Comparison of the Stock Price Clustering of stocks which are traded in the US and Germany—Is XETRA more efficient than the NYSE?

We analyze intraday trades of German stocks (Daimler Chrysler and SAP) that are traded simultaneously at the German stock market XETRA and the New York Stock Exchange (NYSE). At first glance, the stock price clustering seems to be less pronounced at the NYSE. But after converting Euro-prices into Dollar-prices, we obtain the result that the clustering is stronger at the NYSE indicating that XETRA is more efficient with respect to this measure. This difference in the clustering at the different stock markets should not be observable if the no-arbitrage condition would hold. We also discuss several explanations, like ease of negotiation, convenience and rounding, attraction, odd pricing, and aspiration level for stock price clustering. As a result we see that no model is able to capture all of our empirical observations.