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Crosswalks, Translations, and Examples

Section 5 of the On-line Course:

Learning the Cadastral Data Content Standard


Section 5 describes practical uses of the Standard, and includes examples and exercises for two ways of using the Standard: Crosswalks, and Translations.


Topics in Section 5:


Logical Groupings in the Model

The Cadastral Data Content Standard's many entities and attributes may be organized into generalized groups of entities, which is useful for a basic understanding of the model. One way of grouping the entities is represented in the diagram below. Clicking on each box in the diagram will bring up a more detailed illustration of the entities in each group.

logical groupingsimage map

Organizations or individuals who might build a cadastral database which contains just a portion of the entire set of entities in the Standard, for example a database containing only Parcel information, can refer to this generalized grouping of the model to see how their data would fit in with the rest of the Standard. This also shows that no particular subject area exists in a vacuum ---  for example, a given database contains only Parcel information, it can be seen that the database still relates to other information such as Legal Area Description, Agent, and Boundary.

Compare the above illustration with the Standard's entity-relationship diagram. Note the many entities and attributes in each of the above illustrated groups. For example, look at the general category, Legal Area Description, above, and then look at the Standard's E-R diagram under Legal Area Description. Under Legal Area Description you will find details for survey system, PLSS information, and Outer Continental Shelf. Comparing each of the general categories pictured above with the Standard E-R diagram will bring about a more complete familiarity and understanding of the Cadastral Data Content Standard. The diagram above summarizes the more detailed Standard entity-relationship diagram.


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Crosswalk Exercise

Note: when working through this exercise, keep in mind that crosswalks are detailed comparisons between sets of information, which entail regularly referring back and forth between several lists of definitions and models. As such, crosswalks require time, focus, and patience. While this might sound like tedious work, it is not meant to dissuade you from following through with this exercise, because the good news is that when you take the time to do this exercise and learn from it, you will become very well prepared to crosswalk your own data to the Standard.

One of the main uses of the Cadastral Data Content Standard involves determining which parts of your database correspond to the Standard. This is done by "crosswalking" the entities in the Standard's logical model with the entities in your own database.

The purpose of a crosswalk is to express the user's data connotations and relationships in terms of the Standard's definitions and relationships. By doing this, discussions about various users' data can be facilitated through the use of a standard set of definitions. As mentioned in Section 1, communication is improved through the ability to correlate different data sets.

Generally, when conducting a crosswalk, you need to use:

To conduct a crosswalk, compare each entity and attribute, and their definitions, in your database with entity and attribute definitions in the Cadastral Data Content Standard until you find the entity or attribute in the Standard which matches your database. Note that there may be entities in your data which do not match with any entities in the Standard. Likewise, there may be entities in the Standard which your database does not contain. Furthermore, one or more of the entities in your data may crosswalk to the same entity in the Standard.

The crosswalk exercise will give you some practice.


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Translation Exercises

Translating data is the process of bringing existing data into compliance with the Standard. Usually done after a crosswalk, translation puts data into the format to comply with the Cadastral Data Content Standard. By translating data to the Standard, data can be more easily shared and effectively disseminated, which is one of the benefits of using the Standard described in Section 1.

The following exercises will give you some practice with the preliminary stages of matching actual cadastral data with entities and attributes in the Standard.

Note that Translations, like Crosswalks, require detailed reviews of entity and attribute definitions, along with the process of referring back and forth between various documents. The best way to approach the exercises below is to choose one of them, and work through it slowly.

Translate Columbia County, Wisconsin parcel layer information to the Standard. This excercise asks you to match parcel information descriptions with entities in the Standard.

Translate Yuma, Arizona land descriptions to the Standard. The two Yuma exercises entail matching land description information (such as SW4 SW4 SE4 SEC 6 10 23) with entities in the Standard.

Translate a Special Warranty Deed to the Standard. This exercise asks you to match information in a warranty deed with entities in the Standard.


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Real World Examples

The links below will take you to some basic discussions about work related to the Standard being done in Illinois, Kansas, and Washington. These each represent groundbreaking uses of the Standard. When you read about these examples, consider how they might relate to your own use of cadastral data.

Adams County, Illinois - a description of a highway department implementation of the Standard.

Osage County, Kansas - a cooperative effort to develop parcel coverage of urban areas.

State of Washington - a first step toward implementing the Standard.

As more organizations begin making use of the Standard in their physical databases, we will add their examples, whenever available, to this section.


Users and the Standard

The purpose of this section is to illustrate the ways in which specific users may typically implement the Standard, including the entities and attributes which they are most likely to use, and the ones they might not use. The examples below show illustrations of the Standard's entities which certain professions and/or applications might use.

PLSS Section Corner Recovery

GPS - Counties Getting Control Data

National Mapping - Plotting - Planning Map

Adjudicator - Use Authorization

County Recorder

Appraiser


This ends Course Section 5. Use the links below to return to the top of this page, or to go on to Section 6, or any of the other Sections or Modules.


Links to the Course Sections and Modules: [Quick Reference] [Introduction] [Section 1: Purpose and Benefits of the Cadastral Data Content Standard] [Section 2: How the Standard Was Developed] [Section 3: Other Standards and Related Activities] [Section 4: Data Modeling Techniques, Rules and Diagram Conventions] [Section 5: Crosswalks, Translations, and Examples] [Section 6: Understanding Compliance with the Standard] [Section 7: Maintenance of the Standard] [Section 8: User and Technical Support] [County Recorder Module] [GIS Specialist Module] [Surveyor Module] [Glossary]


Learning the Cadastral Data Content Standard

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Presented by the United States Department of the Interior Bureau of Land Management, and

the Federal Geographic Data Committee Cadastral Subcommittee