Introduction. This is a sample HTML page for the input and display of valuation data. The immediate goal of this presentation is to allow you to easily see what "names" have been assigned by the Data Consortium to each individual item of information that comprises a commercial property's economic valuation, including each of the items comprising the assumptions made for that valuation. Mousing over the labels or values for the fields on this form, you can easily see what is assigned to the 'dc:names' attribute associated with the HTML element (e.g., an <input>, <select>, or <span> element). The 'dc:names' attribute contains one or more Data Consortium -defined names for the value of the input field, names which are recorded in the Data Consortium Dictionary (DCD). These names are the same names used in a scriptable object model hosted by the Data Consortium Toolkit.
Objectives. This form is intended to serve several other purposes beyond being just a handy reference for Data Consortium-defined names. First, Argus, a popular property valuation system, is the basis for many of the information items below, so this set of names must be validated as adequate for supporting interfaces to that system. Second, because For-Sale Property Listings are merely owner valuations (albeit decorated with brokerage contact and other information) this set of names sets the stage for automated property searches based on value (in addition to the usual parameters of price, location, and available facilities). Third, because For-Rent Property Listings can be viewed as just a proposed lease, a valuation datastream's rent roll, which details the characteristics of leases associated with a property, plays a central role in developing their information schema. Fourth, because Investment Performance data contains a chart of accounts similar to that forecast by a property valuation, the set of names below assigned to components of Net Operating Income need to be validated against the schema(s) developed by industry organizations such as NCREIF and MISMO, to whom (or to whose stakeholders) quarterly and annual operating figures for the property are submitted.
Data Model. A Property may have one or more Valuations associated with it. Valuations are a subtype of the DCD's Topic category, so its attributes are, by convention, interpretable to be attributes that apply to the Property itself. Valuations contain one or more forecasted values and indices, forecasted ChartOfAccounts, and forecasted RentRoll. Valuations also contain a set of assumptions used to drive its calculations, including certain estimated values (e.g., discount and growth values), an estimated Chart Of Account, and an estimated RentRoll. Valuations also include specification of Management Policies that relate to lease commissions, rent escalations and abatements, and others; these management policies are then associated with specific leases within the estimated rent roll. Both policies and policy exceptions can be specified; policy exceptions are policies that reference the policy to which it is an exception. A Policy identifies business rules that govern, for instance, how rent increases are to be caculated.
Identifiers. Identifiers can be assigned to and referenced between a real property, one or more valuations, a rent roll, and multiple types of management policies. Universal Resource Identifiers (URIs) are the mechanism used for all identifiers, as these are the base mechanism for representation of Universal Resource Names (URNs). It is recommended that the URL portion of a URI use the names of topics as a prefix, e.g., http://policies.dataconsortium.org. At this handle for instance, the Data Consortium provides entry points for services connected with management policies, including reference XML elements for default/common policies. Similarly, a particular lease identified as Lease12345 would have URI http://leases.yourSite.com#Lease12345. For Data Consortium members, address http://atlas.dataconsortium.org contains identifiers and information for major urban and political locations; http://markets.dataconsortium.org provides market leasing information useful as sets of assumptions during a valuation. Membership in the Data Consortium has its advantages.
Buttons. The buttons on this HTML page serve various functions. First, "Add/New" buttons are placed so as to identify when information can be entered multiple times for a category. For example, a Lease is allowed to specify one or more spaces in a facility that are the subject of the lease; this form can therefore be used to represent a lease that simultaneously covers multiple units and storage facilities within a building. Second, some buttons initiate calculation of a valuation; until that time, the "valuation" information would presumably not be shown, showing instead just the assumptions input fields.
Relationship to XML Tags. Each part of the "name" assigned to an information item represents an XML element. Example: the name assigned to the first "Property Address" field below is "Site.Address.AddressLine.1.text". In an XML-encoded file, either <Site.Address.AddressLine.1.text value="foo"/> OR <Site.Address.AddressLine.1.text>foo</Site.Address.AddressLine.1.text> would be used to tag the text. The nested-element equivalent for this is <Site><Address><AddressLine><text>foo</text></AddressLine></Address></Site> and its encoding in DCN elements would be an <Entry xsi:type='Memo' dc:names='AddressLine.1'><text>foo</text></Entry> element within a "memos" <list> element for the Site.
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12/18/01 Working Draft.