Two modes of thinking for developing social theories have been identified. One is downstream thinking, and the other is upstream thinking. This paper tries to argue that the latter mode of upstream thinking is pertinent for clarifying the change generation process in socio-economic systems. This paper also asserts that two types of change generation logics for socio-economic systems have been identified based on this up-stream mode of thinking. The first one is micro-macro-link-based approach that attempts to elucidate the change generation in socio-economic systems from the viewpoint that there are hierarchically divided entities in society such as macro and micro, structure and agency. In the case of Imada’s Self Organizing Paradigm, it tries to elucidate the changes in society, starting from the actor’s reflection upon the macro situations. In the case of Archer’s Morphogenetic approach, it tries to elucidate the changes in society by examining the sequential steps consisting of structural conditioning, social interactions, and structural elaboration. The second one is new combinations of heterogeneous-elements-based approach that attempts to elucidate the change generation in society from the viewpoint that heterogeneous elements including non-humans are combined together to produce new configurations of socio-economic system. The change generation logic based on the new combination of such heterogeneous elements emphasizes that new configurations of socio-economic systems are created by connecting various actors （including non-humans and bodies） one after another over time and space. Theories that try to incorporate this change generation logic include TEN（Techno-Economic Network）, ANT（Actor-network Theory） and practice theory. The characteristics of these theories are examined and compared with each other in this paper.

 In this study, I analyzed the impact of the worldwide spread of a new coronavirus （COVID-19） on KAKEN international collaborative research activities since December 2019, based on interim reports （KAKEN database） of 322 participating researchers. A statistically significant relationship was found between the level of research achievement and the perceived impact of COVID-19. In contrast, there were no significant differences between research achievement and gender, position, or field of study; there was a significant increase in the number of researchers who expected greater COVID-19 impact in studies after April 2020. The decision tree analysis with research achievement or COVID-19 impact perception as the objective variable suggested the impact of the year of research implementation and total research funding. Since the risk of research stagnation due to pandemics, etc. is expected to continue in the future, I discussed risk management for the continuation and development of international collaborative research.

 In statistical practice, the tabulation of data is the final step toward publication. Guidelines for the selection of tabulation are not necessarily well developed.

 “Median” is selected as the third tabulation item after “mean” and “standard deviation” in the tabulation of food intake in the National Health and Nutrition Examination Survey. Since there are more cases where the tabulation of “median” is zero as we move closer to the detailed classification, it is suggested that “zero data ratio” should be tabulated instead of “median”. In this paper, I explain the characteristics of this data measurement method and distribution.

 Next, the “hurdle model” by Cragg （1971） is proposed to be a statistical model for processing data with these characteristics. As the first conclusion of this paper, the discriminant criterion is proposed, that the data is appropriate for the application of the “hurdle model” as a guideline for tabulating the zero data ratio and non-zero data distribution.

 Finally, the distribution of the micro data generated from the National Survey of Family Income and Expenditure is shown to be completely different from that of the original data because the “hurdle model” has not been considered in the generation of the micro data for general use. The improvements using the “hurdle model” are proposed.

 In 2020, the spread of COVID-19 largely changed people's daily lives. People were asked to refrain from moving across prefectural borders and to avoid the Three Cs. This had a great impact on the job-hunting activities of university students. Job hunting for university students commences March 1st every year. During this period, large-scale joint company information sessions are held in various locations, however most of these were canceled in 2020.

 What kind of influence did COVID-19 have on the students who needed decide their future career and where to work in such a world? In particular, how did the restricted movement and diminished relationships with people affect students' employment consciousness? In this study, we clarify through surveys how students belonging to local universities were affected by COVID-19 during the important process of early stages of job hunting, and how their employment consciousness was affected. As a result, an increased emphasis on company size and human relations was confirmed.

 It has been pointed out that elderly people have problems with decreased physical activity and social isolation due to the influence of Covid-19. The purpose of this study was to understand the actual condition of Covid-19 anxiety in the elderly living in the mountainous areas of Japan. For the analysis, we used the data of the CoHRE study conducted by Shimane University. Our findings suggest that older adults who have a friend and being a patient with lifestyle-related diseases are more likely to feel anxiety for Covid-19.