The suggested threshold to reduce data noise for a factorial experiment

Document Type : Research Paper


1 Department of Statistics and Informatics, Mosul University, Iraq

2 Department of Statistics, Baghdad University, Iraq


In this research, a factorial experiment (4*4) was studied, applied in a completely random block design, with a size of $2^5$ observations, where the design of experiments is used to study the effect of transactions on experimental units and thus obtain data representing experiment observations that  The difference in the application of these transactions under different environmental and experimental conditions It causes noise that affects the observation value and thus an increase in the mean square error of the experiment, and to reduce this noise, multiple wavelet reduction was used as a filter for the observations by suggesting an improved threshold that takes into account the different transformation levels based on the logarithm of the base $J$  and obtaining several values for the suggested threshold and applying then Haar wavelet function With the cut-off hard and mid threshold and Comparing the results according to several criteria.


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Volume 13, Issue 1
March 2022
Pages 3861-3872
  • Receive Date: 06 November 2021
  • Revise Date: 22 December 2021
  • Accept Date: 01 February 2022