Item response theory (IRT) observed score kernel equating was evaluated and compared with equipercentile equating, IRT observed score equating, and kernel equating methods by varying the sample size and test length. Considering that IRT data simulation might unequally favor IRT equating methods, pseudo tests and pseudo groups were also constructed to make equating results comparable with those from the IRT data simulation. Identity equating and the large sample single group rule were both set as criterion equating (or true equating) on which local and global indices were based. Results show that in random equivalent groups design, IRT observed score kernel equating is more accurate and stable than others. In non-equivalent groups with anchor test design, IRT observed score equating shows lowest systematic and random errors among equating methods. Those errors decrease as a shorter test and a larger sample are used in equating; nevertheless, effect of the latter one is ignorable. No clear preference for data simulation method is found, though still affecting equating results. Preferences for true equating are spotted in random Equivalent Groups design. Finally, recommendations and further improvements are discussed.

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Discoveries of juvenile primary bone malignant neoplasm have been rare in archaeological settings. This study presents the first case as such from ancient China. An individual (M799) aged 14–17 years from the Dongxin cemetery of the Northern Wei Dynasty (386–534 CE), Datong, Shanxi Province, was found with signs of the bone malignant neoplasm. The skeleton of the juvenile was macroscopically examined with the aid of computed tomography imaging. Results demonstrated that a bony outgrowth was found on the distal one third of the diaphysis of the left femur; both osteoblastic and osteolytic processes were present on the lesion (about 148 mm long), and the highly dense and lobulated exophytic mass protruded about 50 mm from the posterior aspect of the diaphysis. A periosteal new bone reaction was found on the adjacent cortex while the medullary cavity was invaded by the lesion. Osteosarcoma was considered the most likely diagnosis, with differential diagnoses of Ewing sarcoma and chondrosarcoma. Otherwise, the disease had no asymmetric effect on femoral length. This rare case enriches our knowledge on the paleoepidemiological patterns of osteosarcoma and other malignant neoplasms from the past.

China's Xinjiang Uyghur Autonomous Region has long been a vital link between Europe and Eastern Asia. Xinjiang's geographical location and natural environment have led to unique dietary habits and traditions among both the region's modern inhabitants and their ancient forebears. Here, we report on the analysis of human dental residue samples unearthed from the Jiayi Cemetery, a 10 th to 2 nd century BCE mortuary complex located in the Turpan Basin, Xinjiang, generating ancient starch granules produced by vegetal foodstuffs. Morphological analysis of starch granules and comparative data indicate that crops of Triticeae tribe and subfamily Panicoideae comprised a large portion of the diet, whereas common legumes, nuts, root, and tuber were also present, although in relatively smaller proportions. The discovery of these plant starch granules in archaeological context provides direct evidence of the Jiayi population's vegetal diet and sheds light on agricultural practices during this period. With supporting evidence drawn from zooarchaeological, archaeobotanical, and paleo-isotopic studies of Bronze Age sites in Xinjiang, we conclude that the people interred in the Jiayi Cemetery practiced cereal crop cultivation and animal husbandry in the Late Bronze and Early Iron Ages. The species of cereal crops represented suggest meaningful economic communication between Central and