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Fix $c \in [K]$. The difference of the corresponding terms the hypotheses means can be written as

E1[εc]E0[εc]=D1(c)+D2(c)=(m1)(nm1)ν(c)(1)(μ(c)(1)ν(c)(1))+(m2)([μ(c)(1)]2[ν(c)(1)]2)E_1[\varepsilon_c] - E_0[\varepsilon_c] = D_1^{(c)} + D_2^{(c)} = \binom{m}{1} \binom{n-m}{1} \nu_{(c)}^{(1)} (\mu_{(c)}^{(1)} - \nu_{(c)}^{(1)}) + \binom{m}{2} \left( [\mu_{(c)}^{(1)}]^2 - [\nu_{(c)}^{(1)}]^2 \right)

(here $D_i^{(c)}$ corresponds to the edge-count that includes edges with exactly $i$ anomalous vertices). The reader can verify that $\frac{Var_1(T^*)}{Var_0(T^*)} \to 1$. Moreover, given that the limiting distribution (under the null) is normal, we write

cα=zαVar0(T)+E0[T2W]c_{\alpha} = z_{\alpha} \sqrt{Var_0(T^*)} + E_0[T_2^W]

and thus

β2W=P{Z>zαlimn(E1[T2W]E0[T2W]Var0(T))}.\beta_2^W = \mathbb{P} \left\{ Z > z_\alpha - \lim_{n \to \infty} \left( \frac{E_1[T_2^W] - E_0[T_2^W]}{\sqrt{Var_0(T^*)}} \right) \right\}.

Recall that $Var_0(T^*) = \Theta(n^3)$; thus, if

cwcD1(c)0\sum_c w_c D_1^{(c)} \neq 0

(i.e. there is signal in the null-to-anomaly connectivity) then the limiting power $\beta_2^W > \alpha$ when $\frac{m(n-m)}{\sqrt{n^3}} \to 0$ or, equivalently, when $m = \Omega(\sqrt{n})$ (similarly, if $m = \omega(\sqrt{n})$ then $\beta_2^W \to 1$). Furthermore, if

cwcD1(c)=0\sum_c w_c D_1^{(c)} = 0

(i.e. there is no signal in the null-to-anomaly connectivity) the limiting power $\beta_2^W > \alpha$ when $\sum_c w_c D_2^{(c)} \neq 0$ and $\frac{m^2}{\sqrt{n^3}} \to 0$ (which is equivalent to $m = \Omega(\sqrt[4]{n^3})$). Moreover, if $m = \omega(\sqrt[4]{n^3})$ under these conditions then $\beta_2^W \to 1$.

It follows that the optimal choice of weights ($w_1, \dots, w_K$) is the one which maximizes the expression

limn(E1[T2W]E0[T2W]Var0(T))\lim_{n \to \infty} \left( \frac{E_1[T_2^W] - E_0[T_2^W]}{\sqrt{Var_0(T^*)}} \right)

in either of the two above-mentioned cases.

3.2 The Attributed Number of Triangles Fusion

We begin by writing

τ=c[K]τc+bcτb,c+db,cτb,c,d.\tau = \sum_{c \in [K]} \tau_c + \sum_{b \neq c} \tau_{b,c} + \sum_{d \neq b,c} \tau_{b,c,d}.

We denote the number-of-triangles fusion invariant to be

T3W=c[K]wcτc+bcwb,cτb,c+db,cwb,c,dτb,c,d.T_3^W = \sum_{c \in [K]} w_c \tau_c + \sum_{b \neq c} w_{b,c} \tau_{b,c} + \sum_{d \neq b,c} w_{b,c,d} \tau_{b,c,d}.

Similar to what was done in the previous section, we obtain

E0[T]=(n3)[c[K]wc[ν(c)(2)]3+bcwb,c3ν(b)(2)[ν(b,c)(1,1)]2+db,cwb,c,d3ν(b,c)(1,1)ν(b,d)(1,1)ν(c,d)(1,1)]E_0[T^*] = \binom{n}{3} \left[ \sum_{c \in [K]} w_c [\nu_{(c)}^{(2)}]^3 + \sum_{b \neq c} w_{b,c} 3\nu_{(b)}^{(2)} [\nu_{(b,c)}^{(1,1)}]^2 + \sum_{d \neq b,c} w_{b,c,d} 3\nu_{(b,c)}^{(1,1)} \nu_{(b,d)}^{(1,1)} \nu_{(c,d)}^{(1,1)} \right]