Exporting data for analysis

This page will briefly explain what the different type of export possibilites are and how to proceed with further analysis in R or SPSS. A few example scripts in R can be found on the statistics page of this documentation.

Export to Excel

Data can be exported to Excel on all platforms as an Excel file, with the data collected in 1 sheet. The format of the Excel file is identical to the Export to SPSS and R option, as described in the next section. The format follows the table as shown in the main interface, and collates all the cells vertically. Basic analysis can be done in Excel, however this is not recommended as there might be missing values in the data set. Missing values in Excel can result in incorrect behavior for certain functions and is therefor not recommended. Furthermore, the number of analyses available in Excel are also limited. For a proper analysis, use the Export to SPSS and R option described below.

Export to SPSS and R

With this option, data is exported in a tab-delimited format that is suitable for importing in SPSS and R. Data from every cell will be collated vertically, with unique identifiers on each row. When selecting this option, a dialog will ask which parameters you wish to export (Figure 1). By default the first four parameters are selected. This selection can be expanded to other parameters; if a parameter is selected but not present in the data set, it will be ignored. This export function can be used for analyses that involve the number of events, the duration of events or the intensity and classification of the data. Testing differences in fusion onset can be modeled statisitcally using survival analysis, and requires a different export format, as described in the next section. Performing statistical tests and analyzing the data is discussed in the statistics documentation.

Export dialog
Figure 1: The preference dialog, with panels for loading, plotting, detection and classification

Export for survival analysis

Data can be exported to a format suitable for survival analysis. This format is always a tab-delimited text file with the .dat extension. Depending on the level of processing performed in the interface before exporting, multiple co-variates will be exported besides the core parameters. The basis for survival analysis is briefly explained in the statistics documentation. The format will contain columns for different strategies for modeling the onset of events, called strata, and will include all possible co-variates that are present in the data set at the time of export.