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What is the definition of Friedman test? 

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The Friedman test is a nonparametric method used to analyze data from a randomized complete block design. It is a robust alternative to parametric methods and is widely applied in various fields such as agriculture, biology, business, education, and medicine. The test is used to determine if there are treatment effects present in the data. After rejecting the null hypothesis of no treatment effects, post-hoc pairwise comparisons are conducted to identify where the differences occur. As the number of groups increases, the number of required comparisons also increases, which can lead to an increased type I error. Several studies propose methods to address this issue, including suggesting expressions that facilitate the plotting of the Friedman test and deriving the sampling distribution of the suggested expression. These methods aim to reduce the number of required tests, maintain the type I error close to the nominal value, and provide a better understanding of where the treatment effects occur .

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The paper provides the definition of the Friedman test as a statistical test used to assess the independence of repeated experiments resulting in ranks.
The paper provides a definition of the Friedman Test as a statistical test used to analyze tables of ranks, such as those from a wine contest.
The definition of the Friedman test is not explicitly mentioned in the provided paper.
The paper provides a definition of the Friedman test as a nonparametric method used to analyze data from a randomized complete block design.

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Does Monetary Policy Matter? A New Test in the Spirit of Friedman and Schwartz?3 answersMonetary policy does matter, and its effects can be tested using a narrative approach similar to the one used by Friedman and Schwartz. Romer and Romerused a narrative approach based on Federal Reserve documents to create a dummy variable representing periods when the Federal Reserve contracted in response to inflationary pressures. However, Leeperargues that this dummy variable is predictable from past macroeconomic variables, indicating an endogenous response of policy to the economy. Furthermore, unpredictable changes in the dummy variable do not generate dynamic responses that resemble the effects of monetary policy. On the other hand, Romer and Romerfind that shifts to anti-inflationary policy led to a significant rise in the unemployment rate, suggesting that monetary disturbances have real effects. They also find that these effects are persistent and account for a considerable fraction of postwar economic fluctuations. Evidence from the interwar era also supports the idea that monetary disturbances have large real effects.
What is Mann-Kendell test?4 answersThe Mann-Kendall test is not mentioned in any of the provided abstracts.

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