posted 05-07-2009 08:52 AM            

Have convinced powers that be, that we need new equipment.

Anyone have any thoughts on whether Limestone or Stoelting are better than Lafayette and why.

Your input would be most appreciated.

------------------
Willis

"No matter who says what,
don’t believe it if
it don’t make sense."
Bix Bender

posted 05-07-2009 11:05 AM            

I'm normally opposed to a lot of smack-down discussion about instruments in this forum, mainly because I like discussion that is free of marketing and other head-spinning nonsense.

The instrument manufacturers and reps have access to this forum, but have been asked in the past to mainly lurk.

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However, we all need cheap entertainment these days, and there are some incremental improvements and developments in the systems.

So, I propose we considering giving the instrument reps a one-time-special-dispensation to tell us what is great about their systems.

We can fill in the discussion with detail about what we like and what the niggles are with system.

Ralph?

r

------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)

posted 05-07-2009 04:19 PM            

Sounds like a well balanced suggestion. Whichever vendors are lurking...feel free to make one sales pitch post in this thread and answers to any direct questions that follow.

------------------
Ralph Hilliard
PolygraphPlace Owner & Operator

Be sure to visit our new store for all things Polygraph Related
http://store.polygraphplace.com

posted 05-08-2009 12:15 PM            

Remember to write a manual for OSS-3.

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For anyone not familiar with the details and features of OSS-3, the aqua shaded areas are marked artifacts that will be moved from the analysis. Just check the boxes at the right side of the screen to remove an artifacted measurement from the score.

By default, the Lafayette OSS-3 tool will not score a test until you have scrolled through and looked at every question.

OSS-3 and our present array of computer algorithms cannot be expected to score garbage. Remember: garbage in = garbage out.

If you wouldn't score it, then you should not let the computer score it.

All the computer does is a bit of fancy math for you - so we can have a scientific statistical classifier, based on inferential statistics and signal detection theory. The value of this is that is that it brings us into the realm of science, and gets us beyond the 2nd grade math and simple point total or sorting procedure as a basis for polygraph decisions. Scientific tests must be supported by recognizable statistical models - otherwise we remain vulnerable to accusations that polygraph is somehow not scientific.

Here is a graphic

In addition to removing a marked artifact from the statistical analysis, OSS-3 will use an equation called the Test of Proportions (an algorithm within the algorithm) to count the number and location of artifacts, and calculate the probability that they fit a pattern that would be expected if they are occurring by random chance alone.

If the probability is very low that they are random, then nonrandom-artifacts = possible-countermeasures.

You will see the information on the OSS-3 report

The Limestone OSS-3 has the same features, though reviewing and artifacting is performed in the normal Limestone chart viewer instead of a separate tool.

And the same information on the report. In this clip you can also see that artifact marks are displayed for auditing in the measurement table. This alerts a reader or reviewer to the fact that the examiner marked an artifact at a measurement. Of course, absence of any artifact marks in the measurement table signifies that the examiner was satisfied with the interpretable quality of the data.

r

------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)

posted 05-08-2009 06:30 PM            

I was the guy who asked for the aqua blocks.

Ok, cowboy, what are the different size yellow blocks ?. It looks is marking the critical zone, but I´m not sure.

By the way, still waiting for the OSS3 manual.

Best,

------------------
Hól vagytok székelyek, e földet biztam rátok.
Elvették töletek,másé lett hazátok.
Vesszen Trianon !

posted 05-11-2009 05:40 PM            

One thing I like about the Stoelting is that it records the raw data and then re-displays it optimally on the screen for scoring. I can make any adjustments to the data as I'm collecting it but it doesn't change the raw data, only the "picture" of the data I can see. When it's redisplayed, it each channel of data neatly fits in its piece of "real estate" (so it doesn't overlap with other channels), and all the ratios are retained so I know exactly how much bigger one reaction is than another.

Limestone does things differently. It works more like an analog when you record the data. However, when you increase the gain, it increases all the way back to the BEGINNING of the chart, so you can make adjustments any time you want with no fear of messing things up, which is a nice feature.

Lafayette looks very much like an analog when it comes to such adjustments, making it easy for anybody see what you did and when.

Stoelting and Limestone record skin conductance, and Lafayette (I think) records skin resistance.

Lafayette has a detrend feature on the EDA. Limestone (I think) and Stoelting allow for filtering if you desire, and Stoelting has a detrend option as well; although, it's different from Lafayette's.

Etc, etc, etc.

posted 05-11-2009 06:56 PM            

Polygraph software and instrumentation could be compared to choosing an automobile. They will all deliver a comparable result. I may be a little biased but I believe we offer the Lexus. Our software is feature rich and “Rock Solid”. You will not be hampered with unexplained software glitches and if there are any problems they will be rectified immediately. For obvious reasons you should make sure that your solution provider meets ASTM standards.

If after sales support is important to you I can personally guarantee you that Limestone Technologies will be there for you long after the sale is complete. Service is number one at Limestone and if a client isn’t getting the prompt service and respect they deserve they’re welcome to call me directly. 613.634.2594 ext 201

Contact our sales team if you would like more information about the products and services we offer. sales@limestonetech.com or sue@limestonetech.com

--
James S. Brown
President
Limestone Technologies Inc.

posted 05-12-2009 11:03 AM            

The Limestone system, like the Stoelting, does not change the originally recorded raw data when you make any post-hoc changes or annotations (after the exam is completed). Post-test review is performed on a copy of the original raw data. You can always go back to the original raw data. This is a common concern and common practice for researchers.

I'd guess the Lafayette does the same thing.

Axciton also does this. You can removed all post-hoc changes and revert to the original display of the raw data.

The difference will be that the Stoelting and Limestone systems store data in an ASCII format that is accessible and usable to researchers. You can open the data with a text-editor or spreadsheet, and import the raw data to a statistical software for analysis.

Here is a screen-shot from an exam I ran yesterday.

Keep in mind that what we look at is NOT the data. We look at pictures of the data. Data are the numbers and measurements themselves.

Here is the raw data from the same exam opened in a common spreadsheet.

And a plot of the 15 second cardio segment at C5.

A niggle with the Lafayette system is that the original raw data is stored in a proprietary binary (computer-eze) format that cannot be read by humans and is useless to researchers. You cannot open the raw data. There is a feature to store the raw data in ASCII format. However, it is buried in the dark recesses of the preferences sections, and is turned "off" by default. The decision to leave it off was probably the result of concern for storage space in years past. Nowadays, computer storage space is dirt cheap, and there is no reason not to store the raw data in ACSII format that is usable to researchers. A related problem is that if the raw data are not stored at the time of the examination, there is no feature to get the raw data afterward. It's too late.

Lafayette's OSS-3 tool will export the raw data to ASCII format, but will only work with CQT exams for now. There is no way to obtain or study the raw data from CIT or RI or any tests that cannot be scored with OSS-3.

An argument against ASCII storage may be that it can be altered. This is silly, and suggests that examiners cannot be trusted to refrain from altering the data. It is also negligent of the fact that there are easy ways of auditing any changes, and always saving the original raw data for comparison.

Lafayette's store raw data in ASCII format should be 'on' by default.

The Axciton situation is even more frustrating.

The data are stored in a proprietary binary format, and there appears to be no way to export or obtain the raw data without some expensive and and convoluted reverse engineering. The raw data really should be available to polygraph researchers - in ASCII format.

This is frustrating, because we have an archive of confirmed cases that were collected with the Axciton system. Unfortunately we are not able to make much use of the data, because we can't get to it. We get pictures of the data on the screen, which are of little use to researchers. All polygraph systems should provide data that is suitable for research and the advancement of scientific polygraph testing. Proprietary research is OK, but doesn't serve the long term need of the polygraph profession and instead tends to encourage dependency on some proprietorship (not sure if that is an actual word, but we'll go with it for now).

There have been some things accomplished with this data - primarily as a result of an external tool developed by John Harris (the developer of Polyscore) for the Dept. of Defense. That tool obtains the Kircher measurements from Axciton and Lafayette charts.

All polygraph systems should provide the Kircher measurements, which are well established by 20+ years of study as simple and robust features. It makes no sense to neglect our own science.

Stoelting provides Kircher measurements in there algorithm report. Limestone will export Kircher measurements from any exam from within the Limestone Chart Viewer. Lafayette will now export the Kircher measurements to an ASCII file from the OSS-3 tool. Again, this is only possible with CQT exams, which hinders the study of other techniques. Lafayette will hopefully someday include this feature in the LX software. Why all the fuss about science, you ask? Because if we don't concern ourselves with science, then we cannot expect to be taken seriously in court or by other scientists, and we will be vulnerable to critics who want to attack us as being unscientific.

Science is explainable and point-to-able.

If you had to argue a test in front of others and in the face of an articulate critic, it would be a lot easier to prevail if you could show the published studies and citations that demonstrate why and how certain methods and certain features work. Then point to those features in the data, for all the skeptics and critics to choke on - 'cause you'd have to be a moron to miss it.

Then show the result, and level of statistical significance, based on some documented and published mathematical procedures.

And because good math and good science is both describable and repeatable, here are the data after I copied the ASCII values from the Lafayette system and pasted them into the spreadsheet used in Limestone OSS-3 system.

To quote Mike Lynch in the recent APA magazine "numbers are numbers."

.02

r

r

------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)

posted 05-12-2009 11:48 AM            

Until you are able to provide heated countermeasure cushions upholstered in fine Corinthian leather, comparing your instrument a Lexus is somewhat premature.

I have held off quite a while before putting in my 2 cents worth on this topic because discussions regarding polygraph instruments seem to engender loyalties nearly as fierce as ones basic polygraph school.

When I purchased my last polygraph instrument, I was already using an Axciton and was more than familiar with their instrument and service department. But since I was spending MY OWN MONEY I wanted to insure that I made the right decision. I wanted to purchase from a company that
#1 had a history among my peers of reliability and quick technical support response. Lafayette, Limestone, and Stoelting pulled ahead of Axciton. I'm not saying anything was wrong, I just think the others were better.
#2 I wanted an instrument with a user friendly interface. Limestone and Lafayette, pulled ahead of Stoelting here although it may have had more to do with the person demonstrating the software than any problems that really existed.
#3, Even though I wanted a company with proven reliability, I also wanted a company who was working diligently to improve data collection and analysis.

At the time, and based on personal preferences Limestone was the company that got my hard earned dollars. I have not regretted my decision at all.

If you are buying a new instrument, I suggest you:
A. Observe and participate in a hands-on Demo of each system under consideration.It is much better to do this privately than at a display table at a conference.
B. Talk to examiners who actually use each type of instrument. Most will be happy to tell you what they like, but be sure and press them until you get at least one thing they dont'like.
C. Make up a list of questions and call the service department for each manufacturer under consideration. Be sure and include some questions to find out if they know anything about polygraph or are just Computer/Electronics geeks. (not that geeks are bad, but there can be communication problems)
After all is said and done I don't think you will make a bad decision.

posted 05-12-2009 03:10 PM            

With all that has been relayed, both here and in private emails and phone calls, the decision has been made.

Again thank you Ray for the OSS tutorials. I hope to get more, as the new equipment comes with OSS 1, 2, and 3.

Thanks again to everyone

posted 05-12-2009 06:10 PM            

YL,

Part of the fun, aside from the new instrument for you, is that we can all learn a bit about the features of each system. OK, a good smack-down-tag-team argument would also liven up a dull forum. Plus, developers may learn more about what we like and what we need.

r

------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)

posted 05-12-2009 08:56 PM            

Your positive comments are important feedback for team Limestone. They confirm that we’re doing a good job. Our team is here to listen and it will never be our intention to dictate to examiners how their software and instrumentation should function. The success of Limestone can be attributed to a positive exchange of information between examiners and software engineers. We do not march to our own beat and we do not try to emulate our competitors. Our mutual cooperation guarantees a great product. We back this up with outstanding customer support. It’s a pretty simple formula.

Did you want heated countermeasure cushions that are upholstered in fine “Red” Corinthian leather? Is this for you or the examinee?

Do you mind if I add your positive comments to our testimonial page? http://www.limestonetech.com/testimonialsPolygraph.php

Sincerely,

posted 05-12-2009 09:48 PM            

------------------
Ralph Hilliard
PolygraphPlace Owner & Operator

Be sure to visit our new store for all things Polygraph Related
http://store.polygraphplace.com

posted 05-13-2009 09:06 AM            

Short skirts can hurt a lot.

They are powerful weapons to be used carefully by responsible adults.

We should perhaps license and regulate the things.

.02

r

------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)

posted 05-13-2009 09:27 AM            

I think an oversight committee may be an alternative though. I would gladly volunteer my time to ensure proper length and content.

------------------
Willis

"No matter who says what,
don’t believe it if
it don’t make sense."
Bix Bender

posted 05-13-2009 10:26 AM            

I think that some method of attaching a CM cushion temporarily to a chair so it wouldn't slide around, would be an inexpensive innovation that would be especially appreciated by us "Have Polygraph, Will Travel" types.

If you need another endorsement... I think Limestone hands out absolutely the BEST free mouse pads in the business; surpassing Stoelting and their other competitors by a Canadian Country Mile. Unfortunately my spare has disappeared, apparently surreptitiously misappropriated by someone who could see its obvious quality, and my current one is finally almost worn out. hint Hint HINT

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Ex scientia veritas

posted 05-13-2009 10:37 AM            

BTW - Tyler and I discussed your suggestion of a Velcro strap on the counter measure cushion this morning and we have some ideas that will address this concern.

Cheers,

JB

posted 05-13-2009 02:10 PM            

Jim

posted 05-13-2009 08:04 PM         

If that was a model, who ever hired her should either ask for a refund or get their eyes checked!

posted 05-17-2009 03:01 PM            

she was a local hire to try and make Bruce look better; I guess from that perspective it's possible. I spoke with her for a few minutes at the booth and she verified her "local" status and indicated to me she was "learning" about polygraph.

Ooooooohhhhh Yeeaaaahhhhhhh...

He's been trying oh so very hard after pushing Sue out the door. I say good free frickin luck!