T-values

The correlation between the tree-ring curves from the measured boards and diverse oak chronologies and datasets from Northern Europe is calculated using the Student’s t-test (t-value). Generally, t-values over 3.5 should be considered significant, although in reality it is common to find demonstrably spurious t-values of 4 and 5 because more than one matching position is indicated. This is why dendrochronologists prefer some t-value ranges of 5, 6, or higher, and for these to be well replicated using different, independent chronologies and with both local and regional chronologies being well represented. The validity of dates must also be critically assessed. A date supported by a handful of t-values of 3 and one or two of 4 cannot be fully relied upon, nor should a single high match of 5 or 6 suffice. Examples of spurious t-values in excess of 7 have been noted, so it is essential that matches with reference chronologies be well replicated, and that these are confirmed using visual matches between the two graphs. Matches with t-values of 10 or more between individual sequences usually means the samples originated from the same parent tree (Miles, 2010).

Filenames	-	-	board 1 upper Z1440019	board 2 lower Z144002a
-	start	dates	AD1455	AD1537
-	dates	end	AD1562	AD1608
DM200006	AD914	AD1873	3,41	7,22	Lüneburger Heide (Hamburg Uni.)
H115YF01	AD1433	AD1649	3,52	7,01	Moelln Marktstr. + Haupfts. 11 timbers (Hamburg Uni revised Daly 2007)
HO32VM02	AD1474	AD1672	3,73	6,90	Zarrentin Kirche 18 timbers (Hamburg Uni revised Daly 2007)
DM200005	AD915	AD1873	3,83	6,48	Niedersachsen; Nord (Hamburg Uni )
G370HZ01	AD1426	AD1617	4,28	6,08	Oldenburg 31 timbers (Göttingen Uni revised Daly 2007)
G342LZ01	AD1410	AD1607	-	6,30	Wolfenbüttel 8 timbers (Göttingen Uni revised Daly 2007)
G352YZ01	AD1509	AD1699	-	6,18	Dreilingen 3 timbers (Göttingen Uni revised Daly 2007)
H11J9M01	AD1506	AD1632	-	6,05	Lübeck Engelswisch 4 timbers (Hamburg Uni revised Daly 2007)
H114FM01	AD1519	AD1650	-	5,82	Kankelau Talkauerw 4 timbers (Hamburg Uni revised Daly 2007)
G3511Z01	AD1406	AD1575	-	5,77	Lüneburg 6 timbers (Göttingen Uni revised Daly 2007)
G370YZ01	AD1510	AD1654	-	5,57	Jork 4 timbers (Göttingen Uni revised Daly 2007)
G351BZ01	AD1533	AD1643	\	5,54	Lüneburg 2 timbers (Göttingen Uni revised Daly 2007)
G340QZ01	AD1536	AD1724	\	5,50	Braunschweig 10 timbers (Göttingen Uni revised Daly 2007)
DM100007	AD1080	AD1967	5,69	6,36	Hamburg (Hamburg Uni )
H115JM01	AD1405	AD1530	8,15	\	Daldorf Dorfstr. 4 timbers (Hamburg Uni revised Daly 2007)
H115BM01	AD1461	AD1553	7,76	\	Sierksrade 2 timbers (Hamburg Uni revised Daly 2007)
Z108M001	AD1402	AD1577	7,37	-	Cuxhaven Ship group1 3 timbers (Daly 2014)
H116AM02	AD1394	AD1575	7,79	-	Kl. Nuetschau Herr 16 timbers (Hamburg Uni revised Daly 2007)
H1177M01	AD1424	AD1585	7,35	-	Preetz Klosterh. 19. 8 timbers (Hamburg Uni revised Daly 2007)
H1156M01	AD1439	AD1619	7,28	-	Toenningstedt 5 timbers (Hamburg Uni revised Daly 2007)
H1178M01	AD1397	AD1624	7,17	3,94	Preetz Thiemenhaus + Klosterhof 19 timbers (Hamburg Uni revised Daly 2007)
H11I8M01	AD1426	AD1549	6,94	\	Lübeck Hartengrube 4 timbers (Hamburg Uni revised Daly 2007)
H11KLM01	AD1385	AD1589	6,75	-	Lübeck Mengstr. 18 timbers (Hamburg Uni revised Daly 2007)
DM100006	AD1330	AD1650	6,20	4,74	Luebeck (Hamburg Uni.)
H1149M01	AD1432	AD1600	6,06	-	Klein Gr\Nau 9 timbers (Hamburg Uni revised Daly 2007)
H11HPM01	AD1406	AD1608	5,96	3,18	Lübeck Heiliggeist-Hos 3 timbers (Hamburg Uni revised Daly 2007)
H11GIM01	AD1387	AD1556	5,88	\	Lübeck Burgtor/Zoellnerh 4 timbers (Hamburg Uni revised Daly 2007)
H200OM01	AD1399	AD1552	5,84	\	Hbg. Reimerstwiete 3 timbers (Hamburg Uni revised Daly 2007)
Z093M001	AD1420	AD1614	5,76	3,37	Vasa barrels 7 timbers (Daly 2013)
H1179M01	AD1454	AD1618	5,66	5,13	Moelln Hauptstr. 6 timbers (Hamburg Uni revised Daly 2007)

Table 1. Example of t-values from a measurement of Anthonie Palamedesz (attr.), A Guardroom, KMSsp412. Results of the correlation (t-value) between the tree-ring curves from the two boards (Z1440019 & Z144002a) and diverse tree-ring chronologies. The source of the chronologies is given. The grey tone highlights the high t-values.

Dendrochronology