Not when firing at Targets 1 or 3.
And what did the NRC panel have to say about this powerful evidence? They argued that the BBN scientists had erred, that the BBN value of P<0.01 (i.e., less than 1%) should actually be P=0.07 (i.e., 7%), and that therefore the “significance of the layout” indicated by Figure 22 is “considerably reduced” (NRC report, p. 37). Alright, so instead of the probability of chance being less than 1%, the NRC panel said it is 7%.
Now, many readers will say, “Well, okay, but that means the NRC guys admitted that the probability that chance caused those correlations is only 7%, which means the probability that the police tape was recorded by a motorcycle in Dealey Plaza is 93%.” Indeed.
The NRC panel made no effort to explain the significance of the fact that their own calculation found a 93% probability that the locational correlations occurred because the impulse patterns on the police tape were recorded by a motorcycle in Dealey Plaza. In fact, they did not even specifically mention this. They simply noted that they determined the probability of chance was 7% and acted as though they had dealt a strong blow to the BBN report. Granted, a 7% probability of chance is much more than a <1% probability, but it is still an extremely low probability.
On a side note, the BBN report explains that not every recorded shot would have an N-wave (shock wave) in its impulse patterns because the microphone that recorded the shot was not in position to record it; but, if the microphone were in position to record the N-wave, the N-wave would be “a significant part” of the echo pattern:
As noted in previous posts, this is exactly what we see in the acoustical evidence: An N-wave appears in those dictabelt shots that were recorded when the motorcycle was in position to record the N-wave, and no N-wave appears in those shots where the motorcycle was not in position to record it (BBN report, 8 HSCA 49-50).
It seems that the motorcycle shield, or the torso of Officer McLain, should interfere with all the “N-waves”.
Finally, I want to return to this question of the extremely limited tests that Weiss and Aschkenasy made. I don’t know, but let’s say they were using computer punch cards. They made:
A. Computer program to compare any 1963 waveform with the theoretical waveform from many positions near a 1978 microphone. This has got to be 99% of the work.
B. 1 or more computer cards to represent the 1978 waveform from the test shot, from the grassy knoll, at target three, recorded from microphone 3 ( 4 ).
C. 1 or more computer cards to represent the 1963 145.15 waveform.
And ran the program to find the best location near microphone 3 ( 4 ) that would have given the best correlation, in theory.
This is fine. Now, after going through all that work, why not go the extra 1% and make:
B. 1 or more computer cards to represent the 1978 waveform from the test shot, from the TSBD, at target three, recorded from microphone 3 ( 4 ).
And run the same program again, this time with the 1978 TSBD waveform.
If this was done, what effect would it have on their final report, if they found a strong correlation for the Grassy Knoll shot, 4 feet up the street from microphone ( 4 ), but also found just as strong a correlation for the shot TSBD shot, 7 feet down the street from the same microphone?
Mr. Griffith generally dodges simple questions, but I will try it again. Never trust anyone who routinely dodges simple questions:
Question 1: What effect would it have had, on Weiss and Aschkenasy final report if they had done this, and found just as strong a correlation near microphone 3 ( 4 ) for the test shot from the TSBD as they did for the test shot from the Grassy Knoll? I would say it would have been really bad. How could the 145.15 waveform match up with both the Grassy Knoll shot and the TSBD shot?
Question 2: Why didn’t Weiss and Aschkenasy take the extra step, just slightly more work to punch out a few more cards, to run this correlation? I say it was likely because they feared, consciously or subconsciously, the two-correlation scenario I have described. Do you have a better theory?
By the way, I used to be a computer programmer from that era, so I know that preparing the data to be used was a fraction of the work of writing the computer program itself.