Thompson's New Book Powerfully Confirms the HSCA Acoustical Evidence

[Michael T. Griffith]

There was no expectation that they would publish Barger's letter in their report, and Barger's letter didn't contain anything that would debunk what the panel found.

Hogwash. Barger's letter, among other things, presented evidence that the Decker "hold everything" transmission had to be an artifact, not crosstalk.

And one would think that the NRC panel would have at least addressed the counter arguments that Barger presented in his letter, but they ignored them because they had no answer for them.

Quote from: Michael T. Griffith on January 30, 2021, 01:05:26 PM
I think it would be helpful to keep in mind that even the NRC panel admitted that there was only a 7% probability that the numerous locational correlations between the dictabelt gunshots and the test-firing gunshots were the result of chance (https://miketgriffith.com/files/hscaacous.pdf, pp. 12-13).

It wasn't random chance.  That doesn't mean there was gunfire.

More hogwash. I wonder if you understand what we're talking about here. The NRC panel was responding to BBN's powerful observation about the amazing locational correlations between the gunshot impulse patterns and the test-firing impulse patterns. By disputing one of the values that the BBN scientists assigned, the NRC panel reduced the probability of gunfire from over 99% to 93%.

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:

Even a brief glance at Fig. 22 shows that the microphone locations that correspond to correlations at the three times after the first impulse tend to progress uniformly forward along the motorcade route. This conclusion can be quantified statistically by the chi-square test. If the motorcycle were not moving through Dealey Plaza at the time of the assassination, the distance along the motorcade route would be a meaningless coordinate, and the microphone locations for the correlations that exceed the detection threshold would occur at random. When the chart in Fig. 22 is partitioned into a 2 x 2 table by separating time at 5 sec and distance at 250 ft, we find 1, 6, 8, and 0 correlations in the four sections reading from left to right, top to bottom. But the expected number of correlations to be found in these four sections, if the correlations occurred at random, are 4.2, 2.8, 4.8, 3.2. The value of chi-square for the observed and expected values is equal to 11.4. There is only 1 degree of freedom in this 2 x 2 table, and the probability that this large value of chi-square could occur at random is less than 1%. Therefore, there is little doubt that the distance coordinate is meaningful, and we conclude that the motorcycle was moving through Dealey Plaza and did, in fact, detect the sounds of gunfire. (BBN report, 8 HSCA 104)

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 during the assassination. In fact, they did not even specifically mention this. They simply noted that they determined the probability of chance was 7 percent and acted as though they had dealt a strong blow to the BBN report. Yes, 7% is more than "less than 1%," but it is still an extremely low probability of chance.

What makes the locational correlations especially powerful is that they show the correct pace and distance of movement that one would expect if the mic were on a motorcycle that was moving along the motorcade route.

[Michael ODell]

If you actually read the book, you'll see that Thompson commends O'Dell for his raw-data research, not for his claims about the data. Dr. Thomas has said the same thing: that O'Dell has done good raw-data work but that his claims about the data are wrong. By the way, Dr. Thomas spends several pages in Hear No Evil responding to O'Dell's claims.

Not really.  He responds to positions that I also may hold, but I don't think he responds directly to me much.

Thompson specifically cites my work with the recordings, that's true.  Of course you're only reading one side of an argument and don't know what was left out.  There was more than providing raw data.  The book, and Barger's work, have changed significantly from the early drafts because I had to explain to them multiple times where they were getting things wrong.  An entire section full of glowing praise, about when he came to visit me, was edited out.  Putting all that in would be boring, and wouldn't quite fit the story being told.  The point being, you don't have the full story.

Folks, go read Thompson's chapters on the acoustical evidence and also Dr. Barger's and Dr. Mullen's appendices, and then make up your own minds.

They can't really do that until they read the other side, which isn't available yet.

Michael

[Michael ODell]

Hogwash. Barger's letter, among other things, presented evidence that the Decker "hold everything" transmission had to be an artifact, not crosstalk.

No, it presented ideas Barger thought would be worth pursuing.  Nothing says those ideas would pay out.

And one would think that the NRC panel would have at least addressed the counter arguments that Barger presented in his letter, but they ignored them because they had no answer for them.

You are attaching too much significance to that letter.  There's no reason to expect the NRC to publish a response to a private letter.  And the letter wasn't a counter argument.

More hogwash. I wonder if you understand what we're talking about here.

Uh yeah, I do.

The NRC panel was responding to BBN's powerful observation about the amazing locational correlations between the gunshot impulse patterns and the test-firing impulse patterns. By disputing one of the values that the BBN scientists assigned, the NRC panel reduced the probability of gunfire from over 99% to 93%.

BBN/WA presented a probability calculation and the NRC panel responded to some of the math.  It's also true that the probability result was not the probability of a gunshot.  That's a basic error that BBN/WA made.  They were not "amazing locational correlations".  The parameters were loose enough to correlate to many possible patterns.

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:

After having removed correlations that didn't fit.

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 during the assassination. In fact, they did not even specifically mention this. They simply noted that they determined the probability of chance was 7 percent and acted as though they had dealt a strong blow to the BBN report. Yes, 7% is more than "less than 1%," but it is still an extremely low probability of chance.

It was not a 93% probability that that the patterns were recorded by a motorcycle in Dealey Plaza.  You are mis-stating the results.  That's not what the number meant, whatever it is.  Which is why whatever that number is does not matter.

What makes the locational correlations especially powerful is that they show the correct pace and distance of movement that one would expect if the mic were on a motorcycle that was moving along the motorcade route.

Again, after removing things that didn't fit.

[Mitch Todd]

If you actually read the book, you'll see that Thompson commends O'Dell for his raw-data research, not for his claims about the data. Dr. Thomas has said the same thing: that O'Dell has done good raw-data work but that his claims about the data are wrong. By the way, Dr. Thomas spends several pages in Hear No Evil responding to O'Dell's claims.

Folks, go read Thompson's chapters on the acoustical evidence and also Dr. Barger's and Dr. Mullen's appendices, and then make up your own minds.

Thompson still commends O'Dell in the book, and says nothing negative about him or what he's done.

As for Dr Thomas, he's in the same boat as Barger. Synchronizing the two channels on the assumption of an alleged "I'll check it" "crosstalk" requires channel 2 gaining time on channel 1 during a period where channel 1 is recording continuously and channel 2 is only recording intermittently. That is, at a time that channel 2 is not only  consistently losing time on channel 1, and where channel 2 cannot possibly gain time on channel 1. This is true if you compare alleged "I'll check it" event to "hold everything," "you want me," "Attention," or "I've got" events. The timing that Barger and Thomas assert simply cannot happen the way that they claim it did.

Folks, go read Thompson's chapters on the acoustical evidence and also Dr. Barger's and Dr. Mullen's appendices, and then make up your own minds.

I'm not sure how many readers are really going to understand the PCC part. That's a pretty esoteric subject. As for the timing and synchronization problem, I'd have them graph out the timing data given in the book, and analyze it for themselves.

[Michael T. Griffith]

Not really.  He responds to positions that I also may hold, but I don't think he responds directly to me much.

Thompson specifically cites my work with the recordings, that's true.  Of course you're only reading one side of an argument and don't know what was left out.  There was more than providing raw data.  The book, and Barger's work, have changed significantly from the early drafts because I had to explain to them multiple times where they were getting things wrong.  An entire section full of glowing praise, about when he came to visit me, was edited out.  Putting all that in would be boring, and wouldn't quite fit the story being told.  The point being, you don't have the full story.

They probably removed that praise when they realized that you are not dealing objectively and accurately with the acoustical evidence. Your claim that Decker's "hold" transmission is still crosstalk indicates a refusal to face obvious fact. There are three compelling indicators that "hold" must be, absolutely must be, an overdub, not crosstalk.

Similarly, your objectivity and credibility are called into serious question by your response to the NRC panel's admission that there's only a 7% probability that the locational correlations were caused by chance. To simply say "Well, that doesn't mean the impulse patterns are assassination gunshots" suggests a fanatical refusal to deal with the evidence forthrightly and credibly. 

And we haven't even talked about the remarkable correlations involving windshield distortions and N-waves. These are two more powerful evidentiary items that prove to any candid, objective observer that the suspect impulse patterns represent gunfire from Dealey Plaza during the assassination.

Nor have we talked about the WA sonar analysis of the grassy knoll shot. WA determined that the probability that chance caused the amazing correlations that they discovered was no more than 5% and was actually "considerably" lower than 5%. The NRC panel increased the probability of chance from 5% or less to 22% by making some clearly erroneous assumptions about key values. Dr. Thomas has demonstrated that if we use much more reasonable values than the ones the NRC panel used, the probability that chance caused the sonar analysis correlations plummets down to 1 in 100,000.

[Michael ODell]

They probably removed that praise when they realized that you are not dealing objectively and accurately with the acoustical evidence. Your claim that Decker's "hold" transmission is still crosstalk indicates a refusal to face obvious fact. There are three compelling indicators that "hold" must be, absolutely must be, an overdub, not crosstalk.

You assume that if I disagree with you that I'm not being objective.  That's not how it works.

Similarly, your objectivity and credibility are called into serious question by your response to the NRC panel's admission that there's only a 7% probability that the locational correlations were caused by chance. To simply say "Well, that doesn't mean the impulse patterns are assassination gunshots" suggests a fanatical refusal to deal with the evidence forthrightly and credibly. 

Called into question in your mind, but see above.  In fact,  I'm correct about that and it's you that needs to learn something about it.

And we haven't even talked about the remarkable correlations involving windshield distortions and N-waves. These are two more powerful evidentiary items that prove to any candid, objective observer that the suspect impulse patterns represent gunfire from Dealey Plaza during the assassination.

As an "objective observer", you must have done something to demonstrate the existence of these N-waves.  Please post it here.

Nor have we talked about the WA sonar analysis of the grassy knoll shot. WA determined that the probability that chance caused the amazing correlations that they discovered was no more than 5% and was actually "considerably" lower than 5%. The NRC panel increased the probability of chance from 5% or less to 22% by making some clearly erroneous assumptions about key values. Dr. Thomas has demonstrated that if we use much more reasonable values than the ones the NRC panel used, the probability that chance caused the sonar analysis correlations plummets down to 1 in 100,000.

But I have talked about that, and done more than talk.  It's not amazing at all.  And as already mentioned, that probability calculation is not the probability of a shot from the grassy knoll.  They are wrong about that.  And you have a lot to learn about the subject.

[Michael T. Griffith]

It might be helpful to point out that Michael O'Dell also denies there is acoustic evidence of multiple gunmen in the RFK assassination, and that he is in the minority among acoustics experts who have studied the recording. The experts who've determined that the recording contains many more gunshot impulses than Sirhan's gun could have fired have far more experience and qualifications than O'Dell has. I just thought this would be worth noting.

[Paul J Cummings]

Also acoustics won't demonstrate shots firing at the same time nor the obvious silencers that may have been used.