Equal Datasets2

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The means of the datasets are as follows:

mean(Table.1.S6.A1.15kx$Wavelength)

[1] 727.1121

mean(Table.1.S6.A2.15kx$Wavelength)

[1] 737.3617

mean(Table.1.S6.A3.15kx.2$Wavelength)

[1] 749.1825

mean(Table.1.S9.A1.15kx$Wavelength)

[1] 618.723

mean(Table.1.S9.A2.15kx$Wavelength)

[1] 618.1679

mean(Table.1.S9.A3.15kx$Wavelength)

[1] 619.3731

Perform a paired t-test on the datasets:

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S6.A2.15kx$Wavelength, paired=TRUE)

    Paired t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S6.A2.15kx$Wavelength
t = -100.36, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 -10.44997 -10.04934
sample estimates:
mean difference 
      -10.24966 

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S6.A3.15kx.2$Wavelength, paired=TRUE)

    Paired t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S6.A3.15kx.2$Wavelength
t = -222.65, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 -22.26483 -21.87597
sample estimates:
mean difference 
       -22.0704 

t.test(Table.1.S6.A2.15kx$Wavelength, Table.1.S6.A3.15kx.2$Wavelength, paired=TRUE)

    Paired t-test

data:  Table.1.S6.A2.15kx$Wavelength and Table.1.S6.A3.15kx.2$Wavelength
t = -95.728, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 -12.06295 -11.57854
sample estimates:
mean difference 
      -11.82075 

t.test(Table.1.S9.A1.15kx$Wavelength, Table.1.S9.A2.15kx$Wavelength, paired=TRUE)

    Paired t-test

data:  Table.1.S9.A1.15kx$Wavelength and Table.1.S9.A2.15kx$Wavelength
t = 9.596, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 0.4416444 0.6685757
sample estimates:
mean difference 
      0.5551101 

t.test(Table.1.S9.A1.15kx$Wavelength, Table.1.S9.A3.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S9.A1.15kx$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = -11.103, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 -0.7649469 -0.5352556
sample estimates:
mean difference 
     -0.6501012 

t.test(Table.1.S9.A2.15kx$Wavelength, Table.1.S9.A3.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S9.A2.15kx$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = -26.192, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 -1.295467 -1.114955
sample estimates:
mean difference 
      -1.205211 

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S9.A1.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S9.A1.15kx$Wavelength
t = 1572.8, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 108.2539 108.5243
sample estimates:
mean difference 
       108.3891 

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S9.A2.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S9.A2.15kx$Wavelength
t = 1777.6, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 108.8240 109.0644
sample estimates:
mean difference 
       108.9442 

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S9.A3.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = 1878.4, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 107.6265 107.8515
sample estimates:
mean difference 
        107.739 

t.test(Table.1.S6.A2.15kx$Wavelength, Table.1.S9.A1.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S6.A2.15kx$Wavelength and Table.1.S9.A1.15kx$Wavelength
t = 1186.3, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 118.4426 118.8349
sample estimates:
mean difference 
       118.6388 

t.test(Table.1.S6.A2.15kx$Wavelength, Table.1.S9.A2.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S6.A2.15kx$Wavelength and Table.1.S9.A2.15kx$Wavelength
t = 1256.8, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 119.0078 119.3799
sample estimates:
mean difference 
       119.1939 

t.test(Table.1.S6.A2.15kx$Wavelength, Table.1.S9.A3.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S6.A2.15kx$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = 1302.8, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 117.8110 118.1663
sample estimates:
mean difference 
       117.9886 

t.test(Table.1.S6.A3.15kx.2$Wavelength, Table.1.S9.A1.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S6.A3.15kx.2$Wavelength and Table.1.S9.A1.15kx$Wavelength
t = 1337.3, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 130.2681 130.6508
sample estimates:
mean difference 
       130.4595 

t.test(Table.1.S6.A3.15kx.2$Wavelength, Table.1.S9.A2.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S6.A3.15kx.2$Wavelength and Table.1.S9.A2.15kx$Wavelength
t = 1415.8, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 130.8331 131.1961
sample estimates:
mean difference 
       131.0146 

t.test(Table.1.S6.A3.15kx.2$Wavelength, Table.1.S9.A3.15kx$Wavelength, paired = TRUE)

    Paired t-test

data:  Table.1.S6.A3.15kx.2$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = 1463, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 129.6354 129.9834
sample estimates:
mean difference 
       129.8094 

Investigate if the variances are equal:

var(Table.1.S6.A1.15kx$Wavelength)

[1] 4.050206

var(Table.1.S6.A2.15kx$Wavelength)

[1] 12.23319

var(Table.1.S6.A3.15kx.2$Wavelength)

[1] 11.6465

var(Table.1.S9.A1.15kx$Wavelength)

[1] 3.81173

var(Table.1.S9.A2.15kx$Wavelength)

[1] 2.256774

var(Table.1.S9.A3.15kx$Wavelength)

[1] 1.36843

Perform a Welch t-test (unequal variances) on the datasets:

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S6.A2.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S6.A2.15kx$Wavelength
t = -101.6, df = 2553.2, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 -10.44747 -10.05184
sample estimates:
mean of x mean of y 
 727.1121  737.3617 

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S6.A3.15kx.2$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S6.A3.15kx.2$Wavelength
t = -222.83, df = 2591.2, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 -22.26462 -21.87618
sample estimates:
mean of x mean of y 
 727.1121  749.1825 

t.test(Table.1.S6.A2.15kx$Wavelength, Table.1.S6.A3.15kx.2$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A2.15kx$Wavelength and Table.1.S6.A3.15kx.2$Wavelength
t = -96.759, df = 3196.1, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 -12.06028 -11.58121
sample estimates:
mean of x mean of y 
 737.3617  749.1825 

t.test(Table.1.S9.A1.15kx$Wavelength, Table.1.S9.A2.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S9.A1.15kx$Wavelength and Table.1.S9.A2.15kx$Wavelength
t = 9.0136, df = 3001, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 0.4343553 0.6758648
sample estimates:
mean of x mean of y 
 618.7230  618.1679 

t.test(Table.1.S9.A1.15kx$Wavelength, Table.1.S9.A3.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S9.A1.15kx$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = -11.425, df = 2616, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 -0.7616746 -0.5385278
sample estimates:
mean of x mean of y 
 618.7230  619.3731 

t.test(Table.1.S9.A2.15kx$Wavelength, Table.1.S9.A3.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S9.A2.15kx$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = -25.32, df = 3016.8, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 -1.298543 -1.111880
sample estimates:
mean of x mean of y 
 618.1679  619.3731 

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S9.A1.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S9.A1.15kx$Wavelength
t = 1546.3, df = 3195.1, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 108.2517 108.5265
sample estimates:
mean of x mean of y 
 727.1121  618.7230 

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S9.A2.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S9.A2.15kx$Wavelength
t = 1735.2, df = 2958.8, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 108.8211 109.0673
sample estimates:
mean of x mean of y 
 727.1121  618.1679 

t.test(Table.1.S6.A1.15kx$Wavelength, Table.1.S9.A3.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A1.15kx$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = 1851.3, df = 2568.8, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 107.6249 107.8531
sample estimates:
mean of x mean of y 
 727.1121  619.3731 

t.test(Table.1.S6.A2.15kx$Wavelength, Table.1.S9.A1.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A2.15kx$Wavelength and Table.1.S9.A1.15kx$Wavelength
t = 1184.7, df = 2507.3, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 118.4424 118.8351
sample estimates:
mean of x mean of y 
 737.3617  618.7230 

t.test(Table.1.S6.A2.15kx$Wavelength, Table.1.S9.A2.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A2.15kx$Wavelength and Table.1.S9.A2.15kx$Wavelength
t = 1252.5, df = 2169.5, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 119.0072 119.3805
sample estimates:
mean of x mean of y 
 737.3617  618.1679 

t.test(Table.1.S6.A2.15kx$Wavelength, Table.1.S9.A3.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A2.15kx$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = 1279.7, df = 1952.3, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 117.8078 118.1695
sample estimates:
mean of x mean of y 
 737.3617  619.3731 

t.test(Table.1.S6.A3.15kx.2$Wavelength, Table.1.S9.A1.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A3.15kx.2$Wavelength and Table.1.S9.A1.15kx$Wavelength
t = 1327.3, df = 2544.4, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 130.2668 130.6522
sample estimates:
mean of x mean of y 
 749.1825  618.7230 

t.test(Table.1.S6.A3.15kx.2$Wavelength, Table.1.S9.A2.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A3.15kx.2$Wavelength and Table.1.S9.A2.15kx$Wavelength
t = 1405.5, df = 2196.3, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 130.8318 131.1974
sample estimates:
mean of x mean of y 
 749.1825  618.1679 

t.test(Table.1.S6.A3.15kx.2$Wavelength, Table.1.S9.A3.15kx$Wavelength)

    Welch Two Sample t-test

data:  Table.1.S6.A3.15kx.2$Wavelength and Table.1.S9.A3.15kx$Wavelength
t = 1439.3, df = 1969.6, p-value < 2.2e-16
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 129.6325 129.9863
sample estimates:
mean of x mean of y 
 749.1825  619.3731 

Histograms (distribution)

hist(Table.1.S6.A3.15kx.2$Wavelength)

hist(Table.1.S9.A1.15kx$Wavelength)

hist(Table.1.S9.A2.15kx$Wavelength)

hist(Table.1.S9.A3.15kx$Wavelength)

Boxplots and outliers:

S6A1boxwl =boxplot(Table.1.S6.A1.15kx$Wavelength, main = "S6A1 WL Boxplot")

S6A1boxwl$out

 [1] 717.5747 722.1169 718.0609 718.8560 722.4953 732.0764 722.4573 722.8478 721.9830
[10] 722.7003 720.9149 722.8628 722.7427 719.5100 717.9786 719.6526 715.6333 723.0511
[19] 722.2962 722.3333 721.9185 719.8494 722.8971 717.7820 719.4545 721.7669 717.4575
[28] 722.9838 722.8704 721.2166 722.8829 722.6329 721.7331 722.5729 717.6791 721.6863
[37] 720.4176 722.9317 722.8374 722.8712 719.6393 721.7645 720.8510 722.6573 722.8381
[46] 717.8647 720.9788 722.2167 722.4506 722.6434 720.3706 719.9757 722.0039 721.7328
[55] 722.8626 722.7079 723.0320 717.8429 714.0798 711.8063 722.1324 722.4533 731.6285
[64] 720.4701 731.6689 715.5001

S6A2boxwl =boxplot(Table.1.S6.A2.15kx$Wavelength, main = "S6A2 WL Boxplot")

S6A2boxwl$out

 [1] 725.9287 717.6291 730.1907 725.1105 726.2572 730.9071 729.4615 730.6012 722.7515
[10] 727.8723 729.2561 724.0540 729.8050 726.0229 729.3732 723.5545 727.6802 744.0139
[19] 743.8884 727.5576 729.3242 720.0817 730.2447 725.6782 718.0536 721.8363 730.3834
[28] 723.5190 719.4860 728.2634 726.8415 724.0789 712.8082 724.8851 719.4628 730.2681
[37] 725.8364 723.1948 713.2479 720.6766 719.2429 720.2332 730.0846 729.2472 722.6358
[46] 727.8714 724.8862 730.8769 723.8488 725.7876 720.2925 731.7409 724.7313 729.7973
[55] 720.0462 729.6516 731.6176 729.1431 719.2657 726.6464 729.9947 728.3057 722.8027
[64] 729.8483 730.2066 716.6324 723.7471 727.9779 718.0091 730.6107 729.4838 722.4206
[73] 726.2883 722.5788 716.7606

S6A3boxwl =boxplot(Table.1.S6.A3.15kx.2$Wavelength, main = "S6A3 WL Boxplot")

S6A3boxwl$out

 [1] 756.3054 754.1490 755.5833 754.3731 713.6424 713.5269 754.0612 754.7085 715.6357
[10] 719.7299 754.1067 754.3983 719.9301 703.8573 691.5620 716.7122 754.7199 753.9919
[19] 754.5764 754.3456 718.8609 754.6517 713.4872

S9A1boxwl =boxplot(Table.1.S9.A1.15kx$Wavelength, main = "S9A1 WL Boxplot")

S9A1boxwl$out

 [1] 614.3907 613.8526 612.8803 610.3163 614.7678 612.5549 613.3233 615.2516 612.7104
[10] 615.0293 609.4084 614.4168 609.8772 611.6763 611.6345 612.6258 612.0496 612.5514
[19] 615.3330 614.7787 614.5202 613.4426 614.3354 613.8319 608.6236 615.3308 610.0928
[28] 613.8137 611.8370 613.6791 614.5113 614.5260 606.1351 614.7310 615.1954 612.3110
[37] 615.0628 614.8400 615.3173 614.4593 612.4740 596.1660 614.5922 615.2111 615.1068
[46] 599.5875 614.5750 611.5685 614.1545 608.7160 611.5228 612.8839 608.3000 614.0835
[55] 615.2604 612.7058 614.0035 608.8464 615.2073 612.9156 607.8673 614.5320 605.0079
[64] 613.7451 615.3106 615.2796 612.9546 610.5039

S9A2boxwl =boxplot(Table.1.S9.A2.15kx$Wavelength, main = "S9A2 WL Boxplot")

S9A2boxwl$out

 [1] 613.4274 614.2328 613.2524 613.3108 614.7886 613.7304 614.4655 613.1110 614.4837
[10] 614.6514 613.3747 614.2186 613.9522 612.6071 613.9811 614.7655 612.2796 613.1126
[19] 613.9255 611.5269 613.4128 611.5552 614.6186 614.3516 607.5781 613.1305 613.0303
[28] 614.8059 609.9020 614.5574 610.4207 613.6740 614.7595 614.6296 614.7362 613.5770
[37] 614.4376 614.7827 613.4767 609.0284 614.0826 613.8425 613.5616 614.1100 614.5838
[46] 613.9657 613.9097 613.5520 613.7362 614.5675 614.5230 614.7935 614.1043

S9A3boxwl =boxplot(Table.1.S9.A3.15kx$Wavelength, main = "S9A3 WL Boxplot")

S9A3boxwl$out

 [1] 615.1440 615.8734 615.7891 614.5813 616.3048 615.5097 616.2532 615.8263 613.9662
[10] 615.8332 615.3695 615.7636 616.5325 616.1044 616.0406 616.3155 616.2708 614.7139
[19] 615.6746 616.2497 616.5409 615.0777 616.3429 615.4699 615.3313 616.5978 616.4805
[28] 613.2217 613.6386 615.4745 616.5145 616.1732 616.5626 616.5641 616.5295 622.6617
[37] 622.4189 616.6082 616.2798 623.4345 622.5024

Consider the datasets S6 A1-A3:

The means of the datasets are as follows:

mean(S6.A1.15kx.Table.1$Wavelength)

[1] 708.881

mean(S6.A2.15kx.Table.1$Wavelength)

[1] 744.0974

mean(S6.A3.15kx.Table.1$Wavelength)

[1] 749.1825

mean(S6.A3.500.1000.Table.1$Wavelength)

[1] 751.4443

Variances:

var(S6.A1.15kx.Table.1$Wavelength)

[1] 4.17989

var(S6.A2.15kx.Table.1$Wavelength)

[1] 20.3156

var(S6.A3.15kx.Table.1$Wavelength)

[1] 11.6465

var(S6.A3.500.1000.Table.1$Wavelength)

[1] 1.70879

Pairwise t-test:

t.test(S6.A1.15kx.Table.1$Wavelength, S6.A2.15kx.Table.1$Wavelength, paired=TRUE)

    Paired t-test

data:  S6.A1.15kx.Table.1$Wavelength and S6.A2.15kx.Table.1$Wavelength
t = -294.01, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 -35.45136 -34.98147
sample estimates:
mean difference 
      -35.21641 

t.test(S6.A1.15kx.Table.1$Wavelength, S6.A3.15kx.Table.1$Wavelength, paired=TRUE)

    Paired t-test

data:  S6.A1.15kx.Table.1$Wavelength and S6.A3.15kx.Table.1$Wavelength
t = -419.54, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 -40.48995 -40.11311
sample estimates:
mean difference 
      -40.30153 

#t.test(S6.A1.15kx.Table.1$Wavelength, S6.A3.500.1000.Table.1$Wavelength, paired=TRUE)
t.test(S6.A2.15kx.Table.1$Wavelength, S6.A3.15kx.Table.1$Wavelength, paired=TRUE)

    Paired t-test

data:  S6.A2.15kx.Table.1$Wavelength and S6.A3.15kx.Table.1$Wavelength
t = -37.513, df = 1599, p-value < 2.2e-16
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 -5.351001 -4.819230
sample estimates:
mean difference 
      -5.085116 

#t.test(S6.A2.15kx.Table.1$Wavelength, S6.A3.500.1000.Table.1$Wavelength, paired=TRUE)
#t.test(S6.A3.15kx.Table.1$Wavelength, S6.A3.500.1000.Table.1$Wavelength, paired=TRUE)

Take samples of S6A1, S6A2, S6A3, to perform a t-test with S6A3.500 which only has 900 observaions.

#S6.A1WL=as.integer(S6.A1.15kx.Table.1$Wavelength)
#SampleS6A1 = sample(1:1600, 900)
#S6.A2WL=as.integer(S6.A2.15kx.Table.1$Wavelength)
#SampleS6A2 = sample(1:1600, 900)
S6.A3WL=as.integer(S6.A3.15kx.Table.1$Wavelength)
SampleS6A3 = sample(1:1600, 900)

Welch t-test (because variances are not equal):

#t.test(S6.A1.15kx.Table.1$Wavelength, S6.A2.15kx.Table.1$Wavelength, var.equal=FALSE)
#t.test(S6.A1.15kx.Table.1$Wavelength, S6.A3.15kx.Table.1$Wavelength, var.equal = FALSE)

#t.test(SampleS6A1, S6.A3.500.1000.Table.1$Wavelength, paired=TRUE)
#t.test(SampleS6A2, S6.A3.500.1000.Table.1$Wavelength, paired=TRUE)
t.test(SampleS6A3, S6.A3.500.1000.Table.1$Wavelength, paired=TRUE)

    Paired t-test

data:  SampleS6A3 and S6.A3.500.1000.Table.1$Wavelength
t = 3.5694, df = 899, p-value = 0.0003767
alternative hypothesis: true mean difference is not equal to 0
95 percent confidence interval:
 24.56795 84.58348
sample estimates:
mean difference 
       54.57572 

t.test(SampleS6A3, S6.A3.500.1000.Table.1$Wavelength, var.equal = FALSE)

    Welch Two Sample t-test

data:  SampleS6A3 and S6.A3.500.1000.Table.1$Wavelength
t = 3.5689, df = 899.01, p-value = 0.0003775
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
 24.56308 84.58836
sample estimates:
mean of x mean of y 
 806.0200  751.4443 

#t.test(S6.A3.15kx.Table.1$Wavelength, S6.A3.500.1000.Table.1$Wavelength, paired=TRUE)