Should age-period-cohort analysts accept innovation without scrutiny? A response to Reither, Masters, Yang, Powers, Zheng and Land

Clarifying hierarchical age–period–cohort models: A rejoinder to Bell and Jones

“…We concluded that “when more reasonable assumptions are employed – that is, when associational nonlinearities are permitted in a data structure that is truly three-dimensional – the HAPC-CCREM approach consistently performs well” (Reither et al, 2015, 9). Ostensibly to test our claim, B&J (2015) invent a data structure that borrows the period trend from our second equation and the age trend from our fourth equation. They also create a cohort trend that, curiously, is based on the pattern of period effects shown in Figure 4 of (Reither et al, 2015).…”

“…In their commentary, B&J (2015) assert that discrepancies across model selection statistics means that they have a tendency to “find the incorrect answer” (332). Although it is true that model selection statistics such as AIC and BIC will occasionally disagree and/or point to the incorrect model, this is not particularly surprising or unique to APC research.…”

“…To contest this finding, Bell and Jones (2015) invent a data generating process (DGP) that borrows age, period and cohort effects from different equations in Reither et al (2015). When HAPC models applied to data simulated from this DGP fail to recover the patterning of APC effects, B&J reiterate their view that these models provide “misleading evidence dressed up as science.” Despite such strong words, B&J show no curiosity about their own simulated data—and therefore once again misapply HAPC models to data that violate important assumptions.…”

Cohort Changes in the Social Distribution of Tolerant Sexual Attitudes

“…Cohort differences in the SES distribution of sexual tolerance would reveal whether tolerance has diffused from high to low SES groups as it has in the United States. Fourth, estimating age, period, and cohort effects with cross-classified mixed models (Yang and Land, 2006) has generated controversy (Bell and Jones, 2013, 2014, 2015; Reither et al 2015). The cohort interactions presented here appear to be robust and show in models that exclude age and use measures related to family, work, and religion to capture life course effects directly.…”

“… 4 Much debate exists over the ability to separate age, period, and cohort effects using the Yang and Land hierarchical model (Bell and Jones, 2013, 2014, 2015; Reither et al, 2015). Although I report the mixed models estimates, the findings do not appear dependent on the estimation technique.…”