我使用模型进行一些预测时会有问题,r显示此消息Warning message prediction from a rank-deficient fit may be misleading
,我该如何解决?我认为我的模型是正确的,这是失败的预测,我不知道为什么。
在这里,您可以逐步看到我在做什么以及模型的摘要:
myModel <- lm(margin~.,data = dataClean[train,c(target,numeric,categoric)])
Call:
lm(formula = margin ~ ., data = dataClean[train, c(target, numeric, categoric)])
Residuals:
Min 1Q Median 3Q Max
-0.220407 -0.035272 -0.003415 0.028227 0.276727
Coefficients: (2 not defined because of singularities)
Estimate Std. Error t value Pr(>|t|)
(Intercept) 6.061e-01 2.260e-02 26.817 < 2e-16 ***
price 1.042e-05 8.970e-06 1.162 0.245610
shipping 1.355e-03 2.741e-04 4.943 9.25e-07 ***
categoryofficeSupplies -7.721e-02 2.295e-02 -3.364 0.000802 ***
categorytechnology -3.993e-02 2.325e-02 -1.717 0.086249 .
subCategorybindersAndAccessories -1.650e-01 1.421e-02 -11.612 < 2e-16 ***
subCategorybookcases 3.337e-04 2.328e-02 0.014 0.988565
subCategorychairsChairmats -3.104e-02 2.106e-02 -1.474 0.140831
subCategorycomputerPeripherals 1.356e-02 1.293e-02 1.049 0.294604
subCategorycopiersAndFax -1.943e-01 2.944e-02 -6.598 7.27e-11 ***
subCategoryenvelopes -1.648e-01 2.045e-02 -8.057 2.62e-15 ***
subCategorylabels -1.534e-01 1.984e-02 -7.730 3.00e-14 ***
subCategoryofficeFurnishings -8.827e-02 2.220e-02 -3.976 7.61e-05 ***
subCategoryofficeMachines -1.521e-01 1.639e-02 -9.281 < 2e-16 ***
subCategorypaper -1.624e-01 1.363e-02 -11.909 < 2e-16 ***
subCategorypensArtSupplies -8.484e-04 1.524e-02 -0.056 0.955623
subCategoryrubberBands 3.174e-02 2.245e-02 1.414 0.157854
subCategoryscissorsRulersTrimmers 1.092e-01 2.327e-02 4.693 3.13e-06 ***
subCategorystorageOrganization 1.219e-01 1.575e-02 7.739 2.82e-14 ***
subCategorytables NA NA NA NA
subCategorytelephoneAndComunication NA NA NA NA
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 0.08045 on 858 degrees of freedom
Multiple R-squared: 0.6512, Adjusted R-squared: 0.6439
F-statistic: 88.98 on 18 and 858 DF, p-value: < 2.2e-16
estimateModel <- predict(myModel, type="response", newdata=dataClean[test, c(numeric,categoric,target)])
Warning message:
In predict.lm(myModel, type = "response", newdata = dataClean[test, :
prediction from a rank-deficient fit may be misleading
您的两个子类别级别的相关系数被抑制了。这意味着每个人都可以通过价格和运输的某种组合以及其他类别和子类别级别进行100%的预测。在R文档中,这被称为"混蛋"。警告可能很重要,尽管与@zheyuanli同意可能是良性的。我认为此特定的警告可能是由于缺失值引起的,因为当任何一个变量具有丢失值时,R回归功能通常以某种方式删除整个行。两个变量之间存在100%相关性的理论也不太可能。如果您想查找可能引起的组合,我建议从
开始with( dataClean , table( category, SubCategory) )
我预测您将在一个子类别上找到一个或多个类别行。