Many companies have been working on reducing energy consumption these days. However, it could also reduce efficiency of office work because of worsening the office environment by energy saving, for example, turning air-conditioning down could make the indoor air environment of office workplace worse and uncomfortable, and it may reduce their work motivation and then also reduce work efficiency, what is called “intellectual productivity”. It is therefore necessary to analyze not only the direct relationship between change of workplace environment and intellectual productivity but also its varying mechanisms in order to achieve energy saving and higher intellectual productivity at the same time. Quantitative analyses about certain effects of workplace environment to office productivity have been already done in conventional studies. Although the degree of each environmental effect can be compared from the studies, it is necessary to measure the varied factors and their varying process leading to productivity change in order to know the essential relationship between the environmental factors and the productivity changes.
The purpose of this study is to propose a systematic method consisting of various statistical processes as a framework of mechanism analysis of productivity changes. The framework was verified by case studies of some different varied environmental factors. In the framework, a subject experiment is conducted under varying workplace environment and (1) change of environment, (2) intellectual productivity, (3) individual trait of the subject and (4) psychological change are measured. And then the relationships between them are analyzed. Concretely, a general mechanism model including every factor causing productivity changes and a procedure to quantify the changing mechanisms were proposed as the analysis framework. The quantification procedure consists of measuring the factors of general mechanism model and statistical process of measured data. Some serviceable approaches were also proposed in each process.
The effectiveness of the framework was verified by the case studies of three different environmental factors which are (1) illumination, (2) airflow and (3) multiple environmental factors. As one of the results of their analyses, for example, it was found that there were two mechanisms which affect intellectual productivity from airflow environment. One reduces feeding of fatigue by airflow comfort and improves productivity, while the other directly improves productivity by airflow perception. In this way, it was confirmed that the framework could show the mechanism to interpret productivity changes by the change of workplace environment without contradiction. In addition, some improvement plans of workplace environment to improve productivity could be proposed by using the results of the analyses.
In further study, it is required to measure both the productivity changes and the overall factors of general mechanism model and to analyze them with the proposed method as a case study in order to improve the proposed analysis method.