Geoscience Reference
In-Depth Information
h e data show a preferred direction if the calculated mean resultant length is
below the critical value (Mardia 1972). As an example we again load the data
contained in the i le
directional_1.txt
.
clear
data_degrees_1 = load('directional_1.txt');
data_radians_1 = pi*data_degrees_1/180;
We then calculate the mean resultant vector
Rm
.
Table 10.1
Critical values of mean resultant length for Rayleigh's test for the signii cance of a
mean direction of
N
samples (Mardia 1972).
Level of Signii cance, ʱ
N
0.100
0.050
0.025
0.010
0.001
5
0.677
0.754
0.816
0.879
0.991
6
0.618
0.690
0.753
0.825
0.940
7
0.572
0.642
0.702
0.771
0.891
8
0.535
0.602
0.660
0.725
0.847
9
0.504
0.569
0.624
0.687
0.808
10
0.478
0.540
0.594
0.655
0.775
11
0.456
0.516
0.567
0.627
0.743
12
0.437
0.494
0.544
0.602
0.716
13
0.420
0.475
0.524
0.580
0.692
14
0.405
0.458
0.505
0.560
0.669
15
0.391
0.443
0.489
0.542
0.649
16
0.379
0.429
0.474
0.525
0.630
17
0.367
0.417
0.460
0.510
0.613
18
0.357
0.405
0.447
0.496
0.597
19
0.348
0.394
0.436
0.484
0.583
20
0.339
0.385
0.425
0.472
0.569
21
0.331
0.375
0.415
0.461
0.556
22
0.323
0.367
0.405
0.451
0.544
23
0.316
0.359
0.397
0.441
0.533
24
0.309
0.351
0.389
0.432
0.522
25
0.303
0.344
0.381
0.423
0.512
30
0.277
0.315
0.348
0.387
0.470
35
0.256
0.292
0.323
0.359
0.436
40
0.240
0.273
0.302
0.336
0.409
45
0.226
0.257
0.285
0.318
0.386
50
0.214
0.244
0.270
0.301
0.367
100
0.150
0.170
0.190
0.210
0.260