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edited Dec 21, 2016 at 2:09

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I have been using NonLinearModelFitNonlinearModelFit in a current study. Outputs from this procedure include AIC and AICc.

AICc can be calulatedcalculated from AIC via the following relation:

AICc = AIC + ( 2k(k+1))/ (n-k-1)$$\text{AICc} = \text{AIC} + \frac{2k(k+1)}{n-k-1}$$

If a model with 3$3$ parameters is considered k = 3, then $k = 3$, and if 5 data$5$ data points are used in the fitting then n =5$n = 5$. With these assumptions,

( 2k(k+1))/ (n-k-1)= (2*3(3+1))/ (5-3-1) = 24/1 =24. The$$\frac{2k(k+1)}{n-k-1}=\frac{2\times 3(3+1)}{5-3-1}=24/1=24$$

The denominator of this expression would be zero for 4$4$ data points.

I have performed an analysis with 5 data points. The value of AICc should be AIC +24+ 24. In this instance NonLinearModelFitNonlinearModelFit calculated AICc = InfinityInfinity.

Is this an Errorerror or am I missing somthingsomething?

I have been using NonLinearModelFit in a current study. Outputs from this procedure include AIC and AICc.

AICc can be calulated from AIC via the following relation

AICc = AIC + ( 2k(k+1))/ (n-k-1)

If a model with 3 parameters is considered k = 3 and if 5 data points are used in the fitting then n =5. With these assumptions

( 2k(k+1))/ (n-k-1)= (2*3(3+1))/ (5-3-1) = 24/1 =24. The denominator of this expression would be zero for 4 data points.

I have performed an analysis with 5 data points. The value of AICc should be AIC +24. In this instance NonLinearModelFit calculated AICc = Infinity.

Is this an Error or am I missing somthing?

I have been using NonlinearModelFit in a current study. Outputs from this procedure include AIC and AICc.

AICc can be calculated from AIC via the following relation:

$$\text{AICc} = \text{AIC} + \frac{2k(k+1)}{n-k-1}$$

If a model with $3$ parameters is considered, then $k = 3$, and if $5$ data points are used in the fitting then $n = 5$. With these assumptions,

$$\frac{2k(k+1)}{n-k-1}=\frac{2\times 3(3+1)}{5-3-1}=24/1=24$$

The denominator of this expression would be zero for $4$ data points.

I have performed an analysis with 5 data points. The value of AICc should be AIC + 24. In this instance NonlinearModelFit calculated AICc = Infinity.

Is this an error or am I missing something?