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Table 1 Survival of adult females (a) and males (b) of Tenebrio molitor according to sex-ratio condition (Sex-ratio). The “simple” contrast was used for Sex-ratio (survival of males in the 50% of male condition was used as baseline). For females (a), a time-dependent procedure was used to account for the time-dependent effect of Sex-ratio on the risk of mortality (T × Sex-ratio). This procedure was not necessary for males as the effect of Sex-ratio on the risk of mortality was constant over time (b)

From: Sex-specific patterns of senescence in artificial insect populations varying in sex-ratio to manipulate reproductive effort

A. Variablesbas.e.bWaldcd.f.pdOdds ratioe
Sex-ratio  1.6120.744 
T × Sex-ratio  9.7720.008 
 75% of males vs 50% of males0.120.049.2810.0021.13
 25% of males vs 50% of males0.000.020.0510.8311.00
 75% of males vs 25% of males0.120.049.0310.0031.12
B. Variablesbs.e.Waldd.f.pOdds ratio
Sex-ratio  21.342<  0.001 
 75% of males vs 50% of males−0.380.1015.361<  0.0010.70
 25% of males vs 50% of males0.150.170.8210.3661.16
 75% of males vs 25% of males−0.530.1610.9810.0010.59
  1. ab = regression coefficient of overall survival function for variables
  2. bStandard error of regression coefficient
  3. cWald statistic for variable
  4. dSignificant level for Wald statistic. Values p ≤ 0.005 are given in bold
  5. eOdds ratio of survival for variable relative to control (=exp.(b))