Statistical Tables
Table E.2 Proportions of area for the t distributions
261
Proportions of Area
for the t Distributions
Areas reported below:
Proportion of
(one tail)
df 0.10
0.05 0.025 0.01 0.005
df 0.10 0.05 0.025 0.01 0.005
1 3.078 6.314 12.706 31.821 63.657 18 1.330 1.734 2.101 2.552 2.878
2 1.886 2.920 4.303 6.965 9.925 19 1.328 1.729 2.093 2.539 2.861
3 1.638 2.353 3.182 4.541 5.841 20 1.325 1.725 2.086 2.528 2.845
4 1.533 2.132 2.776 3.747 4.604 21 1.323 1.721 2.080 2.518 2.831
5 1.476 2.015 2.571 3.365 4.032 22 1.321 1.717 2.074 2.508 2.819
6 1.440 1.943 2.447 3.143 3.707 23 1.319 1.714 2.069 2.500 2.807
7 1.415 1.895 2.365 2.998 3.499 24 1.318 1.711 2.064 2.492 2.797
8 1.397 1.860 2.306 2.896 3.355 25 1.316 1.708 2.060 2.485 2.787
9 1.383 1.833 2.262 2.821 3.250 26 1.315 1.706 2.056 2.479 2.779
10 1.372 1.812 2.228 2.764 3.169 27 1.314 1.703 2.052 2.473 2.771
11 1.363 1.796 2.201 2.718 3.106 28 1.313 1.701 2.048 2.467 2.763
12 1.356 1.782 2.179 2.681 3.055 29 1.311 1.699 2.045 2.462 2.756
13 1.350 1.771 2.160 2.650 3.012 30 1.310 1.697 2.042 2.457 2.750
14 1.345 1.761 2.145 2.624 2.977 40 1.303 1.684 2.021 2.423 2.704
15 1.341 1.753 2.131 2.602 2.947 60 1.296 1.671 2.000 2.390 2.660
16 1.337 1.746 2.120 2.583 2.921 120 1.289 1.658 1.980 2.358 2.617
17 1.333 1.740 2.110 2.567 2.898
~ 1.282 1.645 1.960 2.326 2.576
* Example. For the shaded area to represent 0.05 of the total area of 1.0, value of t with 10
degrees of freedom is 1.812.
Source: From Table III of Fisher and Yates, Statistical Tables for Biological Agricultural and
Medical Research, 6th ed., 1974, published by Longman Group Ltd., London (previously published by Oliver and Boyd, Edinburgh), by permission of the authors and publishers.
Table E.2 Proportions of area for the t distributions
261
Proportions of Area
for the t Distributions
Areas reported below:
Proportion of
(one tail)
df 0.10
0.05 0.025 0.01 0.005
df 0.10 0.05 0.025 0.01 0.005
1 3.078 6.314 12.706 31.821 63.657 18 1.330 1.734 2.101 2.552 2.878
2 1.886 2.920 4.303 6.965 9.925 19 1.328 1.729 2.093 2.539 2.861
3 1.638 2.353 3.182 4.541 5.841 20 1.325 1.725 2.086 2.528 2.845
4 1.533 2.132 2.776 3.747 4.604 21 1.323 1.721 2.080 2.518 2.831
5 1.476 2.015 2.571 3.365 4.032 22 1.321 1.717 2.074 2.508 2.819
6 1.440 1.943 2.447 3.143 3.707 23 1.319 1.714 2.069 2.500 2.807
7 1.415 1.895 2.365 2.998 3.499 24 1.318 1.711 2.064 2.492 2.797
8 1.397 1.860 2.306 2.896 3.355 25 1.316 1.708 2.060 2.485 2.787
9 1.383 1.833 2.262 2.821 3.250 26 1.315 1.706 2.056 2.479 2.779
10 1.372 1.812 2.228 2.764 3.169 27 1.314 1.703 2.052 2.473 2.771
11 1.363 1.796 2.201 2.718 3.106 28 1.313 1.701 2.048 2.467 2.763
12 1.356 1.782 2.179 2.681 3.055 29 1.311 1.699 2.045 2.462 2.756
13 1.350 1.771 2.160 2.650 3.012 30 1.310 1.697 2.042 2.457 2.750
14 1.345 1.761 2.145 2.624 2.977 40 1.303 1.684 2.021 2.423 2.704
15 1.341 1.753 2.131 2.602 2.947 60 1.296 1.671 2.000 2.390 2.660
16 1.337 1.746 2.120 2.583 2.921 120 1.289 1.658 1.980 2.358 2.617
17 1.333 1.740 2.110 2.567 2.898
~ 1.282 1.645 1.960 2.326 2.576
* Example. For the shaded area to represent 0.05 of the total area of 1.0, value of t with 10
degrees of freedom is 1.812.
Source: From Table III of Fisher and Yates, Statistical Tables for Biological Agricultural and
Medical Research, 6th ed., 1974, published by Longman Group Ltd., London (previously published by Oliver and Boyd, Edinburgh), by permission of the authors and publishers.