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CodeThis! software was developed to support implementation of the Generalized Frequency Coding (GFC) method (Smith and Gutberlet, 2001). Please see the article and http://journalsonline.tandf.co.uk/openurl.asp?genre=article&id=doi:10.1080/10635150121392 for information about GFC:
CodeThis! runs in Microsoft Excel 97 for the PC and Microsoft Excel 98 for the Macintosh. To download CodeThis! click on “Software” at the top of the page.
CodeThis! will transform raw data from polymorphic characters into frequency codes according to the methodology of GFC. Characters will be divided into subcharacters, and weights for each subcharacter will be assigned. The codes and weights can then be entered into other software (e.g., PAUP*) for phylogenetic analysis.
A startup sheet (Fig. 1) allows you to enter the name of the character you are coding along with the number of taxa and number of specimens examined per taxon. If sample sizes are unequal, enter the largest number of specimens examined in a single taxon. Clicking on the button then creates a raw data entry form (Fig. 2). The original spreadsheet remains intact as a template for new data entry forms that will be used for additional characters.
The raw data entry form reports the following descriptive statistics for each taxon as you enter the character data: number of specimens (n), minimum value, maximum value, mean, variance, and standard deviation (Fig. 2).
After you have entered all of the data for a particular character, click on the button “Calculate Codes” on the raw data entry form. Then use the tabs at the bottom of the form to navigate among different types of information. For example, cumulative frequency codes and subcharacter weights will be shown when you click on the tab “CumCodes” (Fig. 3).
Suggestion: For characters describing the condition of paired features that can vary within individuals, you may wish to enter the number of specimens x 2 so that you will have space to record two pieces of data per specimen.
| Fig. 1.—CodeThis! startup sheet. |
| Fig. 2.—CodeThis! raw data entry form. In this hypothetical example for the character number of canthal scales, the numbers 1–4 above the first four columns refer to specimens. The numbers entered into the boxes in these columns are the canthal scale counts for these specimens. All of the other information on the raw data entry form is calculated by the software. To calculate frequencies, cumulative frequencies, frequency codes, cumulative frequency codes, and subcharacter weights, click on the button “Calculate Codes.” Then navigate among this information by clicking on the tabs at the bottom of this raw data entry form (Raw Data, Frequency, Cumulative, FreqCodes, and CumCodes). |
| Fig. 3.—The screen shown here was obtained by clicking on the button “Calculate Codes” and then the tab “CumCodes” on the raw data entry form shown in Fig. 2. The letters under 4 and 5 represent frequency bins; thus, for example, 100% of the L. lamellae (****new name??****) specimens had greater than 4 canthal scales, and 0% of the L. ichthyus (****new name??****) specimens had greater than 5 canthal scales. Both subcharacters are potentially informative and weights have been assigned. Unequal subcharacter weighting (USW) and equal subcharacter weighting (ESW) are discussed in Smith and Gutberlet (2001). |
