close prices from 2001 to 2020, (ii) 3744 close prices
from 2006 to 2020, (iii) 2895 close prices from 2011
to 2020, (iv) 1247 close prices from 2016 to 2020,
and (v) 251 close prices for 2020.
2.2 Random Walk
The random walk (Feller, 1968) is practically
straightforward and easily understandable because it
simply records a movement in x, y coordinates. This
movement starting from the origin is dictated to move
just one unit along both axes. Because the x-axis
represents the time course, so the movement along the
x-axis is always towards the positive direction. In
contrast, the movement along y-axis can go two
ways, i.e. each movement can either be positive, 1, or
negative, –1. Historically, 1/–1 came from tossing a
fair coin, but it now can achieve through a random
number generator in any computer program because
the outcome of tossing a coin is a pseudo-random
event with the Monte Carlo algorithm such as
SigmaPlot (SPSS Inc, 2002).
2.3 Crude Oil Close Price in
Conformation of a Random Walk
To be simulated by random walk, it is better to
convert the crude oil close price into the
conformation of a random walk. This is relatively
easily done by comparing a crude oil close price with
that in its preceding trading day, and by then
assigning 1 or –1 if the comparison results in larger
or smaller.
In the x, y coordinates, both random walk
simulation and crude oil close price in conformation
of a random walk are spotted as the trading date goes
along the x-axis and 1 or –1 moves along the y-axis.
The, we can compare the difference between these
two profiles to determine the good-of-fitness.
Because each seed in the command to generate the
random numbers generates different series of random
numbers, which results in different random walk
simulations, so we find the seed for good-of-fitness
from 100 000 seeds.
2.4 Random Walk in Decimal
Conformation
The conversion of crude oil close price into the 1/–1
conformation would be accused of oversimplifying
the real-life complicated situation although it answers
the simplest question of whether the crude oil goes up
or down overnight. To overcome this shortage, we
should push the classical random walk to the decimal
conformation from the 1/–1 conformation. This is not
difficult to do because we can simply omit the step of
comparison of sequential random numbers and
assignment of the 1 or 1, but directly use these
generated random numbers to form a random walk
simulation. In such a case, we need to set the
command with relevant upper and lower ranges.
2.5 Worked Example
Table I shows a worked example on the procedure to
create random walk simulations. Columns 1 and 2 are
the data documented in NY Mercantile. Column 3 is
the comparison between two sequential crude oil
close prices, for example, the crude oil close price is
$ 61.18 on January 2, 2020 (Columns 1 and 2) while
the price on January 3, is $ 63.05 (Columns 1 and 2),
which is higher than its preceding day, so we assign
1 to the second cell in Column 3, and continue this
comparison until the end of Table I. Column 4 is the
created random walk for the crude oil close price in
the 1/–1 conformation, which is the accumulation of
data in Column 3. Column 5 is the random numbers,
which were generated by SigmaPlot using a seed of
4.33068. Column 6 is the comparison between two
sequential random numbers in Column 5. Column 7
is a random walk, which is in fact a simulation on this
particular seed of 4.33068. Column 8 is the random
numbers, which were generated by SigmaPlot using
a seed of 6.16373 with upper and lower ranges of
standard deviations of crude oil close price for 2020.
Column 9, although it is similar to the operation for
Column 7, is the addition of cells in Column 1 with
the next cells in Column 8, which is a random walk
simulation in the decimal conformation.
Table 1: Procedure to create random walk simulations.
Date Crude
Oil Close
Price
Compare
Preceding
Close Price
Random Walk in
1 or–1
Conformation
Generated
Random Number
Compare
Preceding
Random Number
Random Walk in
1 or–1
Conformation
Generated
Random
Number
Random Walk
in Decimal
Conformation
January 2, 2020 61.18 0 0.892394 0 –1.293315
January 3, 2020 63.05 1 1 –0.40909 –1 –1 1.915306 63.1
January 6, 2020 63.27 1 2 –0.641479 –1 –2 4.652787 67.75
January 7, 2020 62.7 –1 1 0.860897 1 –1 –2.84741 64.9
January 8, 2020 59.61 –1 0 0.645762 –1 –2 0.478926 65.38
January 9, 2020 59.56 –1 –1 –0.339257 –1 –3 –4.264635 61.11