Several studies on time preference have found time inconsistency in both gain and loss preferences. However, the relationship between the two within the same person remains unclear; that is, does an individual who demonstrates time inconsistency for gain outcomes do so for losses as well? This paper reports on individuals’ time inconsistency for gains and losses in a laboratory setting. To obtain a precise comparison of individuals’ time inconsistency for gains and losses, we used Rohde’s “DI -index” :1700–1716, 2018) and (...) measured the level of time inconsistency, rather than merely identifying whether TI was present. This index represents how strongly a person exhibits present bias, and easily extends to the comparison between gain and loss preferences within the same person. Further, it allows the experiment to test for so-called future bias, which has been a focus area in recent time inconsistency literature. It is elicited through a non-parametric method, which avoids any specification errors in the analysis. Our findings are as follows: first, we found future bias in preferences for not only gains but also losses, and we confirmed that this tendency is consistent with previous findings on preferences for gains. Second, a positive correlation between time inconsistency for gains and losses was found at the individual level. Indeed, we could not find a significant difference between the two in most cases. (shrink)

Summary Although the Copernican hypothesis is popularized in Japan by Shiba Kōkan's books published between 1793 and 1805, the whole of the conceptions of the Occidental astronomy remains unknown at that time to most of the Japanese. Through the publication of Ensei kanshō zusetsu in 1823, Yoshio Nankō does achieve posthumously the project designed two years earlier by his young disciple, Kusano Yōjun, to spread this knowledge widely among the society. The book is a great and unprecedented success. Well (...) known nowadays for its appendix (Chidō wakumon) and the influence that its content, while claiming the mobility of the Earth, did exert on the propagation of the heliocentrism in Japan until the very end of the Edo period, the book also provides as we think an unexpected and completely new platform for classical science, being the emissary of certain concepts invented by Shizuki Tadao from his relentless studies of Newtonian mechanics. Once we briefly recount Yoshio's career and discuss the sources and the morphology of his work, we give some arguments towards it. (shrink)