Module stikpetP.other.thumb_point_biserial

Functions

def th_point_biserial(rp, qual='cohen')

Rule Of Thumb For Point Biserial Correlation

Simple function to use a rule-of-thumb for the Point Biserial Correlation.

Parameters

rp : float

the point-biserial correlation value

qual : {"cohen"}, optional

indication which set of rule-of-thumb to use.

Returns

pandas.DataFrame

A dataframe with the following columns:

• classification, the qualification of the effect size
• reference, a reference for the rule of thumb used

Notes

Cohen's rule of thumb for point-biserial correlation (1988, p. 82):

|r_p|	Interpretation
0.00 < 0.100	negligible
0.100 < 0.243	small
0.243 < 0.371	medium
0.371 < 1	large

See Also

r_point_biserial()

to obtain the point-biserial correlation coefficient

References

Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). L. Erlbaum Associates.

Author

Made by P. Stikker

Companion website: https://PeterStatistics.com
YouTube channel: https://www.youtube.com/stikpet
Donations: https://www.patreon.com/bePatron?u=19398076

Expand source code

def th_point_biserial(rp, qual="cohen"):
    '''
    Rule of thumb for Point Biserial Correlation
    --------------------------
    
    Simple function to use a rule-of-thumb for the Point Biserial Correlation.
    
    Parameters
    ----------
    rp : float
        the point-biserial correlation value
    qual : {"cohen"}, optional 
        indication which set of rule-of-thumb to use. 
    
    Returns
    -------
    pandas.DataFrame
        A dataframe with the following columns:
    
        * *classification*, the qualification of the effect size
        * *reference*, a reference for the rule of thumb used
    
    Notes
    -----
    Cohen's rule of thumb for point-biserial correlation (1988, p. 82):
    
    |\\|r_p\\|| Interpretation|
    |---|----------|
    |0.00 < 0.100 | negligible |
    |0.100 < 0.243 | small |
    |0.243 < 0.371 | medium |
    |0.371 < 1 | large |

    See Also
    --------
    stikpetP.correlations.cor_point_biserial.r_point_biserial : to obtain the point-biserial correlation coefficient
    
    References
    ----------
    Cohen, J. (1988). *Statistical power analysis for the behavioral sciences* (2nd ed.). L. Erlbaum Associates.

    Author
    ------
    Made by P. Stikker
    
    Companion website: https://PeterStatistics.com  
    YouTube channel: https://www.youtube.com/stikpet  
    Donations: https://www.patreon.com/bePatron?u=19398076

    '''
    
    if (qual=="cohen"):
        ref = "Cohen (1988, p. 82)"
    
        if (abs(rp)<0.1):
            qual = "negligible"
        elif (abs(rp)<0.243):
            qual = "small"
        elif (abs(rp)<0.371):
            qual = "medium"
        else:
            qual = "large"

    results = pd.DataFrame([[qual, ref]], columns=["classification", "reference"])
    
    return(results)