Parcel Fabric, Feature Adjustments. . . How is the adjustment is performed?

[TravisSandeski]

Hi, I am wishing to learn more about what spatial adjustment is applied to my data, when applying the a parcel fabric feature adjustment.

http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/About_the_parcel_fabric_feature_adjust...
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Running_a_parcel_fabric_feature_adjust...

I understand the parcel fabric is adjusted using a least-squares method. The online help clearly says:

'When a set of parcels is adjusted in a fabric least-squares adjustment, vectors are generated between the old and new coordinates of the parcels. The parcel fabric feature adjustment uses these vectors to adjust and realign features in associated feature classes.'

I assume these vectors to be similar to that of any displacement link created in the software, with a from and to coordinate.

Are 'vectors'' are also generated for vertices that didn't shift (i.e. control link), and/or for vertices that do not fall on a parcel boundary (i.e. control monument)?

When ArcGIS uses these vectors to perform an adjustment on a separate feature class, what type of adjustment is performed (is it utilizing the rubber sheet adjustment to force re-alignment to the parcel fabric or some other algorithm)?

Rubber Sheet Adjustment
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/About_spatial_adjustment_rubbersheetin...


The help document also says:

'When features are adjusted in a feature adjustment, an adjustment buffer of 50 meters, or 164.04 feet, is applied to surrounding features outside the adjustment area'

Is this buffer created from the vectors above, or parcels affected?

Any direction on where finding more data on this topic would be very-much appreciated.

Thanks, -Travis

[TiffanyPuett]

Hi Travis,

I will have to check in on the adjustment buffer. We have heard some concerns on data that wasn't coincident with parcels and shouldn't be furthermore. In testing, we didn't see any weird behavior where unintended vertices were moved however.

To answer your first question, the vectors they are talking about are not like vector data but more like actual vectors that you would learn about in math and science school. They have a "bearing and magnitude"--that is, a direction and a distance. That said, when you build your fabric and associate other layers to it, the data gets time stamped. Whenever you do a parcel edit and move a vertex, that vertex has a displacement vector associated with it (storing the bearing and distance). So that distance and direction is applied to the associated vertex in the associated feature class.