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Version: 0.1 
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Changes: First version. IKbandwidth, DCdensity and RDestimate created and working. 
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Version: 0.2 
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Changes: Added separate function for kernel weights, S3 methods for plotting and summarizing RD objects. 
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Version: 0.21 
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Changes: Fixed bug in RDestimate when frame=TRUE and no covariates. 
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Version: 0.22 
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Changes: Fixed handling of missing values. 
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Version: 0.3 
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Changes: Improved plot method, fixed some various bugs.
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Version: 0.31 
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Changes: Added plot.RD documentation. 
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Version: 0.4 
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Changes: Made compatible with CRAN. 
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Version: 0.41 
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Changes: Fixed submission issue. 
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Version: 0.42 
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Changes: Submission issue. 
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