Table 2.

Summary of results for extrapolations from the minimum dataset for the moderate-$J_{\text{c}}$ WST-ITER conductor, showing reductions in RMSE and RMSFD values for the ESE equation-set (2) similar to those in table 1 (red-italic values). These results are for voltage tap 1 on the WST-ITER conductor, located at the center of the magnet. Essentially the same results were obtained for taps 2 and 3 located just above and below the magnet center (not shown), which contribute statistical significance to the results. Differences in parameters between corresponding cases are highlighted in red (‘var’ denotes ‘variable’).

Case #	WST Dataset (moderate-$J_{\text{c}}$ ITER conductor): Extrapolation test cases		RMSFD (%)	RMSE (%)
Test case with all free parameters
1	All parameters simultaneously fitted		116.0	2.194
Polynomial ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon })$, Taylor (2005)
2	Durham:	polynomial ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =2,\eta =\mathrm{var},w=2.2,s=1,v=1.5,p=0.5665,q=1.8111$	13.6	0.340
3	ESE:	polynomial ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =2,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$	5.0	0.168
Deviatoric ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon })$, ten Haken (1994), Godeke et al (2006), Arbelaez et al (2009), Mentink (2008,2014)
4	G/ITER:	deviatoric ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =1,\eta =2,w=3.0,s=1,v=1.52,p=0.5665,q=1.8111$	8.8	0.268
5	ESE:	deviatoric ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =1,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$	5.5	0.144
6	MAG:	deviatoric ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\eta -\mu =1,\mu =\mathrm{var},w=3.0,s=1,v=1.52,p=0.5665,q=1.8111$	8.8	0.268
7	ESE:	deviatoric ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\eta -\mu =1,\mu =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$	5.5	0.145
Extended power law ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon })$, NIST (Ekin 2006)
8	ESE:	extended power law ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =0,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$	6.3	0.150
9	ESE:	extended power law ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon })\mu =1,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$	5.4	0.139
10	ESE:	extended power law ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =2,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$	5.4	0.172
Invariant strain function ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon })$, Markiewicz (2006)
11	ESE:	invariant strain ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =1,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5,q=2.0613$	5.3	0.135
Exponential ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon })$, CERN (Bordini et al 2013)
12	ESE:	exponential ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =0,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$	6.7	0.148
13	ESE:	exponential ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =1,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$	5.7	0.134
14	ESE:	exponential ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =1,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$, $\text{fit only}{\mathbf{\text{ε}}}_0\ge -0.57\text{\%}$	6.4	0.181
15	ESE:	exponential ${\mathit{b}}_{\mathbf{\text{c}}\mathbf{2}}(\mathit{\epsilon }),\mu =2,\eta =\mathrm{var},w=3.0,s=\mathrm{var},v=1.5,p=0.5665,q=1.8111$	5.4	0.163