CCs details

You've seen that Lertap analyses start with the creation of two Excel worksheets: Data and CCs.

 

The CCs worksheet contains the all-important lines of Lertap syntax which effectively control how Lertap and Excel analyse the data found in the Data worksheet.

 

CCs really stands for Control Cards.  It used to be the case that data analysis was based on the use of punch cards.  Years back, a typical data analysis job involved the use of a keypunch machine -- data were punched on cards, as were the instructions which told the computer how to analyse the data.  The first versions of Lertap were based on the use of punch cards, and the term "control cards" has been carried into most subsequent versions.

 

You'll see that we sometimes refer to the rows in the CCs worksheet as "lines", and sometimes as "cards".  We use these terms interchangeably; they mean the same thing.

 

There are a total of eight "cards" which may be used in a CCs worksheet.  The number of cards used in any given job depends on two main factors: the type of subtests being processed, and the complexity of the item scoring desired.

 

We'll spell out the general nature of all of the cards below.  The topics immediately following provide more exact details on the syntax of each card.

 

*col

The basic Lertap control card, used and required by all subtests, cognitive and affective.  Each time Lertap sees a *col card in the CCs worksheet, it thinks "Ah-ha, here comes a new subtest", and it expects the user to then indicate the columns in the Data worksheet which are to be processed.  (Click here to read about a problem which can arise with very long *col lines.)

*sub

This card is optional for cognitive subtests, but required for affective subtests.  *sub cards are used to convey particular subtest characteristics to Lertap, such as the name and title of the subtest, and the number and nature of the response codes used by the items belonging to the subtest.

*key

Gives the right answer for the items of a cognitive subtest.  This card is always required for cognitive subtests, but it's not used at all with affective subtests.

*pol

"pol" stands for polarity, that is, for plus (+) or minus (-). Not used by cognitive subtests, and optional for affective subtests.  When used, it defines the type of scoring to be applied to affective items: plus (+) for forward, and minus (-) for reverse.

*alt

An optional card for both cognitive and affective subtests.  When used, it indicates the last response code used by each item.  If this card is not used, it is assumed each item uses the same number of response codes.  (The format of this card changed early in 2005: please refer to Example C7 under the Cognitive CCs topic for details.)

*wts

An optional card for cognitive subtests; not used by affective subtests.  This card makes it possible to quickly tell Lertap that the items of a cognitive subtest have different "weights", that is, the right answers to the items have differing point values (the first question might be worth one point, for example, while other questions might be worth more points).  This card is also known as the *wgs card.

*mws

An optional card for both cognitive and affective subtests.  "mws" stands for multiple-weights specification.  This is the most powerful control card of all -- it allows any weight to be applied to any item response.

*exc

An optional card for both cognitive and affective subtests.  "exc" stands for exclude.  This card is used to quickly remove items from a subtest.  (*exc is not mentioned in the manual.)

*tst

This is a very special control card.  It can only be used once in any CCs worksheet, and, when used, it has to be the very first card.  It's used to get Lertap to make a copy of the data set, with only certain data records to be copied to the new data set's Data worksheet.  *tst is used to set up a new Lertap workbook containing a subset of the original Data records (for example, just the males, or only those in a specified School District).

 

This has been a quick introduction to Lertap's control "cards".  We'll go on now to provide more specifics, and we'll do this by subtest type, cognitive first, then affective.