Recently I got the question below which is somewhat related to the subject of this thread.
When adding mutliple zero-rings, it appears there is a limit to how close together they can be added. For example, if I insert a zero-ring at ring number 15, the next "individual" (for lack of a better word) zero-ring only be added at ring 22. In other words, if I try to add a zero-ring at position 18, it is added adjacent to the zero-ring I added at 15. If I add a zero-ring at position 19, same thing - it is not added at position 19, but rather adjacent to ring 15, and so on, until I reach position 22, at which point the zero-ring is inserted at the correct position (here, position 22).
I think there are two reasons for this feature of not being allowed to put single or groups of zero rings too tight together:
1. It is not clear that you know what you are doing when you put them too tight... You might create any pattern you want that way
without seeing the sample... It is questionable if that is good dendrochronology...
2. The normalization methods will not do what you might expect them to do when there are too few actual rings in a sequence:
2A. For e.g. the Baillie/Pilcher method you are working with a "sliding window" of five rings where the normalization value is calculated
for the middle ring of these. (See the Toolbox for normalization to understand the difference between P2Yrs, Ba/Pi, Hollstein.)
When that sliding window is positioned so that there are zero rings within the window, the normalization calculus deteriorate
as the actual rings (for the mean value calculation) within the sliding window are less than five.
The extreme would be a single ring with two zero rings on each side. It is difficult to make a meaningful normalization out of that!
So for the normalization, it is not good to have VERY short sequences with actual tree rings!
2B. Zero rings do not part in the correlation calculus.
To overcome your problem, I think that you have to fake your rings by splitting existing rings.
Like Torbjörn recently pointed out, he had sometimes thought that he knew very well where to put the zero ring, though when consulting
CooRecorder he had found the missed ring NOT exactly at the predicted place!
So splitting rings without checking the sample, might sometimes be more of guessing than of good dendrochronology!
I propose that in cases like this, you should remove a sequence of badly measured rings and replace them by a group of zero rings.
Then it is later clearly visible that this is a problematic section.
If you have good arguments for changing CDendro on this point, then I might change my opinion on this!
/Lars-Åke