In the academic landscape, scientific research has been primarily conducted through research institutions, which requires a massive influx of funds from various sources. Presently, these funding bodies have been moving from trust-based funding to performance-based evaluation systems for granting funds to the research bodies. This has led to the rise in popularity of various indices or statistics that measure institutional research strength or expertise. Institutional research expertise usually focuses on publication volume and its impact measured using the widely used h- and g-indices. However, these indices fail to capture the thematic expertise of research for institutions. To address this gap, two new expertise indicators, namely the x-index, the x_d-index, and bias-adjusted variants, the field-normalised x_d-index, and the fractional x_d-index, were introduced recently. Additionally, we propose two new variants, the category-adjusted x-index and the inverse variance weighted x_d-index, which further account for resolvable bias, and a novel statistic, the x_o-index, which acts as a measure of the overall research expertise. While several packages that calculate the traditional h- and g-indices exist, these novel expertise indices are yet to be included in such existing packages. The 'xxdi' R package provides simple functions that implement these expertise indices and their variants, enabling their utilisation by the wider research community. A stable version of the package is available on CRAN (https://doi.org/10.32614/CRAN.package.xxdi) and an in-development version on GitHub (https://github.com/nilabhrardas/xxdi).

翻译：在学术领域，科学研究主要通过研究机构进行，这需要从多种渠道获得大量资金投入。目前，资助机构正从基于信任的资助模式转向基于绩效的评估体系，以决定向研究机构提供资金。这一转变推动了各种衡量机构研究实力或专业度的指数或统计指标的兴起。机构研究专业度通常关注论文产出量及其影响力，并以广泛使用的h指数和g指数进行衡量。然而，这些指数未能捕捉机构在研究主题层面的专业度。为弥补这一不足，近期引入了两种新的专业度指标，即x指数和x_d指数，以及其偏差调整变体（领域标准化x_d指数和分数化x_d指数）。此外，我们提出了两种新变体——类别调整x指数和逆方差加权x_d指数，以进一步解决可校正偏差；同时提出了一种新统计量x_o指数，用于衡量整体研究专业度。尽管已有多个计算传统h指数和g指数的软件包，但这些新型专业度指数尚未被纳入现有软件包。'xxdi' R语言包提供了实现这些专业度指数及其变体的简易函数，便于更广泛的研究社区使用。该包的稳定版已在CRAN发布（https://doi.org/10.32614/CRAN.package.xxdi），开发版可在GitHub获取（https://github.com/nilabhrardas/xxdi）。