PiscesLogoSmallerStill Creating a data file using a spreadsheet

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A data set is stored as a comma-delimited text file with the extension .csv or an Excel file (.xls). It is normal to initially organize your data in a spreadsheet such as Excel and then save the worksheet as a comma delimited (csv) file for use with Growth II.

 

There are different arrangements of data for the analysis of age classed and incremental data which will be described in turn below.

 

Age classed data

 

For simple size at age measurements, the data are organized as a simple 2-dimensional array as follows:

 

Example Excel G2

 

 

Your data for analysis should comprise observations of the age (time), length, standard deviation of length, weight and standard deviation of weight for organisms, which are organized into columns. The first row of each column holds the title that the program uses to know what type of data the column holds. You must use the following standard titles:

 

For age classed data:

 

Age identifies the column as holding the ages (time since birth) of the animals. Ages can be input as integer or real numbers. Age can either be the age of an individual animal or refer to an age class.

Length identifies the column as holding length at age data. These data can be either be measurements for individual animals or the mean for an age class.

Weight identifies the column as holding weight at age data. These data can be either be measurements for individual animals or the mean for an age class.

Length SD identifies the column as holding the standard deviations of length at age data. When age classed data are used this column gives a measure of the variation in length between the individuals in a single age class.

Weight SD identifies the column as holding the standard deviations of weight at age data. When age classed data are used this column gives a measure of the variation in weight between the individuals in a single age class.

 

The image below shows an example of data that includes lengths and weights and standard deviations. This data set, named bass.csv, is included with Growth II.

 

bass data in Excel

 

Incremental data

 

For incremental data the layout in in a spreadsheet is as follows. This data set, named incremental test Gompertz.csv, is included with Growth II.

 

 

example incremental data layout

 

 

Sample identifies the column as holding an identification number or name for the individual.

Size T0 identifies the column as holding length or weight of the individual when first measured.

Size T1 identifies the column as holding length or weight of the individual when measured on a second occasion.

Time Gap identifies the column as holding data on the time difference between the measurements at time T0 and T1.

Known Age for a growth curve to be fitted to incremental data it is necessary to know the size of at least one individual at a known age. Place in this column a known age as either a real or integer value.

Known Size place in this column the size of individuals of known age.