. Author manuscript; available in PMC: 2024 Sep 1.

Published in final edited form as: J Res Crime Delinq. 2022 Oct 11;61(2):224–267. doi: 10.1177/00224278221129886

Table 3.

Estimated Inter-cohort Average Deviations^a of Alleged Homicide Offending and Victimization by Race.

	(A) Alleged Offending								(B) Victimization

	Black				White				Black				White

Cohort	Coef.	IRR	S.E.	Sig.	Coef.	IRR	S.E.	Sig.	Coef.	IRR	S.E.	Sig.	Coef.	IRR	S.E.	Sig.
1930	0.386	1.471	0.046	^***	0.075	1.078	0.044		0.362	1.436	0.038	^***	0.135	1.145	0.034	^***
1935	0.318	1.374	0.032	^***	0.114	1.120	0.030	^***	0.316	1.372	0.027	^***	0.122	1.130	0.024	^***
1940	0.251	1.286	0.026	^***	0.081	1.085	0.023	^***	0.172	1.187	0.022	^***	0.094	1.099	0.019	^***
1945	0.130	1.139	0.022	^***	0.029	1.029	0.019		0.059	1.061	0.018	^***	−0.002	0.998	0.016
1950	−0.015	0.986	0.019		−0.064	0.938	0.016	^***	0.005	1.005	0.015		−0.055	0.947	0.014	^***
1955	−0.160	0.852	0.017	^***	−0.098	0.907	0.015	^***	−0.118	0.889	0.013	^***	−0.061	0.941	0.012	^***
1960	−0.269	0.764	0.016	^***	−0.101	0.904	0.013	^***	−0.205	0.814	0.013	^***	−0.061	0.941	0.011	^***
1965	−0.212	0.809	0.016	^***	−0.065	0.937	0.014	^***	−0.185	0.831	0.013	^***	−0.056	0.946	0.012	^***
1970	−0.056	0.945	0.015	^***	0.007	1.007	0.013		−0.031	0.970	0.012	^*	−0.044	0.957	0.012	^***
1975	0.140	1.151	0.015	^***	0.148	1.159	0.014	^***	0.104	1.109	0.013	^***	0.079	1.082	0.014	^***
1980	0.187	1.206	0.015	^***	0.184	1.203	0.014	^***	0.137	1.146	0.013	^***	0.122	1.130	0.014	^***
1985	0.117	1.124	0.015	^***	0.071	1.073	0.015	^***	0.083	1.086	0.014	^***	0.061	1.063	0.016	^***
1990	0.135	1.144	0.015	^***	−0.035	0.966	0.018	^*	0.101	1.107	0.015	^***	0.021	1.021	0.018
1995	0.032	1.032	0.019		−0.228	0.796	0.023	^***	0.060	1.062	0.019	^**	−0.091	0.913	0.025	^***
2000	0.031	1.031	0.029		−0.260	0.771	0.034	^***	0.102	1.108	0.030	^***	−0.126	0.881	0.038	^***

Notes:

p<.05

^**

p<.01

^***

p<.001. IRR=Incident Rate Ratio; S.E.=Standard Error.

An Inter-cohort average deviation represents a cohort’s average deviation from the predicted rate determined by age and period main effects. A positive inter-cohort deviation represents higher-than-expected risks, whereas a negative inter-cohort deviation represents lower-than-expected risks. A small inter-cohort deviation that is not significantly different from zero suggests that on average, a cohort does not deviate from the expected rate determined by age and period main effects.