What is Hick's law?

Hick’s law states that the time and effort required to make decision increases as the number of options increases. The decision time increases logarithmically as shown below:

Formula

The mathematical representation of Hick’s law is as follows:

RT = a + b log2 (n) where RT = reaction time (n) = no. of stimuli a & b = constants

When is Hick’s law used?

Hick’s law is used when response time is important in decision-making. It is used to avoid overloading the users with excessive choices and provide relevant options only. However, Hick’s law should not be used when complex decision-making and extensive research are required.

Use of Hick’s law in product design

1. Checkout interface of a website: The checkout interface can be divided into smaller steps, e.g., one step that shows the users their final shopping cart, the next one asking the user to input delivery and contact information followed by the interface that calculates total charges along with shipping charges and shows the total amount to users before asking them to place the order.
2. Microwave: Too many options on a microwave will confuse the user. On the other hand, fewer options will make the user experience easy for the user. The same principles apply to TV remotes and other such appliances.

How to find out the impact of Hick’s law on design

1. Time spent on website: If too little time is spent on the website, that means the user left without exploring or registering. Too much time spent on the website shows that the user perhaps got confused because of the information overload and could not do anything or got distracted from the goal.

2. No. of page views: Too few page views reflect that the navigation might be too complicated for the user to understand. The landing page of a website should be crafted carefully, keeping information overload to a minimum and presenting only the relevant information.

Hick’s law has the following giveaways:

1. Minimize options when response time is critical.
2. Break down complex tasks into smaller steps to reduce the cognitive load on the user.
3. Do not overwhelm the user by highlighting too many options.
4. Categorize the interface to allow the user to go from higher hierarchy to lower, i.e., from broader categories to more specific ones.

Hick’s law is used along with other design principles and other types of product design.