R/Gamma.R
fitGrassiaIIBin.Rd
The function will fit the Grassia II Binomial Distribution when random variables, corresponding frequencies and shape parameters are given. It will provide the expected frequencies, chi-squared test statistics value, p value, degree of freedom and over dispersion value so that it can be seen if this distribution fits the data.
fitGrassiaIIBin(x,obs.freq,a,b)
x | vector of binomial random variables. |
---|---|
obs.freq | vector of frequencies. |
a | single value for shape parameter a. |
b | single value for shape parameter b. |
The output of fitGrassiaIIBin
gives the class format fitGrIIB
and fit
consisting a list
bin.ran.var
binomial random variables.
obs.freq
corresponding observed frequencies.
exp.freq
corresponding expected frequencies.
statistic
chi-squared test statistics.
df
degree of freedom.
p.value
probability value by chi-squared test statistic.
fitGrIIB
fitted values of dGrassiaIIBin
.
NegLL
Negative Log Likelihood value.
a
estimated value for shape parameter a.
b
estimated value for shape parameter b.
AIC
AIC value.
over.dis.para
over dispersion value.
call
the inputs of the function.
Methods summary
, print
, AIC
, residuals
and fitted
can be used to
extract specific outputs.
$$0 < a,b$$ $$x = 0,1,2,...$$ $$obs.freq \ge 0$$
NOTE : If input parameters are not in given domain conditions necessary error messages will be provided to go further.
Grassia, A., 1977. On a family of distributions with argument between 0 and 1 obtained by transformation of the gamma and derived compound distributions. Australian Journal of Statistics, 19(2), pp.108-114.
No.D.D <- 0:7 #assigning the random variables Obs.fre.1 <- c(47,54,43,40,40,41,39,95) #assigning the corresponding frequencies #estimating the parameters using maximum log likelihood value and assigning it parameters <- EstMLEGrassiaIIBin(x=No.D.D,freq=Obs.fre.1,a=0.1,b=0.1) aGIIBin <- bbmle::coef(parameters)[1] #assigning the estimated a bGIIBin <- bbmle::coef(parameters)[2] #assigning the estimated b #fitting when the random variable,frequencies,shape parameter values are given. results <- fitGrassiaIIBin(No.D.D,Obs.fre.1,aGIIBin,bGIIBin) results#> Call: #> fitGrassiaIIBin(x = No.D.D, obs.freq = Obs.fre.1, a = aGIIBin, #> b = bGIIBin) #> #> Chi-squared test for Grassia II Binomial Distribution #> #> Observed Frequency : 47 54 43 40 40 41 39 95 #> #> expected Frequency : 55.02 42.36 39.08 38.51 39.78 43.39 52.13 88.74 #> #> estimated a parameter : 0.7285048 ,estimated b parameter : 2.025147 #> #> X-squared : 8.6999 ,df : 5 ,p-value : 0.1216 #> #> over dispersion : 0.2590043#> [1] 55.02 42.36 39.08 38.51 39.78 43.39 52.13 88.74#> [1] -8.02 11.64 3.92 1.49 0.22 -2.39 -13.13 6.26