a

b

c

d a Information huntingUsers looking for interaction relevant clues from the product.b Information processing Clues are processed inside of the human brain to help users make their decisions. c Physical interaction Users interact with the product.d Product reactionThe interaction leads to the product reaction.

meta-phase

...usermotivation

productreaction1 2 n

interaction complexity

interaction diffuculty

Mental effort focused interaction modelThe two major causes of mental effort exerted are interaction complexity and interaction diffi-culty. Complexity refers to the number of steps in a process, and difficulty refers to the mental effort exerted in completing a single step in the process.

Characteristics considered in the evaluation model

a

b

c

d

a

b

c

d

Make sure the information is easy for users to find.Information Familarity Information will be more easily get users’ attention if users know what they are looking for to some degree. Information IntensityWhether information is obvious enough for users to find. Information Interference Whether users will be disturbed by some other information, which is quite similar to the information users are looking for.

InformationHunting

PhysicalInteraction

Make sure the user decision is transferred to the product correctly.Interaction RestrictionWhether users are required a lot of concentration in order to deliver their decision correctly.

Characteristics considered in the evaluation model

a

b

c

d

InformationProcessing

Similar information has been encountered by the users before.

Users have no idea how to interact.

nature

second nature

familiar

logical

meaningless

opposite

Users’ innate quality. information will be processed automatically and unconsciously.

Information also will be processed automatically and unconsciously. Comes from frequent, consistent practice.

Users need to apply logical thinking to deduce the decision.

The required interaction conflicts with users’ existing cognition

Characteristics considered in the evaluation model

How many phases are included in the whole process.A lot of mental effort will be saved by reducing unnecessary phases.

informationprocessing

informationtransduction

Nature

Second nature

Familiar

Logical

Meaningless

Opposite

information hunting & physical interaction

motivation reaction1 2 3 ... nFamiliarity

Interference

Intensity

Restriction

interaction evaluation model

width = the negative influence of wrong interaction

The output of certain interaction evaluation.

informationprocessing

informationtransduction

Nature

Second nature

Familiar

Logical

Meaningless

Opposite

information hunting & physical interaction

motivation reaction1 2 3 4

Familiarity

Interference

Intensity

Restriction

The application of interaction model in the actual design process

phase 1 phase 2 phase 3 phase 4evaluation model based user test problem discovery problem evaluation problem solving

user test model