Compare the three schema designs in four categories: global and local declarations; nesting of elements; reusability; and interaction with namespaces.

What will be an ideal response?

Global and local declarations
Russian Doll: The schema contains one single global element; all other declarations are local.
Flat Catalog: All declarations are global.
Venetian Blind: The schema contains one single global element; all other declarations are local.

Nesting of elements
Russian Doll: Element declarations are nested within a single global element.
Flat Catalog: Element declarations are not nested.
Venetian Blind: Element declarations are nested within a single global element referencing named complex types, element groups, and attribute groups.

Reusability
Russian Doll: Element declarations can only be used once.
Flat Catalog: Element declarations can be reused throughout the schema.
Venetian Blind: Named complex types, element groups, and attribute groups can be reused throughout the schema.

Interaction with namespaces
Russian Doll: If a namespace is attached to the schema, only the root element needs to be qualified in the instance document.
Flat Catalog: If a namespace is attached to the schema, all elements need to be qualified in the instance document.
Venetian Blind: If a namespace is attached to the schema, only the root element needs to be qualified in the instance document.