r의 분산과 신뢰 구간 내에서 그리고 신뢰 구간을 계산합니다.

StackOverflow https://stackoverflow.com/questions/1401894

  •  05-07-2019
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문제

새로운 분석 화학 방법을 개발할 때 일부 데이터의 내부 및 실행 분산 사이를 계산해야합니다. 또한 r 언어를 사용 하여이 데이터의 신뢰 구간이 필요합니다.

ANOVA 또는 뭔가를 사용해야한다고 생각합니까?

내 데이터는 비슷합니다

> variance
   Run Rep Value
1    1   1  9.85
2    1   2  9.95
3    1   3 10.00
4    2   1  9.90
5    2   2  8.80
6    2   3  9.50
7    3   1 11.20
8    3   2 11.10
9    3   3  9.80
10   4   1  9.70
11   4   2 10.10
12   4   3 10.00
도움이 되었습니까?

해결책 4

나는 비슷한 문제를보고있다. Burdick and Graybill (Burdick, R. 및 Graybill, F. 1992, 분산 구성 요소에 대한 신뢰 구간, CRC Press)의 Caluclating Conferidence 간격에 대한 언급을 발견했습니다.

내가 시도한 일부 코드를 사용 하여이 값을 얻습니다.



> kiaraov = aov(Value~Run+Error(Run),data=kiar)

> summary(kiaraov)

Error: Run
    Df  Sum Sq Mean Sq
Run  3 2.57583 0.85861

Error: Within
          Df  Sum Sq Mean Sq F value Pr(>F)
Residuals  8 1.93833 0.24229               
> confint = 95

> a = (1-(confint/100))/2

> grandmean = as.vector(kiaraov$"(Intercept)"[[1]][1]) # Grand Mean (I think)

> within = summary(kiaraov)$"Error: Within"[[1]]$"Mean Sq"  # S2^2Mean Square Value for Within Run

> dfRun = summary(kiaraov)$"Error: Run"[[1]]$"Df"

> dfWithin = summary(kiaraov)$"Error: Within"[[1]]$"Df"

> Run = summary(kiaraov)$"Error: Run"[[1]]$"Mean Sq" # S1^2Mean Square for between Run

> between = (Run-within)/((dfWithin/(dfRun+1))+1) # (S1^2-S2^2)/J

> total = between+within

> between # Between Run Variance
[1] 0.2054398

> within # Within Run Variance
[1] 0.2422917

> total # Total Variance
[1] 0.4477315

> betweenCV = sqrt(between)/grandmean * 100 # Between Run CV%

> withinCV = sqrt(within)/grandmean * 100 # Within Run CV%

> totalCV = sqrt(total)/grandmean * 100 # Total CV%

> #within confidence intervals

> withinLCB = within/qf(1-a,8,Inf) # Within LCB

> withinUCB = within/qf(a,8,Inf) # Within UCB

> #Between Confidence Intervals

> n1 = dfRun

> n2 = dfWithin

> G1 = 1-(1/qf(1-a,n1,Inf)) # According to Burdick and Graybill this should be a

> G2 = 1-(1/qf(1-a,n2,Inf))

> H1 = (1/qf(a,n1,Inf))-1  # and this should be 1-a, but my results don't agree

> H2 = (1/qf(a,n2,Inf))-1

> G12 = ((qf(1-a,n1,n2)-1)^2-(G1^2*qf(1-a,n1,n2)^2)-(H2^2))/qf(1-a,n1,n2) # again, should be a, not 1-a

> H12 = ((1-qf(a,n1,n2))^2-H1^2*qf(a,n1,n2)^2-G2^2)/qf(a,n1,n2) # again, should be 1-a, not a

> Vu = H1^2*Run^2+G2^2*within^2+H12*Run*within

> Vl = G1^2*Run^2+H2^2*within^2+G12*within*Run

> betweenLCB = (Run-within-sqrt(Vl))/J # Betwen LCB

> betweenUCB = (Run-within+sqrt(Vu))/J # Between UCB

> #Total Confidence Intervals

> y = (Run+(J-1)*within)/J

> totalLCB = y-(sqrt(G1^2*Run^2+G2^2*(J-1)^2*within^2)/J) # Total LCB

> totalUCB = y+(sqrt(H1^2*Run^2+H2^2*(J-1)^2*within^2)/J) # Total UCB

> result = data.frame(Name=c("within", "between", "total"),CV=c(withinCV,betweenCV,totalCV),LCB=c(sqrt(withinLCB)/grandmean*100,sqrt(betweenLCB)/grandmean*100,sqrt(totalLCB)/grandmean*100),UCB=c(sqrt(withinUCB)/grandmean*100,sqrt(betweenUCB)/grandmean*100,sqrt(totalUCB)/grandmean*100))

> result
     Name       CV      LCB      UCB
1  within 4.926418 3.327584  9.43789
2 between 4.536327      NaN 19.73568
3   total 6.696855 4.846030 20.42647

여기서 실행 CV 사이의 신뢰 구간이 낮으므로 0보다 작으므로 NAN으로보고됩니다.

나는 이것을 할 수있는 더 좋은 방법을 갖고 싶다. 시간이되면이 작업을 수행 할 함수를 만들려고 할 수 있습니다.

폴.

--

편집 : 결국 기능을 작성했습니다.

#' avar Function
#' 
#' Calculate thewithin, between and total %CV of a dataset by ANOVA, and the
#' associated confidence intervals
#' 
#' @param dataf - The data frame to use, in long format 
#' @param afactor Character string representing the column in dataf that contains the factor
#' @param aresponse  Charactyer string representing the column in dataf that contains the response value
#' @param aconfidence What Confidence limits to use, default = 95%
#' @param digits  Significant Digits to report to, default = 3
#' @param debug Boolean, Should debug messages be displayed, default=FALSE
#' @returnType dataframe containing the Mean, Within, Between and Total %CV and LCB and UCB for each
#' @return 
#' @author Paul Hurley
#' @export
#' @examples 
#' #Using the BGBottles data from Burdick and Graybill Page 62
#' assayvar(dataf=BGBottles, afactor="Machine", aresponse="weight")
avar<-function(dataf, afactor, aresponse, aconfidence=95, digits=3, debug=FALSE){
    dataf<-subset(dataf,!is.na(with(dataf,get(aresponse))))
    nmissing<-function(x) sum(!is.na(x))
    n<-nrow(subset(dataf,is.numeric(with(dataf,get(aresponse)))))
    datadesc<-ddply(dataf, afactor, colwise(nmissing,aresponse))
    I<-nrow(datadesc)
    if(debug){print(datadesc)}
    if(min(datadesc[,2])==max(datadesc[,2])){
        balance<-TRUE
        J<-min(datadesc[,2])
        if(debug){message(paste("Dataset is balanced, J=",J,"I is ",I,sep=""))}
    } else {
        balance<-FALSE
        Jh<-I/(sum(1/datadesc[,2], na.rm = TRUE))
        J<-Jh
        m<-min(datadesc[,2])
        M<-max(datadesc[,2])
        if(debug){message(paste("Dataset is unbalanced, like me, I is ",I,sep=""))}
        if(debug){message(paste("Jh is ",Jh, ", m is ",m, ", M is ",M, sep=""))}
    }
    if(debug){message(paste("Call afactor=",afactor,", aresponse=",aresponse,sep=""))}
    formulatext<-paste(as.character(aresponse)," ~ 1 + Error(",as.character(afactor),")",sep="")
    if(debug){message(paste("formula text is ",formulatext,sep=""))}
    aovformula<-formula(formulatext)
    if(debug){message(paste("Formula is ",as.character(aovformula),sep=""))}
    assayaov<-aov(formula=aovformula,data=dataf)
    if(debug){
        print(assayaov)
        print(summary(assayaov))
    }
    a<-1-((1-(aconfidence/100))/2)
    if(debug){message(paste("confidence is ",aconfidence,", alpha is ",a,sep=""))}
    grandmean<-as.vector(assayaov$"(Intercept)"[[1]][1]) # Grand Mean (I think)
    if(debug){message(paste("n is",n,sep=""))}

    #This line commented out, seems to choke with an aov object built from an external formula
    #grandmean<-as.vector(model.tables(assayaov,type="means")[[1]]$`Grand mean`) # Grand Mean (I think)
    within<-summary(assayaov)[[2]][[1]]$"Mean Sq"  # d2e, S2^2 Mean Square Value for Within Machine = 0.1819
    dfRun<-summary(assayaov)[[1]][[1]]$"Df"  # DF for within = 3
    dfWithin<-summary(assayaov)[[2]][[1]]$"Df"  # DF for within = 8
    Run<-summary(assayaov)[[1]][[1]]$"Mean Sq" # S1^2Mean Square for Machine
    if(debug){message(paste("mean square for Run ?",Run,sep=""))}
    #Was between<-(Run-within)/((dfWithin/(dfRun+1))+1) but my comment suggests this should be just J, so I'll use J !
    between<-(Run-within)/J # d2a (S1^2-S2^2)/J
    if(debug){message(paste("S1^2 mean square machine is ",Run,", S2^2 mean square within is ",within))}
    total<-between+within
    between # Between Run Variance
    within # Within Run Variance
    total # Total Variance
    if(debug){message(paste("between is ",between,", within is ",within,", Total is ",total,sep=""))}

    betweenCV<-sqrt(between)/grandmean * 100 # Between Run CV%
    withinCV<-sqrt(within)/grandmean * 100 # Within Run CV%
    totalCV<-sqrt(total)/grandmean * 100 # Total CV%
    n1<-dfRun
    n2<-dfWithin
    if(debug){message(paste("n1 is ",n1,", n2 is ",n2,sep=""))}
    #within confidence intervals
    if(balance){
        withinLCB<-within/qf(a,n2,Inf) # Within LCB
        withinUCB<-within/qf(1-a,n2,Inf) # Within UCB
    } else {
        withinLCB<-within/qf(a,n2,Inf) # Within LCB
        withinUCB<-within/qf(1-a,n2,Inf) # Within UCB
    }
#Mean Confidence Intervals
    if(debug){message(paste(grandmean,"+/-(sqrt(",Run,"/",n,")*qt(",a,",df=",I-1,"))",sep=""))} 
    meanLCB<-grandmean+(sqrt(Run/n)*qt(1-a,df=I-1)) # wrong
    meanUCB<-grandmean-(sqrt(Run/n)*qt(1-a,df=I-1)) # wrong
    if(debug){message(paste("Grandmean is ",grandmean,", meanLCB = ",meanLCB,", meanUCB = ",meanUCB,aresponse,sep=""))}
    if(debug){print(summary(assayaov))}
#Between Confidence Intervals
    G1<-1-(1/qf(a,n1,Inf)) 
    G2<-1-(1/qf(a,n2,Inf))
    H1<-(1/qf(1-a,n1,Inf))-1  
    H2<-(1/qf(1-a,n2,Inf))-1
    G12<-((qf(a,n1,n2)-1)^2-(G1^2*qf(a,n1,n2)^2)-(H2^2))/qf(a,n1,n2) 
    H12<-((1-qf(1-a,n1,n2))^2-H1^2*qf(1-a,n1,n2)^2-G2^2)/qf(1-a,n1,n2) 
    if(debug){message(paste("G1 is ",G1,", G2 is ",G2,sep=""))
        message(paste("H1 is ",H1,", H2 is ",H2,sep=""))
        message(paste("G12 is ",G12,", H12 is ",H12,sep=""))
    }
    if(balance){
        Vu<-H1^2*Run^2+G2^2*within^2+H12*Run*within
        Vl<-G1^2*Run^2+H2^2*within^2+G12*within*Run
        betweenLCB<-(Run-within-sqrt(Vl))/J # Betwen LCB
        betweenUCB<-(Run-within+sqrt(Vu))/J # Between UCB
    } else {
        #Burdick and Graybill seem to suggest calculating anova of mean values to find n1S12u/Jh
        meandataf<-ddply(.data=dataf,.variable=afactor, .fun=function(df){mean(with(df, get(aresponse)), na.rm=TRUE)})
        meandataaov<-aov(formula(paste("V1~",afactor,sep="")), data=meandataf)
        sumsquare<-summary(meandataaov)[[1]]$`Sum Sq`
        #so maybe S12u is just that bit ?
        Runu<-(sumsquare*Jh)/n1
        if(debug){message(paste("n1S12u/Jh is ",sumsquare,", so S12u is ",Runu,sep=""))}
        Vu<-H1^2*Runu^2+G2^2*within^2+H12*Runu*within
        Vl<-G1^2*Runu^2+H2^2*within^2+G12*within*Runu
        betweenLCB<-(Runu-within-sqrt(Vl))/Jh # Betwen LCB
        betweenUCB<-(Runu-within+sqrt(Vu))/Jh # Between UCB
        if(debug){message(paste("betweenLCB is ",betweenLCB,", between UCB is ",betweenUCB,sep=""))}
    }
#Total Confidence Intervals
    if(balance){
        y<-(Run+(J-1)*within)/J
        if(debug){message(paste("y is ",y,sep=""))}
        totalLCB<-y-(sqrt(G1^2*Run^2+G2^2*(J-1)^2*within^2)/J) # Total LCB
        totalUCB<-y+(sqrt(H1^2*Run^2+H2^2*(J-1)^2*within^2)/J) # Total UCB
    } else {
        y<-(Runu+(Jh-1)*within)/Jh
        if(debug){message(paste("y is ",y,sep=""))}
        totalLCB<-y-(sqrt(G1^2*Runu^2+G2^2*(Jh-1)^2*within^2)/Jh) # Total LCB
        totalUCB<-y+(sqrt(H1^2*Runu^2+H2^2*(Jh-1)^2*within^2)/Jh) # Total UCB
    }
    if(debug){message(paste("totalLCB is ",totalLCB,", total UCB is ",totalUCB,sep=""))}
#   result<-data.frame(Name=c("within", "between", "total"),CV=c(withinCV,betweenCV,totalCV),
#           LCB=c(sqrt(withinLCB)/grandmean*100,sqrt(betweenLCB)/grandmean*100,sqrt(totalLCB)/grandmean*100),
#           UCB=c(sqrt(withinUCB)/grandmean*100,sqrt(betweenUCB)/grandmean*100,sqrt(totalUCB)/grandmean*100))
    result<-data.frame(Mean=grandmean,MeanLCB=meanLCB, MeanUCB=meanUCB, Within=withinCV,WithinLCB=sqrt(withinLCB)/grandmean*100, WithinUCB=sqrt(withinUCB)/grandmean*100,
            Between=betweenCV, BetweenLCB=sqrt(betweenLCB)/grandmean*100, BetweenUCB=sqrt(betweenUCB)/grandmean*100,
            Total=totalCV, TotalLCB=sqrt(totalLCB)/grandmean*100, TotalUCB=sqrt(totalUCB)/grandmean*100)
    if(!digits=="NA"){
        result$Mean<-signif(result$Mean,digits=digits)
        result$MeanLCB<-signif(result$MeanLCB,digits=digits)
        result$MeanUCB<-signif(result$MeanUCB,digits=digits)
        result$Within<-signif(result$Within,digits=digits)
        result$WithinLCB<-signif(result$WithinLCB,digits=digits)
        result$WithinUCB<-signif(result$WithinUCB,digits=digits)
        result$Between<-signif(result$Between,digits=digits)
        result$BetweenLCB<-signif(result$BetweenLCB,digits=digits)
        result$BetweenUCB<-signif(result$BetweenUCB,digits=digits)
        result$Total<-signif(result$Total,digits=digits)
        result$TotalLCB<-signif(result$TotalLCB,digits=digits)
        result$TotalUCB<-signif(result$TotalUCB,digits=digits)
    }
    return(result)
}

assayvar<-function(adata, aresponse, afactor, anominal, aconfidence=95, digits=3, debug=FALSE){
    result<-ddply(adata,anominal,function(df){
                resul<-avar(dataf=df,afactor=afactor,aresponse=aresponse,aconfidence=aconfidence, digits=digits, debug=debug)
                resul$n<-nrow(subset(df, !is.na(with(df, get(aresponse)))))
                return(resul)
            })
    return(result)
}

다른 팁

세 가지 관찰로 구성된 4 개의 그룹이 있습니다.

> run1 = c(9.85, 9.95, 10.00)
> run2 = c(9.90, 8.80, 9.50)
> run3 = c(11.20, 11.10, 9.80)
> run4 = c(9.70, 10.10, 10.00)
> runs = c(run1, run2, run3, run4)
> runs
 [1]  9.85  9.95 10.00  9.90  8.80  9.50 11.20 11.10  9.80  9.70 10.10 10.00

라벨 만들기 :

> n = rep(3, 4)
> group = rep(1:4, n)
> group
 [1] 1 1 1 2 2 2 3 3 3 4 4 4

실행 내에서 계산 :

> withinRunStats = function(x) c(sum = sum(x), mean = mean(x), var = var(x), n = length(x))
> tapply(runs, group, withinRunStats)
$`1`
         sum         mean          var            n 
29.800000000  9.933333333  0.005833333  3.000000000 

$`2`
  sum  mean   var     n 
28.20  9.40  0.31  3.00 

$`3`
  sum  mean   var     n 
32.10 10.70  0.61  3.00 

$`4`
        sum        mean         var           n 
29.80000000  9.93333333  0.04333333  3.00000000 

여기에서 일부 분산 분석을 할 수 있습니다.

> data = data.frame(y = runs, group = factor(group))
> data
       y group
1   9.85     1
2   9.95     1
3  10.00     1
4   9.90     2
5   8.80     2
6   9.50     2
7  11.20     3
8  11.10     3
9   9.80     3
10  9.70     4
11 10.10     4
12 10.00     4

> fit = lm(runs ~ group, data)
> fit

Call:
lm(formula = runs ~ group, data = data)

Coefficients:
(Intercept)       group2       group3       group4  
  9.933e+00   -5.333e-01    7.667e-01   -2.448e-15 

> anova(fit)
Analysis of Variance Table

Response: runs
          Df  Sum Sq Mean Sq F value  Pr(>F)  
group      3 2.57583 0.85861  3.5437 0.06769 .
Residuals  8 1.93833 0.24229                  
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 

> degreesOfFreedom = anova(fit)[, "Df"]
> names(degreesOfFreedom) = c("treatment", "error")
> degreesOfFreedom
treatment     error 
        3         8

오류 또는 그룹 내 분산 :

> anova(fit)["Residuals", "Mean Sq"]
[1] 0.2422917

치료 또는 그룹 간 분산 :

> anova(fit)["group", "Mean Sq"]
[1] 0.8586111

이것은 신뢰 구간을 할 수있는 충분한 자신감을 제공해야합니다.

함수를 적용하려는 경우 (예 : var)와 같은 요인을 가로 질러 Run 또는 Rep, 당신이 사용할 수있는 tapply:

> with(variance, tapply(Value, Run, var))
          1           2           3           4 
0.005833333 0.310000000 0.610000000 0.043333333 
> with(variance, tapply(Value, Rep, var))
          1          2          3 
0.48562500 0.88729167 0.05583333 

더 많은 시간이있을 때 이것에 균열을 일으킬 것입니다. 그러나 한편, 여기에 있습니다. dput() Kiar의 데이터 구조 :

structure(list(Run = c(1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4), Rep = c(1, 
2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3), Value = c(9.85, 9.95, 10, 9.9, 
8.8, 9.5, 11.2, 11.1, 9.8, 9.7, 10.1, 10)), .Names = c("Run", 
"Rep", "Value"), row.names = c(NA, -12L), class = "data.frame")

... 빠른 샷을 원할 경우.

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