1. CS 321: Human-Computer Interaction Design
October 27, 2015
Data Entry, Storage, & Retrieval
Auto-Correct
File Systems
Associative Retrieval
Chapters 15, 17-18

2. Two models for entering data into a software system...
Data Entry
Two models for entering data into a software system...
Data Integrity
Users will enter garbage
Reject garbage immediately
Don’t let it taint the system
Data Immunity
Users might enter garbage
Try to work around errors
Seek user clarification
CS 321
October 27, 2015
Data Entry, Storage & Retrieval
Page 211

3. Is it better to edit or to audit?
Auto-Correct
Should software automatically correct perceived mistakes by the user, or merely notify the user?
Is it better to edit or to audit?
CS 321
October 27, 2015
Data Entry, Storage & Retrieval
Page 212

4. Data Storage
Consider two mental models for the operation of saving an altered file:
The Computer Novice
The Experienced User
Wouldn’t be altering the file if the results weren’t meant to be preserved
Envisions all alterations as permanent anyway
Knows that the version being altered is not the original stored version
Envisions all alterations as temporary until an actual save is performed
CS 321
October 27, 2015
Data Entry, Storage & Retrieval
Page 213

5. File System Implementation Model
Modern file systems have not been implemented to be transparent.
Confusing Features:
Relocating Files
Renaming files
Closing files
Saving changes
Discarding changes
Creating new files
Deleting old files
Opening existing files
Copying files
To varying degrees, users must be aware of what’s going on inside the system in order to effectively perform these operations.
CS 321
October 27, 2015
Data Entry, Storage & Retrieval
Page 214

6. An Alternative Represented Model
Cooper, Reimann, and Cronin suggest a different model, closer to the user’s mental model than to the implementation model.
Alter the name or location of the file
Create a copy to be preserved while the original is being altered
Create a copy of a significant version of the altered file
Activate one of the previously preserved versions of the file
Discard all alterations since the session began
CS 321
October 27, 2015
Data Entry, Storage & Retrieval
Page 215

7. Primary Data Retrieval Methods
Identity Retrieval
Find files based upon their names
Positional Retrieval
Find files based upon their locations within the storage structure
Associative Retrieval
Find files based upon some inherent attribute (e.g., type, size, date)
Identity and positional methods are convenient for data storage (i.e., the developer’s implemented model) and not for data retrieval (i.e., the user’s mental model).
CS 321
October 27, 2015
Data Entry, Storage & Retrieval
Page 216

8. Associative Retrieval Example
Automatically indexes and cross-references documents, s, attachments, spreadsheets, presentations, PDFs, etc., including compressed files, network drives, and Web pages
CS 321
October 27, 2015
Data Entry, Storage & Retrieval
Page 217