Merged Discussion of femr's video data analysis

[alienentity]

ROFL. You can't read the graph properly is the problem.

I CLEARLY state and label the x axis...Datapoint PAIR.

I can indeed read the graph. Don't be childish.

You seem to think NIST plotted datapoint spacing somewhere. They didn't. "The NIST graph does a better job of presenting the data

Their points are all presented as points. Yours are not. That is why theirs is clearer.

I understand that you cannot see other people's viewpoints. That's ok. It's just the way you are.

 

[femr2]

I can indeed read the graph. Don't be childish.

Then you shouldn't be saying inept nonsense such as...

you didn't plot the first datapoint at T=0. NIST does put their first point there in 12-76.

Their points are all presented as points. Yours are not. That is why theirs is clearer.

The two graphs are showing different information.

One is NISTs position/time graph, the other is a graph of the amount of time between each pair of datapoints on that graph. Clearly stated to you, repeatedly misunderstood by you.

Datapoint pair 1 on NIST Figure 12-76 (which is the pair of datapoints T=0 and T=0.86) has the value...0.86 on my graph.

You managed to accept that there's no data between T=0 and T=0.86 yet ?

 

[alienentity]

Then you shouldn't be saying inept nonsense such as...





The two graphs are showing different information.

Uh, no, they do not. It's the same information presented in a different format - however you removed the displacement data in your version.

But whilst we're on the subject of plotting, your graph is weaker based on two points, actually:

1) Unlike the NIST data, which is presented with a black point for all the datapoints, yours omits the first one.
2) All data points are connected on the NIST graph, whereas yours is missing a red line to connect with the nonexistent first datapoint.

If you were presenting this at a lecture, it would be very confusing to most people at first glance. I suspect you haven't done much public presentation, because you wouldn't present your data that way if you had.

Perhaps I'm wrong, and you're a college professor. I do give lectures and masterclasses, and clarity is very helpful..

 

[femr2]

Uh, no, they do not. It's the same information presented in a different format - however you removed the displacement data in your version.

ROFL. Just stop eh. No, it's not the same information. 12-76 is a position/time graph, mine is a datapoint separation/datapoint pair graph. Different information.

But whilst we're on the subject of plotting, your graph is weaker based on two points, actually:

1) Unlike the NIST data, which is presented with a black point for all the datapoints, yours omits the first one.

ROFL. Each of my points, again, is for a datapoint PAIR.

You'll get there eventually

2) All data points are connected on the NIST graph, whereas yours is missing a red line to connect with the nonexistent first datapoint.

ROFL. See above.

clarity is very helpful..

The graph is perfectly clear.

 

[Major_Tom]

I'll put the matter another way - the exact N/S motions are unknown. Determinations are inconclusive contrary to the claims of some; added to this the limited resolution of the videos and therefore data derived can only be used as estimations for general purposes.

In my view so long as the measurements fall within a reasonable range of accuracy and are recognized to be inherently inexact, they are useful.
Approximate collapse times may vary by 1 second or more, depending on the method of measurement. This does not in itself invalidate the major engineering conclusions of the main investigation done by NIST.

Why don't we just take better measurements instead? Already done!



That is correct. N/S motions are unknown so be wary of NIST camera 3 early motion.

And that is the moral of the story.

Great advice for WD Clinger and TFK. Very important to know. Guys, like AE is pointing out, be wary of early camera 3 motion, the one the NIST used.

If you understand the "kink" as a 3-D fold that cannot be seen in the Dan Rather video but is .......like.......really big in the camera 3 view, we are ready to progress.


Think kink!

 

[alienentity]

ROFL. Just stop eh. No, it's not the same information. 12-76 is a position/time graph, mine is a datapoint separation/datapoint pair graph. Different information.

Hmm, and the datapoints just happen to be in the same positions as the NIST position/time graph?

ETA NIST calls theirs 'Velocity data points', you call yours 'datapoint pairs'. They are the same datapoints.

I see. You label it differently, so it's now different information. Wow.

ROFL right back atcha.

 

[femr2]

Hmm, and the datapoints just happen to be in the same positions as the NIST position/time graph?

I see. You label it differently, so it's now different information. Wow.

ROFL right back atcha.

O. M. G.

Figure 12-76...

My datapoint pair separation graph...

"the datapoints just happen to be in the same positions as the NIST position/time graph?" ???

Wow.

 

[alienentity]

Hehe. Dude, give it up. It's the same info.

21 datapoints spread out in exactly the same time intervals in both graphs. Identical info, minus the displacement data. Hello? Anyone home?

 

[femr2]

Hehe. Dude, give it up. It's the same info.

21 datapoints spread out in exactly the same time intervals in both graphs. Identical info, minus the displacement data. Hello? Anyone home?

Remember I suggested you take your time ? You really should have taken my advice.

Again...

O.M.G.

Oh the irony.

My graph shows the interval between each pair of datapoints in Figure 12-76. You should note that it is not a straight line, indicating that the separation is not constant.

One shows position/time data, the other separation/datapoint-pair.

It's really not difficult.

You are making an utter fool of yourself.

I suggest you stop. Take your time.

Can you imagine the number of laughing dogs that would be on this page right now if our places were reversed ? You should be grateful I'm not that sad. But STOP. Take your time. Realise how silly what you are saying is, state your mistakes, then move on.

I have better things to do with my time. This is nonsense.

 

[W.D.Clinger]

There are three possible explanations for what Major_Tom has said above and below:

1. I have made the statement he alleges but have forgotten all about it, which seems unlikely.
2. Major_Tom just made it up.
3. Major_Tom is just confused.

Since Major_Tom can't seem to come up with a direct quote, everyone should assume some combination of explanations 2 and 3.

Your earlier comments comparing the results of the NIST with the results of femr seem pretty meaningless unless you ignore the problems outlined in the last 2 pages.

Major_Tom has just confirmed that explanation 1 is not the correct explanation, so the explanation must be some combination of explanations 2 and 3.

And what do you make of the arguments of Femr2 and MT regarding the angle of the CBS footage?

I haven't been following your back-and-forth with femr2 in detail, so I don't know exactly what you're asking, but I'm unlikely to have an opinion. Some of femr2's claims are spot on, some of femr2's claims are false or nonsense, but most of femr2's claims are so inconsequential that the effort needed to form an opinion cannot be justified.

You really are making a bit of a fool of yourself you know. This is trivially simple stuff. Wasting my time because you can't eveb read a graph ? Jeebus.

A lot of the problem here is that femr2 posts graphs instead of numbers, forcing anyone who cares to reverse-engineer the numbers from which he constructed his graphs.

The level of accuracy is perfectly adequate for the purposes of an engineering report on structural failure.

True.

ROFL. Just stop eh. No, it's not the same information. 12-76 is a position/time graph, mine is a datapoint separation/datapoint pair graph. Different information.

False. The information in femr2's graph is a proper subset of the information in NIST's Figure 12-76.

In other words: All of the information in femr2's graph is already present in NIST's Figure 12-76, but Figure 12-76 contains additional information that is not present in femr2's graph.

That does not imply that femr2's graph is entirely worthless, because a graph that displays some particular aspect of Figure 12-76 while suppressing irrelevant details may help viewers to understand some particular point that femr2 might be attempting to make. In this case as in many others, however, femr2 relied overmuch on others' ability to infer the meaning of his graph from an overly succinct caption instead of augmenting his graph with a clear statement in prose of what the graph shows.

I have to agree with alienentity on this point:

If you were presenting this at a lecture, it would be very confusing to most people at first glance. I suspect you haven't done much public presentation, because you wouldn't present your data that way if you had.

 

[alienentity]

Remember I suggested you take your time ? You really should have taken my advice.

Again...

O.M.G.

Oh the irony.

My graph shows the interval between each pair of datapoints in Figure 12-76. You should note that it is not a straight line, indicating that the separation is not constant.

One shows position/time data, the other separation/datapoint-pair.

It's really not difficult.

You are making an utter fool of yourself.

I suggest you stop. Take your time.

Can you imagine the number of laughing dogs that would be on this page right now if our places were reversed ? You should be grateful I'm not that sad. But STOP. Take your time. Realise how silly what you are saying is, state your mistakes, then move on.

I have better things to do with my time. This is nonsense.

That's so weird. You extract datapoints from this NIST graph, regraph them in a different format, and then claim it's different information. Good God, how do you get along with other people in life?

No, it isn't. Period. You're the one who's wasting my time.

ETA ok, ok, I'll give you one point for making the graph which shows the NIST data in a different way. Does that make you feel better?

 

[femr2]

False. The information in femr2's graph is a proper subset of the information in NIST's Figure 12-76.

Therefore showing different information, much like a derived velocity graph shows different information than a displacement graph from which it was derived. One can be derived from the other, but the information is different.

I agree that it's information extracted from 12-76 of course.

however, femr2 relied overmuch on others' ability to infer the meaning of his graph from an overly succinct caption instead of augmenting his graph with a clear statement in prose of what the graph shows.

Incorrect. I've stated such prose directly to AlienEntity repeatedly, and he's still in la-la land.

Hmm, and the datapoints just happen to be in the same positions as the NIST position/time graph?

O.M.G.

 

[femr2]

You're the one who's wasting my time.

...

Hmm, and the datapoints just happen to be in the same positions as the NIST position/time graph?

21 datapoints spread out in exactly the same time intervals in both graphs. Identical info, minus the displacement data.

ETA NIST calls theirs 'Velocity data points', you call yours 'datapoint pairs'. They are the same datapoints.

Unlike the NIST data, which is presented with a black point for all the datapoints, yours omits the first one.

All data points are connected on the NIST graph, whereas yours is missing a red line to connect with the nonexistent first datapoint.

But the fact is you didn't plot the first datapoint at T=0. NIST does put their first point there in 12-76. You see? I really do understand.

Uhm, using your own timescale (1second interval), unless you've graphed it incorrectly, datapoint 1 to datapoint 2 are about .6 seconds apart.

Where is the datatapoint at T=0? Oh, it's missing. I checked 12-76 I see it is there in that graph.

Figure 12-76 in NCSTAR 1-9 doesn't look like the graph in your post!

I can indeed read the graph. Don't be childish.

etc...

ROFL.

ETA ok, ok, I'll give you one point for making the graph which shows the NIST data in a different way. Does that make you feel better?

Your recent, er, thought process is in this thread forever more. Does that make you feel better ?

 

[W.D.Clinger]

False. The information in femr2's graph is a proper subset of the information in NIST's Figure 12-76.

Therefore showing different information, much like a derived velocity graph shows different information than a displacement graph from which it was derived. One can be derived from the other, but the information is different.

I agree that it's information extracted from 12-76 of course.

So we can add information theory^WP to the list of technical concepts you think you understand but don't.

 

[femr2]

So we can add information theory^WP to the list of technical concepts you think you understand but don't.

You can attempt to provide AlienEntity with a vague *get out clause* as much as you like, but it won't stop his woeful 2 pages of stupid being a woeful 2 pages of stupid

Can you imagine how many laughing dogs you'd have used by now if the discussion had been the other way aound ?

That kind of response bias^WP is very enlightening you know

Anyway...

No data between the NIST T=0 and T=0.86s.

 

[W.D.Clinger]

Anyway...

No data between the NIST T=0 and T=0.86s.

Agreed. Yet NIST's model is more accurate than your polynomials between 11s and 13s (on your time scale).

There's a reason for that and a conclusion to be drawn, but neither you nor Major_Tom have yet figured it out, even after Myriad and I have posted lucid explanations.

 

[carlitos]

All the graphs are titled and labelled clearly.

LOL. "Datapoint pair" and "separations" are super-clear axis labels. Good luck passing a basic math class.

ETA - I was reminded of this exchange, which came after more than one label-less graph. femr2 cannot admit error, so I'll stipulate that it was my fault for not understanding his wisdom.

Just FYI, in the real world, every graph you produce should have X and Y axes clearly labeled, and a legend should list what the lines mean. Extra stuff like green lines to denote "mini jolts" should be labeled as such.

Seriously, have either of you gone to high school?

FYI - It was a graph produced ages ago for a private discussion at the911forum, where everyone involved was totally clear about it's context. Allowed for displaying a higher fidelity graph in the same space. Happens in noise-free discussion within which everyone knows what's being discussed. I suppose I could regenerate it for those as need, but it's not a high priority. Am sure MT could be convinced to add the explanitory text above when referring to the image in future.

If you (or anyone else) want to post graphs, then please label them. Simple. No need to be defensive. This is common courtesy. If you are accustomed to posting at a place where people don't label graphs, then that has apparently reinforced a lack of awareness on your part. Label the graphs, please.

 

[femr2]

Agreed. Yet NIST's model is more accurate than your polynomials between 11s and 13s.

My Poly(10) curve is invalid before T=11.8785s, as you well know. Feeble underhand assertion. Literally grasping at straws. As I said, I can generate a Poly(10) parameter set that IS valid before that time, but that is outside the ROI.

There's a reason for that

See above.

 

[W.D.Clinger]

My Poly(10) curve is invalid before T=11.8785s, as you well know. Feeble underhand assertion. Literally grasping at straws. As I said, I can generate a Poly(10) parameter set that IS valid before that time, but that is outside the ROI.

I recommend that exercise. By comparing the acceleration curve (second derivative) of that new tenth-degree polynomial to the corresponding second derivative of your Poly(10) polynomial in the neighborhood of 11.88s, you might actually learn a little bit of what Myriad and I have been trying to tell you.

But that's probably not the way to bet.

 

[femr2]

I recommend that exercise.

Perhaps.

you might actually learn a little bit of what Myriad and I have been trying to tell you.

I'm fully aware of Runge's_phenomenon^WP, but as you've said yourself, "spectacularly accurate on the evaluation data that overlap with its training set". Comparison with the S-G curve shows good behaviour of derived curves within the ROI also.