posted 01-30-2008 09:14 PM            

Has anyone had experience with Lafayette's LX5000?? Even for trial test purposes?

posted 01-31-2008 08:16 AM            

I'm sure a lot of people have a lot more thoughts and feelings about his, but don't want to alienate others.

So how to get the conversation going...

We could have an official polygraphplace.com marketing moment and invite the instrument manufacturers (who are probably always lurking) to tell us about their merits of their products. We might also start by asking examiners to tell us about the best features of the instrument - everything they really like. Then, to get some improvement ideas into the air, we could ask examiners to politely describe what they dislike about, or are disappointed about, the various instruments.

It might be fair to say that none of them are terrible and don't work, but for field examiners its hard to see through marketing fog. This is probably true in any field, just look at the American auto industry, and the computer software industry.

- more later.

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

posted 01-31-2008 12:58 PM            

and I'll promise to sit on my hands...

unless someone says something inaccurate, misleading, or disparaging to someone else's favorite instrument.

Funny thing is that I think we all learned from the last round. Shawn from Stoelting provided some information that was very interesting.

I later met Shawn at APA. He's a great guy - smart, educated, and ful of all kinds of knowledge. I later had a very enjoyable conversation with him over the telephone.

At the very least we could hear from examiners regarding the merits and limitations of their instruments.

Good physiological data data is the heart and soul of the polygraph. What makes data good (besides pretty pictures on the screen)? Good signal to noise without unnecessary or unaccounted for filtration or alteration of the data.

The other thing that has become apparent to me is the value and importance of storing the physiological data in a way that is actually useable beyond making pretty pictures of the data on the computer screen. The best solution would be to store physiological data in a way that is easy to import into a spreadsheet or statistical analysis software, including all data and event markers - without decoding, translation or interpretation. That means some form of ASCII or unicode data. XML sounds OK, but not for the large numbers of rows and columns of data that are generated when sampling four, five or more channels a many many times per second. .csv is ideal, as its been around forever, and is easily understood by anyone who wants to study or work with the data.

Undocumented proprietary binary data file formats have got to go. Computer storage space is cheap. Security is managed by the operating system these days. Anyone who claims the need for binary file formats for security reasons or storage space is proffering an excuse (lying). Lack of access to the data will continue to hold our profession back. What progress has been made is due in large part to our ability to access the physiological data and measurements via third-party tools, built under contracts, that do basic things like output Kircher measurements (a very small set of numbers representing the physiological data). This is so simple that its negligent of equipment vendors not to do it themselves. Things like Kircher measurements are documented in published research. Why wouldn't the equipment vendors want to suppport access to the physiological measurements, as described in the journals?

Better still would be some form of industry standard for the storage of data in a useable form. ASTM would be the ideal vehicle for that, but the committee is strangely silent about things like this, and other important topics.

Of course, features and technical support are important too.

OK, end of rant. (sitting on hands now).

r

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

posted 01-31-2008 01:07 PM            

quote:

---

Better still would be some form of industry standard for the storage of data in a useable form. ASTM would be the ideal vehicle for that, but the committee is strangely silent about things like this, and other important topics.

---

posted 01-31-2008 01:12 PM            

Sounds about time.

I'll go one step further, and assert that any instrument manufacturer cannot realistically claim their instrument suitable for research unless they provide the physiological data, including all physiology channels, timing-scales, and event markers in a form that is easily imported to a spreadsheet or statistical software package. Data that cannot be studied is essentially worthless.

(back to sitting on hands).

r

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

posted 01-31-2008 01:35 PM            

Stoelting
Lafayete
Axiton
Limestone

Thanks

posted 01-31-2008 02:59 PM            

Here are some graphics.

First the Axciton file structure. This is where the data are actually stored.

I've organized this into folders myself - by Examinee. Axciton stores everything in a single folder.

This is what you'll get if you try to open the data itself. Not useful at all.

Here is the directory for Stoelting. Not Much different

Stoelting will output exam data to ASCII format - this is really important.

Stoelting also makes the Kircher measurements available in their text-file report. You have to work to get them, but you can get them. Some of the work can be automated.

The Lafayette directory.

And the binary data file - argh!

To be fair, they provide the ability to record ascii data, but it is OFF by default. It should be ON by default, because the do not provide the ability to go back and get the data later.

Lafayette's very patient and intelligent programmer Kevin has given me a debug version that can do this, but it should be a standard feature.

The great thing about ascii data is that us humans can do things with it.

The only ongoing limitation for Lafayette is that they do not output a time-scale or list of event markers. So, it still does us very little good - because we can't define when things happen.

Another limitation (for researchers and number crunchers) is that although Lafayette includes an OSS-2 tool, they do not output the Kircher measurement data in any location that I can find.

This is easily fixed, and will hopefully be addressed soon.

Most of us will recognized this as a pneumo segment.

Here is a screenshot of the Limestone directory.

You can see they provide an event list that is easily available.

The Limestone data is easy to access and understand - and includes a time-scale for each component.

Ascii data is easy to plot and study.

And Limestone provides ascii output of the Kircher measurement data.

Enjoy.

r

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

posted 01-31-2008 03:04 PM            

The new DACA format (PDDRFRMT) will allow researchers and examiners to view charts produced by any vendor's instrument as long as your vendor's software allows you to import and export in PDDRFRMT.

I hope this helped!

posted 01-31-2008 03:13 PM            

Hiya Shawn.

Looking at pictures of data as charts on screen is not the same as having access to the numerical data.

Thanks for the info.

r

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

posted 01-31-2008 03:19 PM            

Looks like my last cell phone bill.

posted 01-31-2008 03:28 PM            

Nobody really likes looking at that stuff.

But its good to know its there.

If we don't plan and think ahead, then a lot of time goes by without doing much study or learning. Then we get criticized for not keeping pace with other fields of science.

So, its important that our equipment developers and vendors provide us with gear that can play nice with others.

Access to our own data, means that interested people get to do something productive.

r

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

posted 01-31-2008 07:20 PM            

Stoelting has always been more than good to me. They paid for a family cruise for me last summer, with tickets to a Dolphins game.
I hear Axciton has Subway Sandwich coupons though.

lol

posted 02-01-2008 09:23 AM         

I use Axciton for the quality programs and the high quality customer support. Yeh...that's the ticket!