This study investigates the announcement effects of the Bank of Japan’s (BOJ) ETF purchase program on equity prices, focusing on the policy change made on March 19, 2021 when the BOJ announced that it would no longer purchase Nikkei225-tracking and JPX400-tracking ETFs but would purchase more TOPIX-tracking ETFs. A regression of intraday stock returns revealed that the announcement of a future decrease (increase) in the amount of BOJ purchases has the instantaneous effect of decreasing (increasing) stock prices.

Interval games are an extension of cooperative coalitional games, in which players are assumed to face payoff uncertainty. Characteristic functions thus assign a closed interval, instead of a real number. In this paper, we first examine the notion of solution mapping, a solution concept applied to interval games, by comparing it with the existing solution concept called the interval solution concept. Then, we define a Shapley mapping as a specific form of the solution mapping. Finally, it is shown that the Shapley mapping can be characterized by two different axiomatizations, both of which employ interval game versions of standard axioms used in the traditional cooperative game analysis such as efficiency, symmetry, null player property, additivity and separability.

This study investigates the impact of the Bank of Japan’s (BOJ) exchange traded fund (ETF) purchasing program on the stock lending market. In particular, we focus on the fact that stocks held by ETF managers for the BOJ are lendable to other investors in order for them to make a short position in stock market. Using individual stock level data, we show that expansions of the ETF purchase program have substantially increased the supply of stocks in the lending market by changing the behavior of stock holders as the BOJ is expected to be a “buy-and-hold” type of investor. This result implies that such an active stock lending market would help to reduce the side-effects of the ETF program whereas the squeezing effect of the program on supply–demand balance in spot stock markets is mitigated.

In this paper, we investigate the effects of the Bank of Japan's (BOJ) exchange-traded fund (ETF) purchase program on equity risk premia. We first construct a unique panel dataset for the amount of individual stock that the BOJ has indirectly purchased in the program. Then, utilizing the cross-sectional and time-series variations in purchases associated with the BOJ's policy changes, the empirical analysis reveals that: (i) the BOJ's ETF purchases instantaneously support stock prices on the days of purchases, and (ii) the instantaneous positive effects on stock prices, combined with the countercyclical nature of the BOJ's purchases, have decreased the market beta and coskewness of Japanese stocks, thus leading to an economically significant decline in risk premia.

An interval game is an extension of characteristic function form games in which players are assumed to face payoff uncertainty. The characteristic function thus assigns a closed interval, instead of a real number. In this paper, we propose a new solution mapping of two-person interval games and three different axiomatizations of the solution mapping are provided.

While the European Central Bank experienced severe overbidding in the conduct of its fixed-rate operations, the Bank of Japan has not. Theoretical analyses argue that the reason is that the currently accommodative financial environment in Japan has made bidders' objective functions locally satiated. We conduct an experiment with fixed-rate operations and find that, even as participants' initial demands are large, an explosion of bids does not arise if the objective functions are sufficiently satiated. We also estimate the bid functions from the experimental data and a simple calibration based on the functions indicates that fixed-rate operations are vulnerable to overbidding even when some degree of satiation is preserved.

This paper studies bidding behaviors in fixed-rate funds-supplying auctions using a simple game-theoretic model. While the existing literature argues that such auction schemes are vulnerable to the overbidding problem, the bid-to-cover ratio for the Bank of Japan's current fixed-rate operations has remained stable. After reviewing the stylized repo game and the mechanism of overbidding under the fixed-rate operations, we argue that the current framework of fixed-rate funds-supplying auctions operated by the Bank of Japan and the recent accommodative financial environment make bidders' loss functions locally satiated. Given this argument, it is shown that any stable bid-to-cover ratios other than either undersubscription or overbidding can be supported by an equilibrium. Finally, we empirically find that the ratio under the Bank of Japan operations has been influenced by such financial conditions proxied by market interest rates and term spreads. (C) 2012 Elsevier Ltd. All rights reserved.

We apply the farsighted stable set to two versions of Hotelling's location games: one with a linear market and another with a circular market. It is shown that there always exists a farsighted stable set in both games, which consists of location profiles that yield equal payoff to all players. This stable set contains location profiles that reflect minimum differentiation as well as those profiles that reflect local monopoly. These results are in contrast to those obtained in the literature that use some variant of Nash equilibrium. While this stable set is unique when the number of players is two, uniqueness no longer holds for both models when the number of players is at least three. (C) 2011 Elsevier B.V. All rights reserved.