Python 模块中的类内相关性?

Intraclass Correlation in Python Module?

我正在寻找计算 intraclass correlation (ICC) in Python. I haven't been able to find an existing module that has this feature. Is there an alternate name, or should I do it myself? I'm aware this question was asked a year ago 由另一个用户交叉验证,但没有回复。我正在寻找比较两个评分者之间的连续分数。

您可以在 ICC or Brain_Data.icc

找到实现

ICC in R. These can be used from Python via the rpy2 包有多种实现。示例:

from rpy2.robjects import DataFrame, FloatVector, IntVector
from rpy2.robjects.packages import importr
from math import isclose

groups = [1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4,
          4, 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8]
values = [1, 2, 0, 1, 1, 3, 3, 2, 3, 8, 1, 4, 6, 4, 3,
          3, 6, 5, 5, 6, 7, 5, 6, 2, 8, 7, 7, 9, 9, 9, 9, 8]

r_icc = importr("ICC")
df = DataFrame({"groups": IntVector(groups),
                "values": FloatVector(values)})
icc_res = r_icc.ICCbare("groups", "values", data=df)
icc_val = icc_res[0] # icc_val now holds the icc value

# check whether icc value equals reference value
print(isclose(icc_val, 0.728, abs_tol=0.001))

R package psych 具有类内相关性 (ICC) 的实现,可计算多种类型的变体,包括 ICC(1,1)、ICC(1,k)、ICC(2,1)、ICC (2,k)、ICC(3,1) 和 ICC(3,k) 以及其他指标。

This page 对不同变体进行了很好的比较,

您可以通过rpy2包使用R ICC功能。

示例:

  1. 首先在 R:
  2. 中安装 psychlme4
install.packages("psych")
install.packages("lme4")
  1. 使用 rpy2:
  2. 在 Python 中计算 ICC 系数
import rpy2
from rpy2.robjects import IntVector, pandas2ri
from rpy2.robjects.packages import importr

psych = importr("psych")

values = rpy2.robjects.r.matrix(
    IntVector(
        [9,    2,   5,    8,
        6,    1,   3,    2,
        8,    4,   6,    8,
        7,    1,   2,    6,
        10,   5,   6,    9,
        6,   2,   4,    7]),
    ncol=4, byrow=True
)

icc = psych.ICC(values)

# Convert to Pandas DataFrame
icc_df = pandas2ri.rpy2py(icc[0])

结果:

                            type    ICC        F           df1   df2    p          lower bound   upper bound  
  Single_raters_absolute    ICC1    0.165783   1.794916    5.0   18.0   0.164720   -0.132910     0.722589     
  Single_random_raters      ICC2    0.289790   11.026650   5.0   15.0   0.000135   0.018791      0.761107     
  Single_fixed_raters       ICC3    0.714829   11.026650   5.0   15.0   0.000135   0.342447      0.945855     
  Average_raters_absolute   ICC1k   0.442871   1.794916    5.0   18.0   0.164720   -0.884193     0.912427     
  Average_random_raters     ICC2k   0.620080   11.026650   5.0   15.0   0.000135   0.071153      0.927240     
  Average_fixed_raters      ICC3k   0.909311   11.026650   5.0   15.0   0.000135   0.675657      0.985891  

pengouin 库以 6 种不同的方式计算 ICC,以及相关的置信度和 p 值。

您可以使用 pip install pingouinconda install -c conda-forge pingouin

安装它
import pingouin as pg
data = pg.read_dataset('icc')
icc = pg.intraclass_corr(data=data, targets='Wine', raters='Judge',
                         ratings='Scores')
data.head()

|    |   Wine | Judge   |   Scores |
|---:|-------:|:--------|---------:|
|  0 |      1 | A       |        1 |
|  1 |      2 | A       |        1 |
|  2 |      3 | A       |        3 |
|  3 |      4 | A       |        6 |
|  4 |      5 | A       |        6 |
|  5 |      6 | A       |        7 |
|  6 |      7 | A       |        8 |
|  7 |      8 | A       |        9 |
|  8 |      1 | B       |        2 |
|  9 |      2 | B       |        3 |

icc

|    | Type   | Description             |   ICC |      F |   df1 |   df2 |        pval | CI95%        |
|---:|:-------|:------------------------|------:|-------:|------:|------:|------------:|:-------------|
|  0 | ICC1   | Single raters absolute  | 0.773 | 11.199 |     5 |    12 | 0.000346492 | [0.39, 0.96] |
|  1 | ICC2   | Single random raters    | 0.783 | 27.966 |     5 |    10 | 1.42573e-05 | [0.25, 0.96] |
|  2 | ICC3   | Single fixed raters     | 0.9   | 27.966 |     5 |    10 | 1.42573e-05 | [0.65, 0.98] |
|  3 | ICC1k  | Average raters absolute | 0.911 | 11.199 |     5 |    12 | 0.000346492 | [0.65, 0.99] |
|  4 | ICC2k  | Average random raters   | 0.915 | 27.966 |     5 |    10 | 1.42573e-05 | [0.5, 0.99]  |
|  5 | ICC3k  | Average fixed raters    | 0.964 | 27.966 |     5 |    10 | 1.42573e-05 | [0.85, 0.99] |

基于Brain_Data,我修改了代码以计算相关系数ICC(2,1)、ICC(2,k)、ICC(3,1)或ICC(3,k) ) 作为 table Y 的数据输入(行中的主题和列中的重复测量)。

import os
import numpy as np
from numpy import ones, kron, mean, eye, hstack, dot, tile
from numpy.linalg import pinv

def icc(Y, icc_type='ICC(2,1)'):
    ''' Calculate intraclass correlation coefficient

    ICC Formulas are based on:
    Shrout, P. E., & Fleiss, J. L. (1979). Intraclass correlations: uses in
    assessing rater reliability. Psychological bulletin, 86(2), 420.
    icc1:  x_ij = mu + beta_j + w_ij
    icc2/3:  x_ij = mu + alpha_i + beta_j + (ab)_ij + epsilon_ij
    Code modifed from nipype algorithms.icc
    https://github.com/nipy/nipype/blob/master/nipype/algorithms/icc.py

    Args:
        Y: The data Y are entered as a 'table' ie. subjects are in rows and repeated
            measures in columns
        icc_type: type of ICC to calculate. (ICC(2,1), ICC(2,k), ICC(3,1), ICC(3,k)) 
    Returns:
        ICC: (np.array) intraclass correlation coefficient
    '''

    [n, k] = Y.shape

    # Degrees of Freedom
    dfc = k - 1
    dfe = (n - 1) * (k-1)
    dfr = n - 1

    # Sum Square Total
    mean_Y = np.mean(Y)
    SST = ((Y - mean_Y) ** 2).sum()

    # create the design matrix for the different levels
    x = np.kron(np.eye(k), np.ones((n, 1)))  # sessions
    x0 = np.tile(np.eye(n), (k, 1))  # subjects
    X = np.hstack([x, x0])

    # Sum Square Error
    predicted_Y = np.dot(np.dot(np.dot(X, np.linalg.pinv(np.dot(X.T, X))),
                                X.T), Y.flatten('F'))
    residuals = Y.flatten('F') - predicted_Y
    SSE = (residuals ** 2).sum()

    MSE = SSE / dfe

    # Sum square column effect - between colums
    SSC = ((np.mean(Y, 0) - mean_Y) ** 2).sum() * n
    MSC = SSC / dfc  # / n (without n in SPSS results)

    # Sum Square subject effect - between rows/subjects
    SSR = SST - SSC - SSE
    MSR = SSR / dfr

    if icc_type == 'icc1':
        # ICC(2,1) = (mean square subject - mean square error) /
        # (mean square subject + (k-1)*mean square error +
        # k*(mean square columns - mean square error)/n)
        # ICC = (MSR - MSRW) / (MSR + (k-1) * MSRW)
        NotImplementedError("This method isn't implemented yet.")

    elif icc_type == 'ICC(2,1)' or icc_type == 'ICC(2,k)':
        # ICC(2,1) = (mean square subject - mean square error) /
        # (mean square subject + (k-1)*mean square error +
        # k*(mean square columns - mean square error)/n)
        if icc_type == 'ICC(2,k)':
            k = 1
        ICC = (MSR - MSE) / (MSR + (k-1) * MSE + k * (MSC - MSE) / n)

    elif icc_type == 'ICC(3,1)' or icc_type == 'ICC(3,k)':
        # ICC(3,1) = (mean square subject - mean square error) /
        # (mean square subject + (k-1)*mean square error)
        if icc_type == 'ICC(3,k)':
            k = 1
        ICC = (MSR - MSE) / (MSR + (k-1) * MSE)

    return ICC