1. Data Collection (Continued) Lecture Notes for September 1 SPEC 3020 Fall 2009 http://coefaculty.valdosta.edu/pgunter/SPEC3020/index.htm

2. Accuracy of Recording Systems Frequency is most Accurate Interval recording is next most accurate Time sampling is the least exact

3. Interval Recording Partial Interval Recording – the behavior does not consume the entire interval Whole Interval Recording – the behavior consumes the entire interval

4. Continuous vs. Non-continuous intervals Recording several behaviors Recording behaviors of several students

5. Time Sample The student is observed only at the end of the interval As the interval gets longer, the similarity between the data recorded and the actual occurrence of the behavior probably decreases.

6. Important Points and Differences Concerning Interval Recording and Time Sampling Both provide an approximation. Neither is as accurate as event recording. Interval recording provides a closer approximation to actual occurrence Interval recording is usually used for a short observation and time sampling for longer periods Time sampling is easier to manage while teaching. Occurrence is noted and recorded at any time during interval recording and only at the end of the interval when using time sampling. Observers report the number of intervals, not the number of behaviors.

7. Reliability Gross 5/5 100% Occurrence only reliability 3/6 50% (when target occurs in less than 75% of intervals) Non Occurrence reliability 4/7 57% (when target behavior occurs in more than 75% of the intervals) XXXXX XXXX Observer 1 Observer 2

8. Factors Affecting Data Collection and Reliability Reactivity – Something new has been introduced Observer drift –tendency to change stringency of operational definition Complexity – the more complex the system the more reliability is in jeopardy. Expectancy – Preconceived notions

9. Continuous recording systems http://www.youtube.com/watch?v=bozysY7c G3M

10. Write an operational definition for a behavior of your choice and describe the data collection system you will use to gather data related to the behavior.