SNPWG5

jens 08:45, 30 August 2010 (UTC) One given task was to evaluate the necessity of having different levels of confidence of nautical information. This site is made to discuss this issue and to share different views on that. The discussion should be focused on the problem not on different portrayal options. The results will be presented for consideration to the DQWG meeting in Rostock Oct 2010. So we don't have much time.

The outcome of various BSH internal discussions is that we have developed two approaches:

1. Source related
2. Time related

1. If we consider different sources for Nautical Information and try to generalize as much as possible we come up with following different levels of confidence. The provided items base on German source confidence. Other HOs can add various others to complete the list.

1. authoritative (Legal bodies)
2. official (international organizations (e.g. ITU), other federal organizations)
3. not verified or not verifiable (e.g. reported, websites)

2. Discussing the same problem and taking time dependency into account. We might evaluate several options all with several pros and cons. One can follow the life circle of the relevant publication. That can be very different from one HO to another and nobody is checking all information in a pub every time when a new edition is scheduled. Only changes are recorded. The other can be a time line indicating when the source was recorded or revised. The latter makes sense if we refer to very old sources in particular and it separates the information from the publication. That is our preference. The SORDAT approach can be adapted. Using the chart-chart datum is source datum, using the HPD source datum is source datum. For an initial upload SORDAT of printed information and database can by similar. That will change afterwards.

1. 0-5 years old
2. 5-10 years old
3. older than 10 years.

It is unlikely that it will be necessary to track information older than 10 years more detailed.