These functions provide the ability for generating probability density values, cumulative probability density values and moments about zero values for the Triangular Distribution bounded between [0,1].
dTRI(p,mode)
p | vector of probabilities. |
---|---|
mode | single value for mode. |
The output of dTRI
gives a list format consisting
pdf
probability density values in vector form.
mean
mean of the unit bounded Triangular distribution.
variance
variance of the unit bounded Triangular distribution
Setting \(min=0\) and \(max=1\) \(mode=c\) in the Triangular distribution a unit bounded Triangular distribution can be obtained. The probability density function and cumulative density function of a unit bounded Triangular distribution with random variable P are given by
$$g_{P}(p)= \frac{2p}{c} $$ ; \(0 \le p < c\) $$g_{P}(p)= \frac{2(1-p)}{(1-c)} $$ ; \(c \le p \le 1\) $$G_{P}(p)= \frac{p^2}{c} $$ ; \(0 \le p < c\) $$G_{P}(p)= 1-\frac{(1-p)^2}{(1-c)} $$ ; \(c \le p \le 1\) $$0 \le mode=c \le 1$$
The mean and the variance are denoted by $$E[P]= \frac{(a+b+c)}{3}= \frac{(1+c)}{3} $$ $$var[P]= \frac{a^2+b^2+c^2-ab-ac-bc}{18}= \frac{(1+c^2-c)}{18} $$
Moments about zero is denoted as $$E[P^r]= \frac{2c^{r+2}}{c(r+2)}+\frac{2(1-c^{r+1})}{(1-c)(r+1)}+\frac{2(c^{r+2}-1)}{(1-c)(r+2)} $$ \(r = 1,2,3,...\)
NOTE : If input parameters are not in given domain conditions necessary error messages will be provided to go further.
Horsnell, G. (1957). Economic acceptance sampling schemes. Journal of the Royal Statistical Society, Series A, 120:148-191.
Johnson, N. L., Kotz, S. and Balakrishnan, N. (1994) Continuous Univariate Distributions, Vol. 2, Wiley Series in Probability and Mathematical Statistics, Wiley.
Karlis, D. & Xekalaki, E., 2008. The Polygonal Distribution. In Advances in Mathematical and Statistical Modeling. Boston: Birkhuser Boston, pp. 21-33.
Available at: http://dx.doi.org/10.1007/978-0-8176-4626-4_2 .
Okagbue, H. et al., 2014. Using the Average of the Extreme Values of a Triangular Distribution for a Transformation, and Its Approximant via the Continuous Uniform Distribution. British Journal of Mathematics & Computer Science, 4(24), pp.3497-3507.
Available at: http://www.sciencedomain.org/abstract.php?iid=699&id=6&aid=6427 .
#plotting the random variables and probability values col <- rainbow(4) x <- seq(0.2,0.8,by=0.2) plot(0,0,main="Probability density graph",xlab="Random variable", ylab="Probability density values",xlim = c(0,1),ylim = c(0,3))#> [1] 0.0000000 0.3333333 0.6666667 1.0000000 1.3333333 1.6666667 2.0000000 #> [8] 1.8571429 1.7142857 1.5714286 1.4285714 1.2857143 1.1428571 1.0000000 #> [15] 0.8571429 0.7142857 0.5714286 0.4285714 0.2857143 0.1428571 0.0000000#> [1] 0.4333333#> [1] 0.04388889#plotting the random variables and cumulative probability values col <- rainbow(4) x <- seq(0.2,0.8,by=0.2) plot(0,0,main="Cumulative density graph",xlab="Random variable", ylab="Cumulative density values",xlim = c(0,1),ylim = c(0,1))#> [1] 0.000000000 0.008333333 0.033333333 0.075000000 0.133333333 0.208333333 #> [7] 0.300000000 0.396428571 0.485714286 0.567857143 0.642857143 0.710714286 #> [13] 0.771428571 0.825000000 0.871428571 0.910714286 0.942857143 0.967857143 #> [19] 0.985714286 0.996428571 1.000000000#> [1] 0.4333333#> [1] 0.04388889#> [1] 0.5