Table 1.
Quantity | Maximum temperature | Minimum temperature | |||||
---|---|---|---|---|---|---|---|
Differencing | 2 point | 4 point | Differencing | 2 point | 4 point | ||
Q T (Heterogeneity) | 51·5 | 69·3 | 127·1 | 75·0 | 114·1 | 67·8 | |
d.f. | 36 | 36 | 36 | 37 | 37 | 37 | |
P‐value | 0·045 | <0·001 | <0·001 | <0·001 | <0·001 | 0·001 | |
|
0·0863 | 0·0900 | 0·0921 | 0·0497 | 0·0459 | 0·0476 | |
|
0·0058 | 0·0068 | 0·0081 | 0·0107 | 0·0126 | 0·0105 | |
σpooled | 0·0181 | 0·0262 | 0·0377 | 0·0441 | 0·0593 | 0·0418 | |
Square root of the mean within study variance | 0·0440 | 0·0419 | 0·0407 | 0·0595 | 0·0596 | 0·0622 | |
SE(r new) | 0·0190 | 0·0270 | 0·0385 | 0·0454 | 0·0606 | 0·0431 |
Q T is a measure for heterogeneity, calculated with eqn. 10. It is tested against a χ2 statistic with reported degrees of freedom and resulting P‐values. is the estimated mean relative rate of change of the catch per °C, calculated with eqns 6–8 (random‐effects model); is the standard error (= standard deviation) of , calculated with eqn. 9 for the random‐effects model taking the square root of the variance; SE(r new) calculated from eqn. 11 is the prediction error that measures the uncertainty of the r estimate for an entirely new study (r new).