>Date: Thu, 17 May 2001 15:02:35 -0700 (PDT)
>From: Dick Simpson 723-3525 <rsimpson@magellan.stanford.edu>
>To: rsimpson@magellan.stanford.edu, showalter@ringside.arc.nasa.gov
>Subject: VG_2801 Review
>
>Review Comments on VG_2801 from Dick Simpson (2nd try)
>======================================================
>
>  This is not very comprehensive, but I tried to sample.  And I didn't
>find much.  There's the question of PRODUCT_ID, where I believe you
>have substituted RING_OBSERVATION_ID to have an equivalent role.
>
>  Next time perhaps I won't lose my original set of comments.
>
>Dick
>
>
>VOLDESC.CAT
>-----------
>
>  Would it be better to have VOLUME_SET_ID =
>  USA_NASA_PDS_VG_2801_TO_2803 ? More generally, I was slightly
>  confused by the relationships among data sets, the data set
>  collection, volumes, and volume sets.  Each data set is on a
>  separate volume; the data set collection is the same as the volume
>  set.  There's nothing wrong here -- in fact, everything seems to be
>  correct; I'm just not used to seeing all these relationships spelled
>  out.  With regard to VOLUME_SET_ID, if there's no expectation of
>  adding more volumes, using the explicit range rather than "XX" could
>  be helpful.
>

The VOLUME_SET_ID has been changed as recommended.

>
>AAREADME.TXT
>------------
>
>  Use of DESCRIPTION to show original file name: could also use
>  ORIGINAL_PRODUCT_ID.

This was not changed. According to the PDS Data Dictionary, the
definition of ORIGINAL_PRODUCT_ID seems to mean something a little bit
different.

>
>  PPS Team members "as of 1986" -- are these their addresses as of
>  1986? Not sure what this means.  Linda Spilker was not a Spilker in
>  1986, and her MS today is different from that shown; Brad Wallis
>  also has a different M/S today.  But others (at JPL, the easiest to
>  check) seem to be OK.

I have added an explanatory note that we have updated contact
information.

>
>  Is there a generic Rings Node address/person where reports of errors
>  or difficulties could be sent?  Showalter may not be as active in
>  RINGS by the time this CD reaches local stores as he is now.

We don't have a generic contact address.  I added Mitch Gordon and the
Rings Node URL is also included.  That's about as much information as
we can realistically provide.

>
>
>CALIB/PN1C01A.TAB
>-----------------
>
>  PN1C01A.TAB:  I'm a little out of my element here, but ...  I'm not
>  sure what to make of a stellar-background correlation of -1 when all
>  of the input values are constant.
>
>  PN1CO2.TAB:  Similar comment here, though only the stellar signal is
>  now fixed.  But what is the point in correlating a quantity defined
>  to have a fixed value with something else?   And what does it mean
>  when that correlation turns out to be -1?
>
>  Other calibration files have similarly large negative correlations
>  when the input values are either fixed or vary almost none.
>

The numbers are highly anti-correlated because the only strong
constraint we have is on the sum of stellar and background counts. The
correlation parameter is useful to include because it can enter into
estimates of the systematic uncertainty in derived optical depths. The
fact that the estimates are constant (i.e., independent of time) is
not relevant to their uncertainties or correlations.

I have revised the DESCRIPTION field of this column to explain why
correlation values near -1 arise so often.

>
>CATALOG/DATASET.CAT
>-------------------
>
>  line 62: continues --> continuous

Fixed.

>
>  line 279: You will want to update the review status.

Done.

>
>  I like the way you have divided the data by levels of processing.
>  The short (e.g., 3-6 line) descriptions of each are just about the
>  right length.  Descriptions of ancillary data are equally terse yet
>  meaningful.
>
>
>CATALOG/SOFTWARE.CAT
>====================
>
>  My recollection is that keyword values should be in upper case
>  except for DESCRIPTION and NOTE.  Hence, the SOFTWARE_NAME values
>  that are in mixed case should be promoted to upper case.  I'm going
>  to be inconsistent by not raising objections to mixed case in
>  ON_LINE_IDENTIFICATION -- which probably don't meet the
>  recommendation that *.CAT files be limited to 72 character line
>  lengths either.
>

I fixed the SOFTWARE_NAMEs and (against my better judgment) line wrapped the
URL and converted it to upper case; with these changes, of course, it will
not work (but the Central Node insisted).

I left in a comment indicating the correct, case-sensitive URL.

>
>CATALOG/INSTHOST.CAT
>====================
>
>  I have a VG2 file dated 2000-07-26 which may be more recent than
>  yours.
>

We have replaced the INSTHOST.CAT file with your version.

>
>SOFTWARE/PROFILE/AAREADME.TXT
>=============================
>
>  line 14:   indendent --> independent
>  line 42:   include --> includes
>  line 111:  as in --> as an

All fixed.

>
>  lines 53-54: I don't understand.  What does packaging the software
>  with a given data set have to do with its list of enhanced features?
>   And what does that have to do with the contents of
>  SOFTWARE/PROFILE?  Perhaps these two lines could be omitted?

Done.