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Markov chain theory plays an important role in statistical inference both in the formulation
of models for data and in the construction of efficient algorithms for inference. The use of Markov chains
in modeling data has a long history, however the use of Markov chain theory in developing algorithms for
statistical inference has only become popular recently. Using mark-recapture models as an illustration,
we show how Markov chains can be used for developing demographic models and also in developing
efficient algorithms for inference. We anticipate that a major area of future research involving mark-recapture
data will be the development of hierarchical models that lead to better demographic models that account
for all uncertainties in the analysis. A key issue is determining when the chains produced by Markov
chain Monte Carlo sampling have converged.

The current military assignment policy of United States prohibits the assignment of females to billets with high risk of combat exposure. As part of an Army review of this policy, the authors analyzed deployment and promotion risk for combat medics. The effect of current policy on male deployment and female promotion risk was unknown. In light of other countries' policies and current operational considerations, senior military leaders sought to understand the effects of existing policy on a low-density, high-value occupational specialty, the combat medic. The authors found evidence that male medics deployed 2.07 times more frequently than female medics. The authors also found evidence that senior male medics (staff sergeants) deployed even more frequently (3.65-1) than their female counterparts. Perhaps as a result, the male combat medics experience higher likelihood of promotion from staff sergeant (E-6) to the rank of sergeant first class (E-7); however, the magnitude of that benefit was about one-third of the deployment risk. The results confirm the existence of gender-based deployment risk and promotion disparity. Based upon this analysis, the authors recommended the deprecation of current gender coding for combat medics to the senior levels of the US Army. [Reprinted by permission; copyright Inter-University Seminar on Armed Forces and Society/Sage Publications Inc.]

The current military assignment policy of United States prohibits the assignment of females to billets with high risk of combat exposure. As part of an Army review of this policy, the authors analyzed deployment and promotion risk for combat medics. The effect of current policy on male deployment and female promotion risk was unknown. In light of other countries' policies and current operational considerations, senior military leaders sought to understand the effects of existing policy on a low-density, high-value occupational specialty, the combat medic. The authors found evidence that male medics deployed 2.07 times more frequently than female medics. The authors also found evidence that senior male medics (staff sergeants) deployed even more frequently (3.65–1) than their female counterparts. Perhaps as a result, the male combat medics experience higher likelihood of promotion from staff sergeant (E-6) to the rank of sergeant first class (E-7); however, the magnitude of that benefit was about one-third of the deployment risk. The results confirm the existence of gender-based deployment risk and promotion disparity. Based upon this analysis, the authors recommended the deprecation of current gender coding for combat medics to the senior levels of the US Army.

AbstractInfants' avoidance of drop‐offs has been described as an affordance learning that is not transferable between different locomotor postures. In addition, there is evidence that infants perceive and act similarly around real and water cliffs. This cross‐sectional study investigated the effects of specific locomotor experiences on infants' avoidance behaviour using the Real Cliff/Water Cliff paradigm. The experiments included 102 infants, 58 crawling, but pre‐walking, infants (Mage = 11.57 months, SD = 1.65) with crawling experience ranging between 0.03 and 7.4 months (M = 2.16, SD = 1.71) and 44 walking infants (Mage = 14.82 months, SD = 1.99), with walking experience ranging between 0.13 and 5.2 months (M = 1.86, SD = 1.28). The association between crawling experience and crawlers' avoidance of the real and water cliffs was confirmed. Importantly, crawling and total self‐produced locomotor experience, and not walking experience, were associated with walkers' avoidance behaviour on both cliffs. These results suggest that some degree of perceptual learning acquired through crawling experience was developmentally transferred to the walking posture. A longer duration of crawling experience facilitates a more rapid recalibration to the new walking capability. In addition, there was no difference in infants' avoidance of falling on the real and the water cliff. However, infants explored the water cliff more than the real cliff, revealing more enticement to examine bodies of water than for drop‐offs. A video abstract of this article can be viewed at https://youtu.be/23LXIGiLhHI