http://spssx-discussion.165.s1.nabble.com/2-Variables-7-cases-10-observations-Simple-tp5735614p5735687.html
The raters (more than one for inter-rater reliability reasons) observed videos of children in a classroom setting for 50 minutes. Coding tracked defined anxiety behavior and defined hyperactivity behavior. The coders had coding sheets that had columns for Time (in seconds), AN and HA. They put a tally "1" in the variable column at the noted second if either of the behaviors was observed. So, for a given subject, the coding sheet had:
Time AN HA
00:00:00 1 1
00:00:01 1
00:00:02 1
...etc
The tallies of both variables were totaled. In addition to the individual observations, time was aggregated in 5 minute blocks. If the child left the observation session (doctor's appointment, nurse's office, whatever), the totals for a given 5 minute block ended up totaled as 0. Each 5 minute aggregate was labeled T1, T2, etc. Only 7 children agreed to participate. Don't get me started....
My first research question related to the the amount of anxiety and hyperactivity: Do highly anxious children exhibit a higher level of HA than low anxiety children? Originally, I thought to run frequencies/correlations on the second-by-second data for each student. Then I thought to run the 5 minute block aggregates. I found that my data to be non-normalized, and I decided that Pearson's r was not appropriate to determine the correlation between the two variables. I ran a scatter plot to determine monotonicity and found an adequate relationship. So, I ran Spearman and Kendall on the 5 minute blocks, then Somers (because of the IV/DV nature of the data). I found a strong positive correlation in each output. As the comments came back from the SPSSX Extremely! helpful responders, I understood that my data might be overstated and I ran the same procedures on the means. This yielded no significant correlation in either direction. (Poop! Technical term?)
Another research question related to the "causal" relationship between AN and HA. So, I coded any HA that followed withing 30 seconds of an AN observation (a theoretically defensible time frame) to indicate that for that pair of observations, HA followed from AN. This I ran as the total of AN against the total HA within 30 seconds of AN by student (of the total AN observed for each student, how many were followed within 30 seconds by HA?). Interestingly,I found a strong positive relationship between the variables.
That's the set up, in a nutshell.
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