Descriptions of the Tables
(References to appropriate books or articles are given for the less familiar topics.)
Section 1: Discrete Probability Distributions
The quantity tabulated in Table 1.1 (pp 20â26) is the cdf (cumulative distribution function) of the binomial distribution:
which is the probability of obtaining
x or less âsuccessesâ in
n independent trials of an experiment where at each trial the probability of success is
p. Individual probabilities
P(
x) = Prob (
x successes) are easily obtained by using
for
x > 0 and
P(0) =
F(0). The table covers all
and
p = 0.01(0.01)0.10(0.05)0.50. For values of
, probabilities may be found by interchanging the roles of âsuccessâ and âfailureâ.
Charts 1.2 (pp 27â28) give (
a) 95% and (
b) 99% confidence intervals for
p on the basis of a binomial sample of size
n in which there are
X successes. If the sample fraction
, locate its value on the bottom horizontal axis, trace up to the two curves labelled with the appropriate value of
n, and read off the confidence limits on the left-hand vertical axis; if
use the top horizontal axis and the right-hand vertical axis. For each value of n, the appropriate points have been plotted for all possible values of
X/
n and these points joined by straight lines to aid legibility. Results for values of
n not included may be obtained approximately by interpolation.
The charts may also be used âin reverseâ to provide (
a) 5% and (
b) 1% two-tailed critical regions for the hypothesis test of
against the two-sided
, or equivalently (
a)
and (
b)
one-tailed critical regions for one-sided tests. (NB âOne-sidedâ and âtwo-sidedâ relate to the nature of H
1 and to the relevant tests and statistics; âone-tailedâ and âtwo-tailedâ describe the form of critical region.)
The quantity tabulated in Table 1.3(a) (pp 29â32) is the cdf of the Poisson distribution with mean Îź:
Individual probabilities may be found as with Table 1.1. For
the cdf occupies two or more rows of the table, the first row giving
F(0) to
F(9), the second row
F(10) to
F(19), etc.
The Poisson probability chart,
Chart 1.3(b) (page 33), provides values of Prob
where
X has the Poisson distribution with mean Îź. The value of Îź, ranging from 0.1 to 100, is found on either side of the page and the probabilities are read at the bottom. There is a curve for each of the following values of
x: 1(1)25(5)100(10)150. The Îź axis has a logarithmic scale and the probability axis a normal probability scale.
Section 2: The Normal Distribution
Table 2.1(a) (pp 34â35) gives values of the standard normal cdf Ф(
z) for
z = â4.00(0.01)3.00, expressed to four decimal places (4 dp) with proportional parts for the third decimal place of
z, and also for
z = 3.00(0.01)5.00 to 6 dp. Note that the proportional parts are
subtracted if
. Further, by symmetry, i.e. using
, we may also obtain values of
to 4 dp with proportional parts for
z = 3.00(0.01)4.00 and to 6 dp for
. If
F(
x) is the cdf of the normal distribution having mean Îź and variance Ď
2, denoted
, then
.
Table 2.1(b) (page 36) gives values of
for a range of values of
z from 3.0 to 200.0.
Table 2.2 (page 36) is a brief table of ordinates
of the standard normal pdf (probability density function).
Table 2.3(a) (page 36) provides a selection of useful quantiles (percentage points) of the standard normal distribution, i.e. values of
z satisfying
. Six particularly important values are provided to 10 dp.
Table 2.3(b) (page 37) is a more comprehensive table of quantiles. Here, for
read
q on the right and bottom. For
read
q along the left and top and negate the resulting value of
z.
Table 2.4(a) (pp 38â39) gives expected values of normal order statistics (normal scores) for sample sizes
, i.e. the values
where
represents a sample of size
n from N(0,1) arranged in ascending order. The values are listed in top-down order:
where
, and remaining values may be obtained by symmetry:
. Normal scores are useful in formulating some particularly powerful nonparametric tests (see page 12); the variances of such test statistics usually involve
, and these sums of squares are given in
Table 2.4(b) (pp 38â39).
Tables 2.5(a) and (
b) (page 40) respectively give moments and quantiles of the distribution of the range
R (maximum value â minimum value) of samples from normal distributions for sample sizes up to 20. Denoting the expected (mean) range by E[
R] and central moments
of
R by
rk, the five columns of Table 2.5(a) respectively give
,
, and
where Ď
2 is the variance of the normal distribution. In particular, the first and second columns give the mean and
standard deviation of
R in units of Ď. Table 2.5(b) gives six quantiles
Rn, q on either side of the distribution of
R, again in units of Ď.
Further reading: Table 2.4: Bradley (1968, §6.2); Table 2.5: Lindgren (1976, §7.2.1).
Section 3: Continuous Probability Distributions
Table 3.1 (page 41) gives 13 quantiles
tν,q of the Student
t distribution for degrees of freedom ν covering 1(1)40,45,50(10)100,120,150, â. The quantiles are all in the right-hand half of the distributions; values in the left-hand half may be obtained by symmetry:
.
Table 3.2 (pp 42â43) gives 25 quantiles
of the chi-squared (Ď
2) distribution for degrees of freedom
ν covering 1(1)40,45,50(10)100,120, 150,200. Quantiles are provided in both the left-hand and right-hand sides of the distributions since Ď
2 distributions are not symmetric.
Table 3.3 (pp 44â47) gives six right-hand quantiles
of the Snedecor
F distribution for the ânumeratorâ degrees of freedom covering
ν1 = 1(1)10,12,15,20,30,50,â and the âdenominatorâ degrees of freedom
ν2 = 1(1)25(5)50,60(20)120, â. The six quantiles for a particular choice of (
ν1,
ν2) are provided in a block for easy reference, rather than by using a separate page for each value of
q. Critical regions for one-sided tests of
against
using the statistic
(where
s1 and
s2 are the adjusted standard deviations of the two samplesâsee page 91) require critical regions of the form
, so in this case the tables immediately give the required critical values for 100(1 â
q)% significance levels. (Interch...