1. Introduction. This paper discusses a special form of positive dependence.
Positive dependence may refer to two random variables that have
a positive covariance, but other definitions of positive dependence have
been proposed as well; see [24] for an overview. Random variables X =
(X1, . . . , Xd) are said to be associated if cov{f(X), g(X)} ≥ 0 for any
two non-decreasing functions f and g for which E|f(X)|, E|g(X)|, and
E|f(X)g(X)| all exist [13]. This notion has important applications in probability
theory and statistical physics; see, for example, [28, 29].
However, association may be difficult to verify in a specific context. The
celebrated FKG theorem, formulated by Fortuin, Kasteleyn, and Ginibre in
[14], introduces an alternative notion and establishes that X are associated if
∗
SF was supported in part by an NSERC Discovery Research Grant, KS by grant
#FA9550-12-1-0392 from the U.S. Air Force Office of Scientific Research (AFOSR) and
the Defense Advanced Research Projects Agency (DARPA), CU by the Austrian Science
Fund (FWF) Y 903-N35, and PZ by the European Union Seventh Framework Programme
PIOF-GA-2011-300975.
MSC 2010 subject classifications: Primary 60E15, 62H99; secondary 15B48
Keywords and phrases: Association, concentration graph, conditional Gaussian distribution,
faithfulness, graphical models, log-linear interactions, Markov property, positive
Step-by-step explanation:
cos 45° = distance to east / total distance=7,2
distance to east = cos 45° * 7,2 = 5,1 km
Answer: a=36; b=18
Step-by-step explanation:
1. You know that the sum of two numbers is 54, then, you have:
a+b=54
2. According to the problem, the larger number is 18 more than the sampler number, this can be expressed as following:
a=b+18
3. Then, you must substitute the second equation into the first equation and solve for b:
b+18+b=54
b=18
4. Then the value of a is:
a+18=55
a=36
A=adult ticket s=student ticket
64a+132s=$1040
a=2s
128a+132s=$1040
260tickets=$1040
$1040/260=$4
s=$4 (1s=$4x1)
a=$8 (2s=$4x2)
132s=$528 (132x$4)
64a=$512 (64x$8)
TOTAL=$1040
