Click on the button: "Make block correlation analysis" We get the table shown above!
The "falsering.pos" sample has been divided into (overlapping) chunks of a lenght of 30 years.
These six blocks have all been separately correlated towards the reference.
Five of these blocks have a best match which would set the whole sample to relative year 120 or 119, i.e. 1875/76.
The block, covering rings between ring 20 and 50, contains (as we know) an incorrect extra ring so this block
does not match any good at its right place. Though there is another match for this block at relative year 1 meaning
that if it was a correct match, then the whole sample should date to year 2014. When this was originally written that was in the future...
Update Jan 16 2014:
Another way to find the 1875/76 match is to look at a line below a "SetsSampleTo alternatives..." line (see above) and look
for two adjacent years which will give you 1875 and 1876. At the last yellow marked line above this gives 2 blocks matching the reference so that the whole sample should match to 1875
and 3 blocks matching the reference so that the whole sample should match to 1876. I.e. a good chance that there is a false ring somewhere in the
middle of these 5 blocks. - You might also experiment with changing the blocklength from 30 to e.g. 40 or 50.
Still another way is to check "Extended block length test" before running the "Make block correlation analysis". This test is run exactly as the
test described above, but now when a block has been tested for a match it is then extended by 10 more years (=the length of the blockdistance)
and then again tested for a match, then again extended with 10 years etc. as long as the block can be extended within the sample.
I.e. we have successively growing blocks being tested for their best and next best matches.
In cases when you know that the sample is not younger than the reference, you can avoid
too young nonsense datings, by unchecking the box "Sample may be younger than the reference".
This holds for both whole sample correlation analysis and (from version 7.8) also for block correlation analysis!
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