def compute_meta_data(dataf):
    """
    This function will compute the standardization computations.
    Overall, see Hedges & Olkin, 1985 for reference

    :param dataf: source data frame
    :return: dataframe with added columns per computation
    """
    return (dataf
            .assign(vi_SE2           = lambda d:  1/d['weight factor'])
            # compte unbiase z value in case of low sample soe, See Nakagawa & Cuthill, 2007
            .assign(standardized_ESU = lambda d:  d['standardized es'] * (1-(3/(4*(d['n'])-9))))
            .assign(wES              = lambda d:  d['standardized es'] * d['weight factor'])
            .assign(wES2             = lambda d:  d['weight factor']   * d['standardized es'] * d['standardized es'])
            .assign(w2               = lambda d:  d['weight factor']   * d['weight factor']))