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Table 1 Relationships between prey length or prey length grouping and characteristics of true-positive detections

From: Head-mounted accelerometry accurately detects prey capture in California sea lions

Sampling rate Test DF Prey capture duration Max. heave Jerk Max. surge deceleration Heave Jerk integral Surge accel. integral
p R2 p R2 p R2 p R2 p R2
CALI
 333 Hz Lin. Reg 54  < 0.0001* 0.254 0.214 0.029 0.098 0.051 0.0003* 0.221  < 0.0001* 0.346
  T-test 53  < 0.0001*   0.419   0.334   0.008*    < 0.0001*  
 200 Hz Lin. Reg 54  < 0.0003* 0.226 0.351 0.016 0.079 0.057  < 0.0001* 0.271  < 0.0001* 0.399
  T-test 53  < 0.0001*   0.648   0.294   0.002*    < 0.0001*  
 100 Hz Lin. Reg 55  < 0.0001* 0.284 0.487 0.009 0.056 0.066  < 0.0001* 0.269  < 0.0001* 0.435
  T-test 54  < 0.0001*   0.772   0.253   0.003*    < 0.0001*  
 50 Hz Lin. Reg 54  < 0.0001* 0.357 0.224 0.028 0.221 0.028  < 0.0001* 0.28  < 0.0001* 0.482
  T-test 53  < 0.0001*   0.660   0.348   0.004*    < 0.0001*  
 32 Hz Lin. Reg 50  < 0.0001* 0.314 0.292 0.025 0.275 0.024 0.002* 0.18 0.0004* 0.225
  T-test 49  < 0.0001*   0.938   0.695   0.019*   0.012*  
 20 Hz Lin. Reg 34 0.243 0.041 0.372 0.024 0.89  < 0.001 0.026* 0.142 0.027* 0.14
  T-test 33 0.108   0.609   0.756   0.016*   0.002*  
 16 Hz Lin. Reg 25 0.157 0.082 0.416 0.028 0.667 0.008 0.005* 0.285 0.006* 0.277
  T-test 24 0.316   0.155   0.994   0.004*   0.013*  
NEMO
 333 Hz Lin. Reg 41 0.098 0.067 0.841 0.001 0.151 0.051 0.084 0.073 0.111 0.062
  T-test 40 0.018*   0.837   0.066   0.079   0.097  
 200 Hz Lin. Reg 43 0.108 0.06 0.774 0.002 0.113 0.059 0.044* 0.093 0.078 0.072
  T-test 42 0.036*   0.924   0.062   0.095   0.123  
 100 Hz Lin. Reg 43 0.087 0.068 0.838 0.001 0.114 0.059 0.049* 0.089 0.049* 0.089
  T-test 42 0.028*   0.949   0.079   0.125   0.086  
 50 Hz Lin. Reg 38 0.234 0.038 0.387 0.02 0.2 0.044 0.165 0.051 0.244 0.037
  T-test(W) 37(26) 0.090   0.294   0.039*   0.141   0.144  
 32 Hz Lin. Reg 18 0.105 0.147 0.36 0.05 0.64 0.013 0.169 0.108 0.238 0.081
  T-test 17 0.014*   0.905   0.312   0.208   0.166  
 20 Hz Lin. Reg 17 0.619 0.016 0.528 0.025 0.06 0.205 0.697 0.009 0.791 0.005
  T-test (W) 16(10) 0.026*   0.151   0.192   0.069   0.196  
 16 Hz Lin. Reg 7 0.386 0.127 0.127 0.343 0.782 0.014 0.364 0.139 0.936 0.001
  T-test 6 0.335   0.186   0.732   0.734   0.881  
  1. Lin. Reg. indicates simple linear regressions. T-test refers to 2-sample Student’s t-tests assuming equal variance, comparing among large and small prey length groupings. T-test(W) indicates that Welch’s t-tests were used when variance was unequal among large and small prey length grouping. Df numbers in parentheses are degrees of freedom in Welch’s t-tests. Df varies with sampling rate within individual because only data from true-positive detections were included in statistical analyses. T-test df = (n−2) and Lin. Reg. df = (n−1)
  2. Bold, italicized font and the * symbol denotes either a significant relationship (Lin. Reg.) or a significant difference among prey length group (T-test or T-test(W))