Free Operant Observation

Free Operant Observations are appropriate for all children, and are simple to do regularly in a classroom setting if an observation can be scheduled during a time when a child has the opportunity to choose from among many different, possibly reinforcing, items or activities (e.g., free play). These are appropriate assessments for children who engage in challenging behavior when preferred toys are taken away, because items are never removed after selection or engagement. When conducting a Free Operant Observation, the observer may discover highly-preferred actions or activities that are not typically thought of when brainstorming reinforcers, such as dancing to music, engaging in stereotypy, or escaping adult attention. Typically, Free Operant Observations are not conducted with edible items.

 Although Free Operant EBIP_Reinforcement_Preference Assessment_Free OperantObservations may not be as accurate at determining
preferences as MSWOs, MSWs, and Paired Stimulus Preference Assessments (i.e., trial-based assessments), these are appropriate for children who are unable to select between highly-preferred and low-preferred items. For example, if you conduct a Paired Stimulus Preference Assessment and noticed that the child always selects items from one side (i.e., side bias), a Free Operant Observation or Single Stimulus Preference Assessment should be conducted instead. Further, trial-based preference assessments require that the implementer have prior knowledge to which items are likely to be highly-preferred or low-preferred by the child. When an implementer is unfamiliar with the child, a Free Operant Observation would be an appropriate preliminary preference assessment, because a wide variety of items are simultaneously available and no prior knowledge of the child’s preferences is required. These assessments may not provide information about a wide variety of potential reinforcers if a child always interacts with only one item (e.g., chooses to play with one toy for the entire observation).

EBIP_preference assessment_free operant_4Free Operant Observations may be naturalistic or contrived. In a naturalistic Free Operant Observation, the child is permitted to engage freely in a typical, everyday environment. For example, a teacher may set aside 15 minutes to unobtrusively observe a new student in the free play area. In a contrived Free Operant Observation, the teacher intentionally sets up a predetermined number of items within sight and reach of the child. For example, for a non-ambulatory child, a teacher may to put a variety of items within the child’s reach prior to the session start. A contrived observation may also be helpful if some potentially reinforcing items (e.g., electronic tablet, water table) are not typically available.

For both types of observations, the teacher observes the child for a predetermined amount of time without interference. The items the child approaches consistently and engages with for the longest are considered the child’s highest preferred items, and the items that the child does not approach are considered the child’s lowest preferred items. It is important to (a) perform assessments regularly because preferences may change, and (b) regularly assess whether the child is able to scan two or more items on a surface, as MSWOs, MSWs, and Paired Stimulus Preference Assessments may be more accurate in determining preferences than Free Operant Observations.

Before beginning, you should collect the following materials:

Data collection sheet
Naturalistic environment (e.g., free play, resource room) or predetermined variety of items

Now you and your child are ready to begin.

1. Set up your contrived environment EBIP_Reinforcement_Preference-Assessment_Free-Operant-2or lead the child to the naturalistic environment. For example, you might bring a child into a resource room and tell her to play freely, or for a non-ambulatory child, you might set up a predetermined variety of items within her sight and reach.

2. Observe the child unobtrusively, and record the following on your data sheet during each trial:

  • Whether the child approaches an item (i.e., reaches out and takes it).
  • Whether the child engages with the item. For engaging with toys, this might include pushing buttons on the toy, swinging the toy around, or otherwise manipulating the toy. Engagement does not necessarily have to be manipulating the toy as it was intended, but should not include problem behavior (e.g., throwing the toy, breaking the toy).
  • The duration for which the child plays with the toy (i.e., the amount of time between the child’s approach and rejection of the toy). You may also record the child’s engagement in other activities. For example, you might record the duration of time a child engages in stereotypy, dances to music, or moves into spaces without other children. We don’t typically think of these when we are brainstorming reinforcers, but if these are highly-preferred by the child, they may serve to reinforce target behaviors. For example, a child might get a break from teacher interaction or be allowed to engage in stereotypy contingent on responding.

You may also record the child’s engagement in other activities. For example, you might record the duration of time a child engages in stereotypy, dances to music, or moves into spaces without other children. We don’t typically think of these when we are brainstorming reinforcers, but if these are highly-preferred by the child, they may serve to reinforce target behaviors. For example, a child might get a break from teacher interaction or be allowed to engage in stereotypy contingent on responding.

3. Continue recording approaches, engagement, and duration of engagement with each item until you have completed the predetermined observation time period.

4. At the end of the session, record items that were within view and/or reach of the child that he or she did not approach. It will be useful for future trial-based Preference Assessments to identify items that may be low-preferred by the child.

Data Sheet:
Free Operant Observation: Data Sheet 

To cite this page (APA 6th edition):

  • Chazin, K.T. & Ledford, J.R. (2016). Free operant observation. In Evidence-based instructional practices for young children with autism and other disabilities. Retrieved from http://vkc.mc.vanderbilt.edu/ebip/free-operant