Guttman Scaling

l Also known as –Scalogram analysis –Cumulative scaling l Purpose: –Establish a one-dimensional continuum –Perfectly predict item responses from total score –Seldom perfect in practice

Guttman Scaling Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Start with a large set of items that you think all reflect the same construct. Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4 Work quickly and effectively under pressure 49 Organize the work when directions are not specific. 39 Decide how to manage multiple tasks. 20 Manage resources effectively. 4

Guttman Scaling Have many judges rate each statement with respect to whether it is favorable with respect to the construct -- a yes/no rating. 3Scan a multitude of information and decide what is important. 1Manage time effectively 2Manage resources effectively. 3Scan a multitude of information and decide what is important. 4Decide how to manage multiple tasks. 5Organize the work when directions are not specific. 1Manage time effectively Rating Sheet YesNo

Guttman Scaling Lay out a table:

Guttman Scaling Lay out a table: ItemItemItemItemItemItem Respondent YYYYYY 15YYY--Y-- 3YYYY YYYY YYY YY--Y YY YY Y----Y

Guttman Scaling Lay out a table: ItemItemItemItemItemItem Respondent YYYYYY 15YYY--Y-- 3YYYY YYYY YYY YY--Y YY YY Y----Y When sorted by row and column it will show whether there is a cumulative scale.

Guttman Scaling Lay out a table: ItemItemItemItemItemItem Respondent YYYYYY 15YYY--Y-- 3YYYY YYYY YYY YY--Y YY YY Y----Y When sorted by row and column it will show whether there is a cumulative scale. Note the exceptions.

Guttman Scaling l There are several statistical techniques for examining the table to find a cumulative scale. l Because there is seldom a perfectly cumulative scale, we usually have to test how good it is. l These statistics also estimate a scale score value for each item.

How Does Respondent Use? l For selected items (the final scale), they simply answer whether they agree or not (yes/no). l Since each item has a scale value, we can add these values. l Total score is the sum of the scale items respondent agreed to.