Calculates Pearson, Spearman, polychoric, and polyserial correlation coefficients, in weighted or unweighted form. The package implements tetrachoric correlation as a special case of the polychoric and biserial correlation as a specific case of the polyserial.

A new inverse probability of selection weighted Cox model to deal with outcome-dependent sampling in survival analysis.

Analyzes and models data subject to sampling biases.
    Provides functions to estimate the density and cumulative distribution
    functions from biased samples of continuous distributions. Includes
    the estimators proposed by Bhattacharyya et al. (1988)
    <doi:10.1080/03610928808829825> and Jones (1991) <doi:10.2307/2337020>
    for density, and by Cox (2005, ISBN:052184939X) and Bose and Dutta
    (2022) <doi:10.1007/s00184-021-00824-3> for distribution, with
    different bandwidth selectors. Also includes a real length-biased
    dataset on shrub width from Muttlak (1988)
    <https://www.proquest.com/openview/3dd74592e623cdbcfa6176e85bd3d390/1?cbl=18750&diss=y&pq-origsite=gscholar>.

Search and download data from over 40 databases hosted by the World Bank, including the World Development Indicators ('WDI'), International Debt Statistics, Doing Business, Human Capital Index, and Sub-national Poverty indicators.

Provides functions to calculate the Water Deficit Index (WDI) and 
    the Evaporative Fraction (EF) using geospatial raster data such as fractional 
    vegetation cover (FVC) and surface-air temperature difference (TS-TA). 
    The package automates regression-based edge fitting and produces continuous 
    spatial maps of surface moisture and evaporative dynamics.

Provides efficient implementations of weighted dependence measures
  and related asymptotic tests for independence. Implemented measures are
  the Pearson correlation, Spearman's rho, Kendall's tau, Blomqvist's beta, and
  Hoeffding's D; see, e.g., Nelsen (2006) <doi:10.1007/0-387-28678-0> and
  Hollander et al. (2015, ISBN:9780470387375).