The Miller’s Law Applied To User Experience

UX Design | 06th November 2017

The relationship between Miller’s Law (1956) with the UX of the 20th century

What does Psychology and User Experience have in common? Everything. And that is the reason why we went to Dr. Lídia Oliveira, a Clinical Psychologist, who helped us with this research and several bibliographic references of the scientific information included in this article.

User experience has, as its main cornerstones, several studies of Human-Computer Interaction (HCI) and there are five laws regarded as crucial in order to have a better understanding of the UX world. These are five generic laws which can be applied to the current practice of a proper User Experience Design.

Studies conducted by George Miller indicate that most people solely store 5 to 9 items of information in their short-term memory. This rule can and must be easily applied to presentations, listings and menus.However, as it happens for instance with a clothing e-commerce website, it is not mandatory to only list 5-9 products per page, since our intention is not to make the user memorize things, but to see these products.

First, the information is received in the sensory storage, for a fraction of seconds after the stimulus is gone, then it is moved to the short-term storage, which only retains a certain amount of information for less than 1 minute. After going through the short-term storage, information is forgotten or, if it happens to be processed, by repetition for instance, it can reach the long-term storage, where it can stay indefinitely in that compartment of unlimited  capacity. 

Most people solely store 5 to 9 items of information in their short-term memory

The short-term memory (STM) is a simple registration system for the active items, consisting on their immediate recollection, and it can be analyzed through three different dimensions, with these being the capacity, the length and the codification or processing (Pinto, 1997). The capacity is the amount of information which can be stored, and this is limited in terms of the number of items stored, the length of the items and the availability of mental resources to carry out the STM operations. There are limits in what concerns the amount of information that one can retain in a given moment, and there are also limits in the quickness through which one can use the cognitive functions to process the information received by the system

One of the most used evidences to prove this is the memory range of numbers. The results obtained from it, when applied to young adults with an average education, are around seven digits, plus or minus two, just like Miller (1956) had proposed with his idea that the immediate memory or short-term memory can hold around 7±2 categorized units (Pinto, 2011). The length is the amount of the time during which the information is retained, and this is also limited, ranging from 15 to 30 seconds (Atkinson & Schiffrin, 1971), without requiring a renovation of information through repetition.

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Bibliographic references:

Miller, G. A. (1956). The magic number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63, 81-97.

Atkinson, R. C., & Shiffrin, R. M. (1971). The control of short-term memory. Scientific American, 225, 82-90

Pinto, A. C. (1997). Cognição, aprendizagem e memória. Porto: Ed. do autor.

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