Editing Tobin tax (section)

=====Empirical studies=====
{{See also|#Tobin tax proponents response to empirical evidence on volatility}}

In most of the available ''empirical'' studies however, no statistically significant causal link has been found between an increase in [[transaction cost]]s (transaction taxes or government-controlled minimum brokerage commissions) and a reduction in volatility—in fact a frequent unintended consequence observed by 'early adopters' after the imposition of a financial transactions tax (see Werner, 2003)<ref>{{Cite journal|last=Werner|first=Ingrid M.|year=2003|title=Comment on 'Some Evidence that a Tobin Tax on Foreign Exchange Transactions may Increase Volatility'|journal=European Finance Review|volume=7|issue=3|pages=511–514|citeseerx=10.1.1.459.5056|doi=10.1023/B:EUFI.0000022151.50261.40}}</ref> has been an ''increase in the volatility'' of stock market returns, usually coinciding with significant declines in liquidity (market volume) and thus in taxable revenue (Umlauf, 1993).<ref name="Umlauf, Steven R. 1993">{{Cite journal|last=Umlauf|first=Steven R.|year=1993|title=Transaction taxes and the behavior or the Swedish stock market|journal=Journal of Financial Economics|volume=33|issue=2|pages=227–240|doi=10.1016/0304-405X(93)90005-V}}</ref>

For a recent evidence to the contrary, see, e.g., Liu and Zhu (2009),<ref name="Liu 2009">{{Cite journal|last1=Liu|first1=Shinhua|last2=Zhu|first2=Zhen|name-list-style=amp|year=2009|title=Transaction Costs and Price Volatility: New Evidence from the Tokyo Stock Exchange|journal=Journal of Financial Services Research|volume=36|issue=1|pages=65–83|doi=10.1007/s10693-009-0063-x|s2cid=154120891}}</ref> which may be affected by [[selection bias]] given that their Japanese sample is subsumed by a research conducted in 14 Asian countries by Hu (1998),<ref>{{Cite journal|last=Hu|first=Shing-yang|year=1998|title=The effects of the stock transaction tax on the stock market: Experiences from Asian markets|journal=Pacific-Basin Finance Journal|volume=6|issue=3–4|pages=347–364|doi=10.1016/S0927-538X(98)00017-1}}</ref> showing that "an increase in tax rate reduces the stock price but has no significant effect on market volatility". As Liu and Zhu (2009) point out, [...] the different experience in Japan highlights the comment made by Umlauf (1993) that it is hazardous to generalize limited evidence when debating important policy issues such as the STT [securities transaction tax] and brokerage commissions."