GSEQ for Windows: New Software for the Sequential Analysis of Behavioral Data, with an Interface to The Observer

Transcription

1 GSEQ for Windows: New Software for the Sequential Analysis of Behavioral Data, with an Interface to The Observer Vicenç Quera Dept. of Behavioral Science Methods University of Barcelona, Spain Roger Bakeman Dept. of Psychology Georgia State University, USA Measuring Behavior 2000, 3 rd International Conference on Methods and Techniques in Behavioral Research. Nijmegen, The Netherlands. GSEQ is a general-purpose program that analyzes behavioral sequences. It reads sequential data written in SDIS (Sequential Data Interchange Standard) format, and provides a variety of sequential statistics, including tables of lag frequencies, chisquares, and adjusted residuals, and also descriptive statistics like rates and average durations. Several kinds of data modifications are possible, including recoding, lumping, chaining, and time-windowing. GSEQ can also export results for further analyses using standard packages like SPSS. The program is useful for exploring both lagged associations in event sequences, and synchronic associations in time-based ones, and, generally speaking, for calculating sequential association statistics that reflect or characterize interaction processes in dyads or groups. The first versions of the software ran under DOS, and were published and presented elsewhere (Bakeman & Quera, 1992, 1995; Quera & Bakeman, 1998, 2000). GSEQ for Windows (GSW), a new version running under Windows 95 or later is presented. Like previous versions, it includes a utility for composing commands that request specific analyses, and a function for plotting the data in time x behavior plots. A new utility for analyzing agreement between observers and for calculating kappa is also included. GSW compiles and reads data files written in the SDIS language, whose syntax has been updated and improved. GSW is multilingual English/Spanish/Italian, and provides results in HTML format if requested. OTS, a utility external to GSW, which converts The Observer 3.0 and 4.0 ODF- to SDIS-formatted data is also presented (see Bakeman & Quera, 2000). The OTS program is useful for investigators who use The Observer (Noldus, Trienes, Hendriksen, Jansen, & Jansen, 2000) to collect data but who then wish to take advantage of the extensive data modification and analytic capabilities of GSEQ. Web sites:

2 GSEQ for Windows 2 A standard Windows interface: GSW has a typical Windows 95/98 user interface, i.e., a main menu with submenus, and several icon buttons pointing to the most commonly used functions. Opening and saving files, and copying, cutting, and pasting text are standard. Entering and compiling data: Data must be entered following SDIS language conventions. Once data are entered, they must be compiled into an MDS file, or just verified for syntactical correctness. Alternatively, data can be recorded by means of data collection software such as The Observer and ObsWin32. In the former case, the OTS program can convert The Observer data into SDIS files; in the latter, data are saved as SDIS files by default.

3 GSEQ for Windows 3 Overview of the Sequential Data Interchange Standard: All data to be analyzed must be entered in a single file. Data type must be declared at the outset. Depending on the data type, either codes, codes plus times, or intervals are permitted. Data types are: Event Sequences, State Sequences, Timed Event Sequences, Interval Sequences, and Multievent Sequences. Codes usually represent behaviors, but can also be used for representing contextual variables, behavior modifiers, individuals present, and so on. Units of analysis can be dyads, families, groups, or simply individuals. Data for a unit may consist of one or several observation sessions. Design, or independent, variables can be declared at the outset, and units be assigned to a combination of their conditions.

4 GSEQ for Windows 4 Checking compilation errors: When the compiler finds errors in the data, errors can be easily spotted and fixed by clicking on an error messages window. Log files: The compiler can save a log file containing a list of the errors found, or a summary of the data if the compilation succeeded.

5 GSEQ for Windows 5 Plotting data files: Once data are compiled, time event plots can be requested for them. All the codes defined in the data, or a subset of them, can be plotted against time. Output: Plots are useful for detecting possible sequential and synchronicity patterns by visual inspection, which should then be tested using sequential analysis.

6 GSEQ for Windows 6 Composing analysis commands: In order to run sequential or descriptive analyses of the data, or to modify them and create new codes, first a command file must be composed. Commands are composed by selecting them from the left pane. Command specifications are then shown on the upper middle pane. Codes, sets, or variables to which the command may be applied are shown on the right pane. Upon selecting the command and its specifications, it is composed and displayed on the lower middle pane, which can be edited manually if desired. The first command identifies the data file to be analyzed. Subsequent commands must be composed following specific conventions, which are enforced by the command composer. In this example, commands for a descriptive analysis are being composed: Sessions for all units will be pooled over. Also, all units sharing the same variable conditions will be pooled over. Descriptive, or Simple, statistics include frequencies, durations, average durations, average onset-to-onset durations, and so on.

7 GSEQ for Windows 7 Requesting analyses and exporting results: This figure shows a command file completed. Simple, or descriptive, statistics requested were frequencies, rates, probabilities (proportion of time codes are present), total durations, average and minimum durations, and average and minimum gaps (offset-to-onset durations). Some of those statistics were then requested to be exported (Send command) to a file, which can be read and analyzed further with standard statistical packages such as SPSS. Sequential statistics (Stats command) requested were joint observed frequencies, adjusted residuals, chi-square, and phi. A lag zero contingency table was then defined, with mother codes (MPas, MAct, and MRed) as Target, and infant codes (IQui, IAct, and IFus) as Given. Code & is a residual code, which makes both target and given lists temporally exhaustive. Adjusted residuals were then requested to be Exported to a file, to be analyzed further by some statistical program. Several exportation formats are available. Resulting files can be read by Excel, SPSS, StatGraphics, etc.

8 GSEQ for Windows 8 Running commands and selecting output format and appearance: Upon completing the commands, a dialog permits selecting several options: Commands are run by clicking on Run and then selecting the output format:

9 GSEQ for Windows 9 SIMPLE results (HTML): If HTML output is selected, results are displayed on an HTML viewer with frames. The upper section contains the requested statistics; the lower section contains hyperlinks pointing to specific tables in the upper section. In this example a table of Simple statistics is shown. A variable, mother's previous Experience with children, was defined in the data, with two conditions, Yes and No. For this particular analysis, the user requested that all dyads for which the Experience condition was identical were pooled over, resulting in two Simple tables, one for Yes, another for No. By default, RATEs are expressed in number of occurrences per 60 time units. E.g., rate for code MPas was per minute. PROBs indicate the proportion of total time for each code. E.g., MPas occurred 14.71% of the time. A total PROB greater than 1.0 indicates that codes overlapped each other.

10 GSEQ for Windows 10 SIMPLE results (ASCII): If ASCII output is selected, results are displayed on an standard ASCII viewer and editor window. A lower window is added showing hyperlinks to specific tables in the upper section. HTML output files: Can be printed directly from GSW's HTML viewer. Can be browsed and printed using any web browser. Can be read by Microsoft Word as HTML, converted into DOC format, and pasted to any document. ASCII output files: Can be browsed and printed using any text editor. Can be read by Microsoft Word as text, converted into DOC format, and pasted to any document. Tables will look better when Courier is used.

11 GSEQ for Windows 11 Sequential analysis results: In this example, a lag 0 table was requested. Observed lag frequencies are shown on the left: As data is Timed event sequential, tallies are time units (seconds). E.g., codes IQui and MPas co-occurred for 133 seconds out of a total of 3,099 seconds. Dyads with Experience = No are pooled over in this table. Adjusted residuals and Chi-square are shown on the right: Chi-square indicates that there is a significant lag 0 global association between mother and infant behaviors. In other words, mother and infant behaviors show some degree of synchronicity. Adjusted residuals are distributed as normal z scores, and indicate which mother and infant behaviors tend to co-occur more and less than expected (if there were no association). E.g., IAct and MRed tend to co-occur significantly more than expected (19.64), while IQui and MRed tend to co-occur significantly less than expected (-8.21). In order to compute chi-squares and adjusted residuals, GSW first computes expected frequencies under the null hypothesis of no association. Expected frequencies are computed differently depending on the data type, whether structural zeros exist in the table, etc. In this example, as column sums are unevenly distributed, some adjusted residuals might not be normally distributed.

12 GSEQ for Windows 12 Exporting results: SIMPLE statistics can be exported using the SEND command. Several formats for the exported file can be selected. Results are exported according to the POOL specifications requested by user (PR = PROB; AD= AVGD; etc). Sequential analysis results can be exported using the EXPORT command. In this example, adjusted residuals for every cell in a 4x4 table are exported for each unit (or dyad):

13 GSEQ for Windows 13 Modifying the data: New codes can be defined from existing ones using data modification commands: Modified data are then saved for further analyses:

14 GSEQ for Windows 14 Modifying the data: Once modified, data can be analyzed or plotted, and new codes can be used exactly as the original ones. For example, And Act = MAct IAct; defines new code Act and assigns it to every time unit where codes MAct and IAct ocurred simultaneously. Command Or NoIAct = IQui IFus; defines new code NoIAct and assigns it to every time unit where either code IQui, or code IFus, of both occurred. This plot of the modified data shows original plus new codes. Blue indicates how code Act is created, Red indicates how code NoIAct is.

15 GSEQ for Windows 15 GSW tools: Cohen's kappa and agreement plots can be obtained for assessing agreement between observers when data for each observer is saved on a different file. Structure of an MDS file can be inspected by means of the Show MDS tool.

16 GSEQ for Windows 16 Converting The Observer data to SDIS-formatted data: The OTS program OTS is a utility external to GSEQ for Windows. To convert a collection of The Observer 3.0 or 4.0 data files to one single SDIS file, or to separate SDIS files, first a The Observer project file is open. ODF (Observer Data Files) defined in the project can then be selected from the left pane for conversion. OTS options control how SDIS has to define codes, and how The Observer modifiers must be translated. If more than one ODF file is selected for conversion, user can choose to merge all the converted files into a single SDIS file.

17 GSEQ for Windows 17 Converting The Observer data to SDIS-formatted data: The OTS program Three ODF files (The Observer 3.0) with a common project file: PLAY.CNF :00:00.00 {media} D:\video\child011.mpg {indvar} {start} 0.0 look,girls 40.3 noplay 42.6 look,mix noplay solit,puzzle noplay assoc,toys look,mix assoc,toys,girls solit,toys {end} {notes} PLAY.CNF :00:00.00 {media} D:\video\child012.mpg {indvar} {start} 0.0 noplay 65.1 coop,toys,boy look,boy coop,toys,boy noplay paral,puzzle,boys look,mix paral,puzzle,mix noplay {end} {notes} PLAY.CNF :00:00.00 {media} D:\video\child013.mpg {indvar} {start} 0.0 look 66.7 solit,blocks noplay paral,blocks,mix noplay look,girl solit,blocks look,girl noplay solit,blocks noplay solit,blocks look,girl {end} {notes} OTS converted them into this single SDIS file, and created separate codes for behaviors and their modifiers (using codes defined in The Observer CNF file):

18 GSEQ for Windows 18 References: Bakeman, R., & Quera, V. (1992). SDIS: A sequential data interchange standard. Behavior Research Methods, Instruments, and Computers, 24, Bakeman, R., & Quera, V. (1995). Analyzing interaction: Sequential analysis with SDIS and GSEQ. New York: Cambridge University Press. Bakeman, R., & Quera, V. (2000). OTS: A program for converting Noldus Observer data files to SDIS files. Behavior Research Methods, Instruments, and Computers, 32 (1), Noldus, L.P.J.J., Trienes, R.J.H., Hendriksen, A.H.M., Jansen, H., & Jansen, R.G. (2000). The Observer Video-Pro: New software for the collection, management, and presentation of time-structured data from videotapes and digital media files. Behavior Research Methods, Instruments, and Computers, 32 (1), Quera, V., & Bakeman, R. (1998). SDIS-GSEQ 2.0: Software for the analysis of behavior sequences. Measuring Behavior 98, 2nd International Conference on Methods and Techniques in Behavioral Research, Groningen, The Netherlands. Quera, V., & Bakeman, R. (2000). Quantification strategies in behavioral observation research. In T. Thompson, D. Felce, & F. Symons (Eds.), Behavioral observation: Technology and applications in developmental disabilities (pp ). Baltimore: Brookes Publishing.