Student's "t" Table
This menu item provides a listing for typical confidence levels of Student's "t" values. William Gossett (1876-1937) worked for the Guinness Brewing Company on quality control issues. He developed a number of statistical tools for situations where it was not always feasible to measure a large enough number of replicate samples. Student's "t" or test table is one of these. He was not allowed to use his own name so he published then under the name "Student". These values are used in many statistical calculations to this day. See Calculate Detection Limits and Homogeneity above for an example of this parameter in use.
The following is the printout from the Student's "t" table menu, where # pts is the number of data points, d.f. is the "degrees of freedom", 0.60 to 0.99 is the probability confidence level.:
# pts d.f. 0.60 0.80 0.90 0.95 0.99
2 1 1.3764 3.0777 6.3138 12.7062 63.6567
3 2 1.0607 1.8856 2.9200 4.3027 9.9248
4 3 .9785 1.6377 2.3534 3.1824 5.8409
5 4 .9410 1.5332 2.1318 2.7764 4.6041
6 5 .9195 1.4759 2.0151 2.5706 4.0321
7 6 .9057 1.4398 1.9432 2.4469 3.7074
8 7 .8961 1.4149 1.8946 2.3646 3.4995
9 8 .8889 1.3968 1.8595 2.3061 3.3554
10 9 .8834 1.3831 1.8331 2.2622 3.2498
11 10 .8791 1.3722 1.8125 2.2281 3.1693
12 11 .8755 1.3634 1.7959 2.2010 3.1058
13 12 .8726 1.3562 1.7823 2.1788 3.0545
14 13 .8702 1.3502 1.7709 2.1604 3.0123
15 14 .8681 1.3451 1.7613 2.1448 2.9768
16 15 .8662 1.3406 1.7531 2.1314 2.9467
17 16 .8647 1.3368 1.7459 2.1199 2.9208
18 17 .8633 1.3334 1.7396 2.1098 2.8982
19 18 .8621 1.3304 1.7341 2.1009 2.8784
20 19 .8610 1.3277 1.7291 2.0931 2.8609
21 20 .8600 1.3253 1.7247 2.0860 2.8453
22 21 .8591 1.3232 1.7207 2.0796 2.8314
23 22 .8583 1.3212 1.7171 2.0739 2.8188
24 23 .8575 1.3195 1.7139 2.0687 2.8073
25 24 .8569 1.3178 1.7109 2.0639 2.7969
26 25 .8562 1.3163 1.7081 2.0595 2.7874
27 26 .8557 1.3150 1.7056 2.0555 2.7787
28 27 .8551 1.3137 1.7033 2.0518 2.7707
29 28 .8546 1.3125 1.7011 2.0484 2.7633
30 29 .8542 1.3114 1.6991 2.0452 2.7564
31 30 .8538 1.3104 1.6973 2.0423 2.7500
32 31 .8534 1.3095 1.6955 2.0395 2.7441
33 32 .8530 1.3086 1.6939 2.0369 2.7385
34 33 .8526 1.3077 1.6924 2.0345 2.7333
35 34 .8523 1.3069 1.6909 2.0322 2.7284
36 35 .8521 1.3062 1.6896 2.0301 2.7238
37 36 .8517 1.3055 1.6883 2.0281 2.7195
38 37 .8514 1.3049 1.6871 2.0262 2.7154
39 38 .8512 1.3042 1.6860 2.0244 2.7116
40 39 .8509 1.3036 1.6849 2.0227 2.7079
41 40 .8507 1.3031 1.6839 2.0211 2.7045
42 41 .8505 1.3025 1.6829 2.0195 2.7012
43 42 .8503 1.3021 1.6820 2.0181 2.6981
44 43 .8501 1.3016 1.6811 2.0167 2.6951
45 44 .8499 1.3011 1.6802 2.0154 2.6923
46 45 .8497 1.3007 1.6794 2.0141 2.6896
47 46 .8495 1.3002 1.6787 2.0129 2.6871
48 47 .8493 1.2998 1.6779 2.0117 2.6846
49 48 .8492 1.2994 1.6772 2.0106 2.6822
50 49 .8491 1.2991 1.6766 2.0096 2.6800