| zakład ekologii populacyjnej | ::: | instytut | ::: | uniwersytet | ::: |  |
|
dr hab. Mariusz Cichoń
cichon@eko.uj.edu.pl |
Zakład Ekologii Populacyjnej Instytut Nauk o Środowisku Uniwersytet Jagielloński Gronostajowa 7, 30-387 Kraków Polska tel. + 48 12 664 52 01 fax + 48 12 664 69 12 |
||
home |
projekty |
+ publikacje |
dydaktyka |
Cichoń M., Merilä J., Hillström L., Wiggins D.
OIKOS
1999; 87 (1): 191-194
Abstrakt:
An assumption central to many tests of statistical association between two variables is the null-expectation of zero association. Here, we draw attention to the fact that in many published tests of mass-dependent mass loss in breeding birds, this assumption has been violated. We show that a correct null-hypothesis can be derived by using resampling methods, and analyse three data sets (two previously published) from passerine birds to illustrate the approach. Our results show, that under a correct null-hypothesis, the biological interpretation of the previously published results is reversed - initially heavy birds do actually loose less mass (relative to their weight) than the initially light birds.
d e s i g n e d b y P a w e ł K a p u s t a