Norman’s seven stages of action are meant to illustrate the mindset of individuals while in the process of performing a task. The stages themselves are:
I can show process in action through the example of unlocking a locked door. In this situation, a possible goal would be “To return back to my room after class”. The general acts required to achieve this goal would include walking back to my building, returning to my dorm room once inside the residence hall, and lastly entering. One possible intention to act that would follow from this is: “I need to unlock the door to my room”. The sequence of actions upon returning home would then have to include the act of unlocking my door in order to enter it; more specifically this would be “put my key in the lock, turn it and push the door open”. Finally, in order to accomplish the main objective here, I would need to reach my room and do all acts that have been previously described. These initial four stages summarize the “Gulf of Execution” according to Norman, which specifically seem to encapsulate all the steps of this process that are dependent on my actions, namely my abilities, my knowledge of the device of the door lock itself, my memory of the process of unlocking something etc. More specifically, because the Gulf of Execution can be summarized as the gap between the idea of doing an action and that act coming to fruition, it can also depend on how much visibility or how many affordances are present in the device itself. If performing the function expected of me is far more intuitive, with qualities that possess some kind of a visual clue to its overall purpose, then this gulf would probably shrink, while if it is far more dependent on prior knowledge, it would grow. In this case, the design of the door would likely depend on the visibility of the keyhole and the ease of turning once the key is, implying a somewhat small Gulf of Execution as only those two steps would be required. After this point, the remaining stages would depend more on the effects of the world/circumstance. Firstly, assuming that I am able to unlock the door, I would “perceive the state of the world”; in this case I would probably hear the sound of the door unlocking or see the key turn fully in the lock. After this, I would interpret what just happened, acknowledging that “the sound I just heard is associated with a door (un)locking”. Finally, the last step would be my evaluation that the door is now finally free to open, allowing me to push the door, enter and complete my initial objective. In the case of the final three steps, the Gulf of Evaluation (the ease of noting whether the purpose of the devise has been accomplished) would also be very small considering how unique and apparent the sound of a door unlocking is to the average person. Because the gap between execution and evaluation is roughly instantaneous, since you would hear the bolt pretty much immediately after turning the key, it would be very easy to know if the device’s function has been completed. As a result, I would definitely say the model is quite straightforward, with the process being fully described by the seven stages. CommentsThere are 2 key items in Norman’s The Psychology of Everyday Things that I specifically want to speak to;
Norman may not have adhered to the strictest definition of ‘affordance’ but his theory is profound and insightful in its simplicity. He basically ignores the concept that an affordance can be ‘invisible’ and stated that affordances must provide strong clues to the operation of things. Also, when affordances are taken advantage of, the user will know what to do just by looking. He extended his theory to state that the value of a well-designed object is that when it has such a rich set of affordances that users can do things with it that the designer never imagined. One of the most important principles in the design of a system is visibility. This really resonates with me! The first step in system design should be to understand the need for visible management of the system. Users rarely take the time to read instructions and businesses today do not have the time to pull out the users manual each time they start a task. It is the responsibility of the system designer to make the operation clear, project a good image of the operation and to take advantage of other things people might be expected to know. This process starts by providing a good conceptual model and making things visible. Because people form mental models thru experience, training and instruction the first step in the development process should be based on these mental models as you are forming the goal and forming the intention. This needs to be based on perceived actions and visible structure. Once this is complete, you can specify the action and execute the action. This should always be followed up with a transparent evaluation of the results. These are all steps defined by Norman in his seven stages of action: forming the goal, forming the intention, specifying an action, executing the action, perceiving the state of the world, interpreting the state of the world and evaluating the outcome. I once saw an excellent example of the seven stages of action. I was at a conference where they were polling the audience response to the speaker. The polling device was a dial that was clearly label ‘hate it’ on the low end and clockwise from there ‘love it’ on the high end. This simple mechanism allowed the participants to twist the dial as they listened to the speaker. The system captured the audience response as the speaker spoke. The results gave a very clear graph of how the audience was responding emotionally to the speaker. The dial was a simple visual tool that was easy to use and participants clearly put their likes and dislikes into the poll with a very simple and natural twist of the dial. Even with the best system design in the world, one item to keep in mind is the fact that these mental models need to be refreshed so they stay current. Evaluation must be an on-going process. I personally think the save button on computers is ridiculous. It is generally shaped like a ‘floppy disk’. No one under the age of 25 has ever seen a floppy disk. This visual image is not sustainable going forward and an alternative needs to be developed and deployed. Norman suggests that we use the 7 stages of action as a design aid. It can help simplify a system design if you review each stage of action and question the design along the way. To do this he offers advice in the design process; tell what actions are possible, determine mapping from intention to physical movement, perform the action, evaluate whether the system is in the desired state, determine mapping from the system state to interpretation, tell what state the system is in. Seven stages of action is a term coined by the usability consultant Donald Norman.
He explains this phrase in chapter two of his book The Design of Everyday Things, in the context of explaining the psychology of a person behind the task performed by him or her.
The history behind the action cycle starts from a conference in Italy attended by Donald Norman.
This excerpt has been taken from the book The Design of Everyday Things:
I am in Italy at a conference. I watch the next speaker attempt to thread a film onto a projector that he never used before. He puts the reel into place, then takes it off and reverses it. Another person comes to help. Jointly they thread the film through the projector and hold the free end, discussing how to put it on the takeup reel. Two more people come over to help and then another. The voices grow louder, in three languages: Italian, German and English. One person investigates the controls, manipulating each and announcing the result. Confusion mounts. I can no longer observe all that is happening. The conference organizer comes over. After a few moments he turns and faces the audience, who had been waiting patiently in the auditorium. "Ahem," he says, "is anybody expert in projectors?" Finally, fourteen minutes after the speaker had started to thread the film (and eight minutes after the scheduled start of the session) a blue-coated technician appears. He scowls, then promptly takes the entire film off the projector, rethreads it, and gets it working.[1]: 45–46 Norman pondered on the reasons that made something like threading of a projector difficult to do. To examine this, he wanted to know what happened when something implied nothing. In order to do that, he examined the structure of an action. So to get something done, a notion of what is wanted – the goal that is to be achieved, needs to be started. Then, something is done to the world i.e. take action to move oneself or manipulate someone or something. Finally, the checking is required if the goal was made. This led to formulation of Stages of Execution and Evaluation.[1]: 46 Execution formally means to perform or do something. Norman explains that a person sitting on an armchair while reading a book at dusk, might need more light when it becomes dimmer and dimmer. To do that, he needs to switch on the button of a lamp i.e. get more light (the goal). To do this, one must need to specify on how to move one's body, how to stretch to reach the light switch and how to extend one's finger to push the button. The goal has to be translated into an intention, which in turn has to be made into an action sequence.
Thus, formulation of stages of execution:
Evaluation formally means to examine and calculate. Norman explains that after turning on the light, we evaluate if it is actually turned on. A careful judgement is then passed on how the light has affected our world i.e. the room in which the person is sitting on the armchair while reading a book.
The formulation of the stages of evaluation can be described as:
Seven Stages of ActionSeven Stages of Action constitute four stages of execution, three stages of evaluation and our goals. 1. Forming the target. 2. Forming the intention 3. Specifying an action 4. Executing the action 5. Perceiving the state of the world 6. Interpreting the state of the world 7. Evaluating the outcome [1] The difference between the intentions and the allowable actions is the Gulf of execution.[2]
The Gulf of EvaluationThe Gulf of evaluation reflects the amount of effort that the person must exert to interpret the physical state of the system and to determine how well the expectations and intentions have been met.[3]
The seven-stage structure is referenced as design aid to act as a basic checklist for designers' [4] questions to ensure that the Gulfs of Execution and Evaluation are bridged.[1]: 52–53 The Seven Stages of relationship can be broken down into 4 main principles of good design:
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Seven stages of action in human-computer interaction
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