فاطمه ندافی

Many researchers have attempted to explain the phenomenon of medium-term return continuation using modern financial theories. The excess return gained in the momentum investment strategy, in fact, compensates for unknown risks that current theories are unable to explain. Research indicates that various strategies can be beneficial at different maintenance periods. Various strategies generally involve a simple method in which they are formed based on the criterion of return over a certain period in the past and are maintained for a corresponding period in the future. Each investment strategy tends to generate excess returns based on the predictability of short-term price movements, as indicated by past performance. The purpose of this study is primarily to investigate the usefulness of residual momentum and conventional momentum strategies in the short-term and long-term. The time period of this study is from 2009 to 2018, and the general approach for calculations is based on the method described by Jegadeesh and Titman (1993), Blitz et al. (2011), and Blitz et al. (2020). The results of this study show no significant difference between residual and conventional momentum strategies in both short-term and long-term periods, indicating that both approaches exhibit similar risk-adjusted performance and forecasting capabilities.

The nature of heterogeneity issues within the context of Iranian, English language learning contexts in high schools is one of the under-researched lines of inquiry. For this aim, a researcher-made, Likert-type questionnaire whose items were initially validated through a multi-stage, exploratory research design among 30 teachers was distributed among some 67, Iranian EFL teachers with different degrees of experience (less vs. more) to find the teachers’ concerns/challenges and their strategies to tackle them. The findings suggested that the concerns behind heterogeneous classes were not consistent regrading weak and strong students. In the second place, it became evident that the order of tendency towards adopting the four enunciated strategies was not the same in the two less and more experienced teachers. Possible interpretations regarding teacher outlook as mapped on ‘teacher experience’ to target heterogeneity issues were presented in the end.