ãðèªã¿åããŸããðããJapanese Foreign Exchange Interventions, 1971-2018:Estimating a Reaction Function Using the Best ProxyãïŒå è¡ç 究解説 No.16ð2023/11/05
IntroductionïŒåæ¥è«æã¯æ©ãã«ä»äžãããð
ç§ãããããåæ¥è«æã®å·çã«
åããããææããã£ãŠåããŸããð
äœäºãã¢ãŠããããåæã®ã€ã³ãããã
倧äºã§ãããšãnoteã§æ¯æ¥çºä¿¡ããŠããŸãã
ããã¯ãã©ã®ãããªå
容ã§
ãã£ãŠãåœãŠã¯ãŸããŸãð
è«æãäžæŠã«èªãã§ã
èšæ¶ã«æ®ã£ãŠããªãã£ãã
倧åãªèгç¹ãå¿ããŠããŸã£ãŠãããããã
åæ¥è«æã®é²æã¯æ»ã£ãŠããŸããšæããŸã
ã ããããããã®ãnoteãããã«æŽ»çšããŠ
åæ¥è«æã1ïŒ
ã§ã
宿ã«åããŠé²ããŠãããããšæããŸã
ç§ã®åè«å·çãžã®è»è·¡ã
ã©ãããæèªãã ããð
ä»åã®åèæç®ð¥
ä»åãèªã¿é²ããŠããè«æã¯
ãã¡ãã®URLã«ãªããŸãð
ãJapanese Foreign Exchange Interventions, 1971-2018: Estimating a Reaction Function Using the Best Proxyã
Takatoshi Ito(a), Tomoyoshi Yabu(b)
(a) School of International and Public Affairs, Columbia University, and GRIPS, Tokyo
(b) Department of Business and Commerce, Keio University
Japanese Foreign Exchange Interventions, 1971-2018: Estimating a Reaction Function Using the Best Proxy
December 12, 2019
Takatoshi Ito(a), Tomoyoshi Yabu(b)
(a) School of International and Public Affairs, Columbia University, and GRIPS, Tokyo
(b) Department of Business and Commerce, Keio University
ååã®ã埩ç¿ãð
7. Concluding Remarks
This paper confirms that âAdjusted MOF FEEFâ is the best proxy for settlement-based interventions.
In fact, the proxy explains 99.8% of the movements of settlement-based interventions.
The monthly intervention data are presented in the data appendix and are also available on the authorsâ websites.
At least in the monthly frequency, it has become possible to research topics related to Japanese interventions from August 1971 to the present day.
One caution: most researchers are interested in transaction-based interventions when analyzing the effectiveness of interventions or in the reaction function of the monetary authorities since the exchange rate reacts to the buy and sell in the market transactions.
The difference is the last two business days of the month. Therefore, when we use settlement-based interventions as transaction-based interventions, we must consider the exchange rate on the third-to-last business day as representative of the monthly exchange rate when analyzing exchange rate returns.
ãã®å
è¡ç ç©¶ã¯ã調æŽããã MOF FEEFããååŒæ±ºæžããŒã¹ã®ä»å
¥(settlement-based interventions)ã®æè¯ã®ä»£ç倿°(Proxy)ã§ããããšã確èªããŠããŸã
å®éã代ç倿°ã¯æ±ºæžããŒã¹ã®ä»å
¥ã®åãã®99.8%ã説æããŠããããšãååž°åŒã®æšèšããããããŸãã
æ¯æã®ä»å
¥ããŒã¿ã¯ããŒã¿ä»é²ã«ç€ºãããŠãããèè
ã®ãŠã§ããµã€ããããå
¥æã§ããŸãð
å°ãªããšãæ¯æã®é »åºŠã§ã1971幎8æããçŸåšãŸã§ã®æ¥æ¬ã®ä»å
¥ã«é¢é£ãããããã¯ã調æ»ããããšãå¯èœã«ãªããŸãã
This paper has analyzed the reaction function of the Japanese monetary authorities.
The following points stand out.
First, the reaction functions were not stable over time. In fact, we observed four break dates and thus five regimes: August 1971 to November 1981, December 1981 to May 1995, June 1995 to December 2002, January 2003 to July 2004, and August 2004 to March 2018.
These policy shifts might be associated with changes in the impact of interventions on the yen/ dollar rate.
Therefore, we need to exercise caution when analyzing the effectiveness of interventions.
Second, the neutral band of the reaction function widened over time, apart from during the period in which it did not exist, between January 2003 to July 2004.
This implies that the Japanese monetary authorities have experienced increased political pressure from other countries over time concerning their intervention or proposed intervention in the foreign exchange market.
Third, the cost of selling-dollar interventions was higher than the cost of buying-dollar interventions.
This implies that the monetary authorities were more inclined to resist yen appreciation.
ãŸããã®å
è¡ç ç©¶ã§ã¯ãæ¥æ¬ã®éèåœå±ã®åå¿é¢æ°ãåæããŠããŸã
ãããŠã以äžã®äºé
ãéç«ã£ãŠãããã€ã³ãã§ãããšèšããŸã
ãŸããåå¿é¢æ°ã¯æéã®çµéãšãšãã«å®å®ããŸããã§ãã
å®éã1971幎8æãã1981幎11æãŸã§ã1981幎12æãã1995幎5æãŸã§ã1995幎6æãã2002幎12æãŸã§ã2003幎1æãã2004幎7 æãŸã§ãããã³2004幎8æãã2018幎3æãŸã§ã4 ã€ã®æ§é å€å(four break dates)ãããããããã£ãŠã5ã€ã®æ§é (regimes)ã芳å¯ãããŸãã
$$
\\Ordered Probit Model \\ \\IInt_t = \begin{cases}
+1 &\text{if } \mu_2 < y_t^* \\
0 &\text{if } \mu_1 < y_t^* < \mu_2 \\ -1&\text{if } y_t^* < \mu_1 \cdots(2)
\end{cases} \\ \\ \\where y_t^*=X_t\beta +\epsilon_t \\with \epsilon_t \backsim i.i.d N(0,\sigma^2) and\\ \\X_t\beta=\beta_1(s_{t-1}-s_{t-2})+\beta_2(s_{t-1}-s_{t-1}^{MA})+\beta_3 IInt_{t-1}
$$

ãããã®æ¿ç倿Žã¯ãå/ãã«ã¬ãŒãã«å¯Ÿããä»å
¥ã®åœ±é¿ã®å€åã«é¢é£ããŠããå¯èœæ§ããããŸã
ãããã£ãŠãä»å
¥ã®æå¹æ§(analyzing the effectiveness of interventions)ãåæããéã«ã¯æ³šæãå¿
èŠã§ããããšãããããŸãð
第äºã«ãä»å
¥ã宿œãããããšã®ãªãåå¿é¢æ°ã®äžç«åž¯(the neutral band of the reaction function)ã¯ãããïŒäžç«åž¯ïŒãååšããªãã£ã2003幎1æãã 2004幎7æãŸã§ã®æéãé€ããæéã®çµéãšãšãã«æ¡å€§ããŸããð
ããã¯ãæ¥æ¬ã®é貚åœå±ããå€åœçºæ¿åžå Žãžã®ä»å
¥ãŸãã¯ä»å
¥ã®ææ¡ã«é¢ããä»åœããã®æ¿æ²»çå§åã®å¢å€§ãæéã®çµéãšãšãã«çµéšããããšãæå³ããŸã
第äžã«ãåè²·ããã«å£²ãä»å
¥ã®ã³ã¹ã(the cost of selling-dollar interventions)ã¯ãå売ããã«è²·ãä»å
¥ã®ã³ã¹ã(the cost of buying-dollar interventions)ãããé«ãã£ããšããããšã§ãðŽ
ããã¯ãéèåœå±ã"åé«ã«æµæããåŸåã匷ãã£ãããš"ãæå³ããŠãããšèšããŸããð
æ¬æ¥ã®è§£èª¬ã¯ããããŸã§ãšããŸã
ãã®ãããªæŽå²ãå
è¡ç ç©¶ããã£ããçè§£ããäžã§ãåæ¥è«æå·çã«åãçµãã§ããããã§ã
èªã¿çµããå è¡ç ç©¶ð
ãæ¥æ¬ã®çºæ¿ä»å
¥ã®åæããäŒè€éæã»è
çµæžç ç©¶ãVol.54 No.2 Apr. 2003
ãEffects of the Bank of Japanâs intervention on yen/dollar exchange rate volatilityã21 November 2004
Toshiaki Watanabe (a), Kimie Harada(b)
ãThe Effects of Japanese Foreign Exchange Intervention: GARCH Estimation and Change Point Detectionã
Eric Hillebrand Gunther Schnabl Discussion
Paper No.6 October 2003
ç§ã®ç ç©¶ããŒãã«ã€ããŠð
ç§ã¯ãçºæ¿ä»å
¥ã®å®èšŒåæããããŒãã«
åæ¥è«æãå·çããããšèããŠããŸãð
æ¥æ¬çµæžãèãããšãã«ãçºæ¿ã¬ãŒãã«ãã£ãŠ
貿æååŒãçµåžžåæ¯ãå€åããã
æ ªã蚌åžã嵿š©ãšãã£ãéèè³ç£ã®åççã
å€åããããšæ¥æ¬çµæžãšçºæ¿ã¬ãŒããšã¯
åã£ãŠãåããªãçžãããã®ã§ãð
ïŒåðŽã ãã«ïœ¥ïœ¥ïœ¥ïŒ
çµæžã·ã§ãã¯ã«ãã£ãŠ
çºæ¿ã¬ãŒããå€åãããš
ãã®åœ±é¿ã¯ç§ãã¡ã®ç掻ã«å€§ãã圱é¿ããŸã
ã ãããããçºæ¿ã¬ãŒãã®å®å®æ§ã
æ
ä¿ãããããªçºæ¿ä»å
¥ã¯ãã¯ãçµæžæ¿çã«
ãããŠãéåžžã«éèŠãªæçŸ©ãæã£ãŠãããš
æšæž¬ããŠããŸã
決ããŠåŠéšçãæ¥œããŠå·çã§ãã
ç°¡åãªããŒããéžæããŠããããã§ã¯ç¡ããšä¿¡ããŠããŸã
ãã ããã®åæ¥è«æãããåãããšã
ç§ã®åŠççæŽ»ã®é倧æãšãªãããšã¯äºå®ãªã®ã§
æåŸãŸã§ã³ãã³ããšåãçµãã§åããŸãð¥
æ¬æ¥ã®è§£èª¬ã¯ã以äžãšããŸãð
ä»åŸãçµæžåŠçè«éãªãã³ã«
瀟äŒèª²é¡ã«å¯ŸããçµæžåŠçèŠç¹ã«ãã説æãªã©
ææçŸ©ãªå
容ãçºä¿¡ã§ããããã«
åªããŠãŸãããŸãã®ã§
ä»åŸãšãå®ãããé¡ãããŸãð¥º
ãã¬ãžã³ã®ã玹ä»ð
ãã¡ãã®ãã¬ãžã³ã«ãŠ
åæ¥è«æå·çãžã®è»è·¡
ãšãã»ã³ã·ã£ã«çµæžåŠçè«éããªãã³ã«
ãåœéçµæžåŠðãã®åºç€çè«ããŸãšããŠããŸã
ä»åŸãããã«ã³ã³ãã³ããæ¡å
ã§ããããã«åªããŠåããŸãã®ã§äœåãããããé¡ãç³ãäžããŸãð
æåŸãŸã§ãæèªããã ãèª ã«æé£ãããããŸããïŒ
ãããŸã§ãç§ã®èŠè§£ãæã£ãããšã
ãŸãšããããŠããã ããŠãŸãã
ãã®ç¹ã«é¢ããŸããŠããäºæ¿ãã ããð
ãã®æçš¿ãã¿ãŠãã ãã£ãæ¹ã
ã»ãã®å°ããªäºã§ãåŠã³ããã£ãïŒ
èãæ¹ã®åŒãåºããå¢ããïŒ
èªæžããåŠã¹ãããšãå€ãïŒ
ãªã©ãªã©ããã©ã¹ã®åç©«ããã£ãã®ã§ããã°
倧å€å¬ããæããŸãããæçš¿äœæã®å¥å©ã«å°œããŸãïŒïŒ
ãæ°è»œã«ã³ã¡ã³ããããããã¹ããð
ãããŠããå·®ãæ¯ããªããã°
ãã©ããŒïŒã·ã§ã¢ããé¡ããããã§ãð
ä»åŸãšãäœåãããããé¡ãããããŸãïŒ
ãããªãšæã£ããå¿æŽãããïŒ
ãããããã°ãå¿æŽãé¡ãããŸãïŒ
ããã ãããããã¯ã¯ãªãšã€ã¿ãŒãšããŠã®æŽ»åè²»ã«äœ¿ãããŠããã ããŸãïŒ
åŒãç¶ãäœåãããããé¡ãããããŸãð