the true mapping from precedents in architectural ideation

architecture precedents are important sources to educate architecture students. inappropriate use of precedents may lead to design fixation. the use of precedents is common in architectural design and there is no clear difference between copy and inspiration. therefore it is important to know what the true mapping is and how we can evaluate the relation between precedent and design outcome. in this paper with the aim to recognize the true mapping, we describe the different mapping models and analyze those based on bloom taxonomy from remember layer to understand, apply, analyze and create layers. based on this model 20 steps must be done: recognizing, recalling, remember, interpreting, exemplifying, classifying, summarizing, inferring, comparing, explaining, executing, implanting, differentiating, organizing, attributing, checking, critiquing , generating, planning and producing. the eilouti model is more comprehensive than others and comprise all layers, but it is a complicated model and difficult to reuse by educators. the models compared based on new findings of design theories. six models are categorized in normative models and one is categorized empirical. therefore there is no mapping model based on studding the design behavior of expert designers, observing designers during design process and interacting between designer and design idea presentation. thus none of these models didn’t use by other researchers or in architecture education. but visual analogy model became an educational method because of its empirical merit. we investigated all different methods that evaluate relation between precedent and design idea. there are two approaches, first approach evaluate idea without considering precedent. in this approach good idea is creative ones and four creativity parameters, novelty, quality, quantity and diversity, are evaluated in qualitative, quantitative, or synthesis methods. second approach evaluates design idea in comparison with precedent based on originality, design fixation and similarity type definitions. some evaluation methods such as quantity, diversity or repeated ideas are used in conditions that designers produced all possible ideas and are not usable in normal conditions. some methods need to predict all possible solutions by researcher and count all precedent features that almost impossible in architectural design. therefore most of the quantitative methods are not usable in architectural education and qualitative methods based on expert judges are preferred. we presented four mapping definitions based on four different approaches, mapping process, creative idea, design fixation, and structural mapping. for every definition there is an evaluation method. the comprehensive definition is offered that true mapping is going beyond levels of thinking and achieve creation level that leads to structural similarity and enhances novelty and quality of design idea. the similarity between source and idea and novelty and quality of idea must be evaluated based on this definition. knowing the true definition and having a mapping process model cannot guarantee the design results. students copy the source examples because lack of design ability, idea presentation skills or ideation ability. thus there is need to purposeful and designed practices to help students. finding educational ways to enhance students’ ability in true mapping are recommended for future studies.