Table 1

 Effect of concurvity on confidence interval coverage*. Results of the simulation study using asymptotic (standard method in gam software) and conditional bootstrap. True coefficient = 0.001

ConcurvityCoverage*
AsymptoticBootstrap
*Percentage of replicates that include the true value of the coefficient within the 95% CI of the true coefficient 0.001. Nominal coverage is 0.95. †Degree of concurvity for our real data.
0.0450.9620.964
0.1030.9460.946
0.1490.9500.946
0.1990.9210.938
0.2510.9210.951
0.286 0.905 0.952
0.3290.9070.961
0.3990.8790.955
0.4510.8630.940
0.4980.8610.946
0.5330.8620.940
0.6320.8010.950