Truncated Rayleigh Lomax Distribution

DOI : 10.17577/IJERTV12IS010091

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Truncated Rayleigh Lomax Distribution

Hayder Kareem Hammood 1, Bushra Kadhum Awaad 2, Oday Hatem Jalil 3

1 Babylon Education Directorate, Babylon, Iraq.

2 College of Education of Pure Sciences, University of Kerbala, Kerbala, Iraq.

3 Assistant teacher – General Directorate of Education, Babylon Governorate.

Abstract:- The Truncated Rayleigh – Lomax distribution is introduced in this research. To do this, we interrupt the period of Rayleigh-Lomax to create a distribution with more flexibility and efficiency. Then we extracted the statistical and mathematical characters of the distribution, like, cumulative distribution, survival, density, Hazard, and cumulative Hazard functions. We also found the arithmetic mean, median, mode, order statistics, and moment-generating function extracted the Kurtosis and Skewedness, Variation Coefficients, and presented some analysis methods. Finally, we compared the new truncated Rayleigh-Lomax distribution with the original Rayleigh-Lomax distributions and some other distributions. The results showed that the truncated Rayleigh -Lomax distributions was better than the Rayleigh -Lomax distribution.

Keywords: Cumulative function, density, Reliability, moment generating function, reverse hazard, hazard, cumulative hazard function, mean and variance, mode, median, quintile, order statistics, moments, truncated Rayleigh Lomax distribution.

INTRODUCTION

We are sometimes required by design that is forced to truncate some of the distributions observations or delete them to take advantage of the time. In this case, only the sample taken from the truncated distribution is used for estimation purposes, and removing part of the possible values for this distribution, is done in one or two parts. Generally, any value outside the

period [, ] is ignored.

Since (; ) represents the truncated probability distribution function. That is, this function fulfills the conditions of

the probability density function, i.e. 0 and (; ) = 1 or ( ( = ; ) = 1). It is important to remember that

the truncation process changes the original distributions mean, variance, and other statistical measures.

The goal of discovering or developing the distribution is new because of its importance, usefulness, and practical and scientific reality in several areas of life, such as biostatistics or the analysis of survival function. So in this research, a new distribution was found: the truncate Rayleigh-Lomax distribution. This is done by truncating the period for the distribution of Rayleigh-Lomax.

  1. Truncated Rayleigh Lomax distribution.

    The distribution in which the period truncated at point a, in which a is a constant. i.e., All of the values chosen at random

    are in the range 0 < < .

  2. PDF and CDF of TRLD

    1 (1+)

    ( ; , , ) 22 (1 + )1 22

    (; , , ) = () () = 1 , 1 22(1+)

    (1)

    The pdf of the (TRLD) is given by

    1 & , , > 0

    1

    (1+)1 22(1+)

    Such as 2 2 = 1

    1

    1

    1 (1+) 22

    For the (TRLD), the corresponding plot to pdf is as follows:

    1

    0.9

    0.8

    b=0.9

    d=0.2,a=0.6

    d=0.6,a=1.1

    d=1.2,a=1.4

    d=1.4,a=1.6

    probability density function

    0.7

    0.6

    0.5

    0.4

    0.3

    0.2

    0.1

    0

    0 1 2 3 4 5 6

    x-axis

    Figure.1: p.d.f plotting of (TRLD), parameters b=0.9, theta=0.6,1.1,1.4,1.6 ; d=0.2,0.6,1.2,1.4

    theta=1.9

    1

    0.9

    0.8

    b=0.9,d=0.6

    b=1.2,d=0.8

    b=1.7,d=1.4

    b=2.2,d=1.9

    probability density function

    0.7

    0.6

    0.5

    0.4

    0.3

    0.2

    0.1

    0

    0 0.5 1 1.5 2 2.5 3 3.5 4

    x-axis

    Figure.2: p.d.f plotting of (TRLD), parameters theta=1.9, b=0.9,1.2,1.7,2.2 ; d=0.6,0.8,1.4,1.9

    beta=1.3

    1

    0.9

    0.8

    b=1.4,a=1.9

    b=1.1,a=1.6

    b=0.9,a=0.7

    b=0.6,a=0.4

    probability density function

    0.7

    0.6

    0.5

    0.4

    0.3

    0.2

    0.1

    0

    0 1 2 3 4 5 6

    x-axis

    Figure.3: p.d.f plotting of (TRLD), parameters beta=1.3, b=1.4,1.1,0.9,0.6 ; a=1.9,1.6,0.7,0.4

    Figures (1), (2) and (3) indicate that the TRPD family generates various shapes such as symmetrical, left skewed, right skewed and reversed- J

    1

    (1 + )1 22(1+)

    (; , , ) = (; , , ) = 22

    1

    1

    1

    1 22(1+) 1

    = 1 , & , , > 0 1 22(1+)

    (2)

    1

    1 22(1+)

    theta=4.7

    1

    0.9

    0.8

    cumulative distribution function

    0.7

    0.6

    0.5

    0.4

    0.3

    0.2

    0.1

    0

    b=0.4,d=0.3

    b=0.6,d=0.5

    b=0.8,d=0.7

    b=0.9,d=1.1

    0 0.5 1 1.5 2 2.5 3

    x-axis

    Figure.4: c.d.f plotting of (TRLD), parameters theta=4.7, b=0.4,0.6,0.8,0.9 ;d =0.3,0.5,0.7,1.1

    b=0.4

    1

    0.9

    0.8

    cumulative distribution function

    0.7

    0.6

    0.5

    0.4

    0.3

    0.2

    0.1

    0

    a=2.9,d=2.3

    a=2.1,d=1.9

    a=1.8,d=1.7

    a=1.6,d=1.5

    0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

    x-axis

    Figure.5: c.d.f plotting of (TRLD), parameters b=0.4, a=2.9,2.1,1.8,1.6 ; d =2.3,1.9,1.7,1.5

    beta=1.7

    1

    0.9

    cumulative distribution function

    0.8

    0.7

    0.6

    0.5

    a=1.4,b=1.3

    0.4 a=1.1,b=0.9

    a=0.8,b=0.7

    a=0.3,b=0.5

    0 0.5 1 1.5 2 2.5 3 3.5 4

    x-axis

    Figure.6: c.d.f plotting of (TRLD), parameters beta=1.7, a=1.4,1.1,0.8,0.3 ; b=1.3,0.9,0.7,0.5

    Figures (4), (5), and (6) show that when x and the parameters , , are increased, the cdf of the TRPD does not decrease. Figures (4), (5), and (6) demonstrate that the cdf of the TRPD does not decrease when and the parameters, , , are increased.

  3. Limitation of c.d.f and p.d.f

    lim (; , , ) = 0

    1

    (3)

    The distributions limitations are determined via:

    1 (1+)

    (1 + )1 22

    lim 22 = 0

    1

    1 (1+) 1 (1+)

    (1+)1 22 (1+)1 22

    lim (; , , ) = lim 2 2 = 2 2 > 0

    1 (1+) 1 (1+)

    1 22 1 22

    (4)

    Also,

    1 (1+)

    1 22

    1

    Because 1 22(1+)

    > 0 and

    1

    2

    1 (1+)

    22 (1 + )

    2 > 0

    1

    1 22(1+)

    lim (; , , ) = lim = 0

    1 1 1 (1+)

    1 22

    (5)

    As a result, this distributions c.d.f. is as follows:

    1

    1 22(1+)

    lim (; , , ) = lim 1 = 1

    1 22(1+)

    (6)

    Also,

    i.e 0

    (; , , ) 1

  4. Some Survival Functions

    In this section, some survival functons for the TRLD will be introduced.

    1. Survival Function

      1 1 1

      1 22(1+) 22(1+) 22(1+)

      () = 1 () = 1 1 = 1

      1 22(1+) 1 22(1+)

      (7)

      The survival function of TRLD is given by:

      Such as,

      1

      1

      lim () = lim

      22(1+)

      22(1+)

      = 1

      1

      1

      1 (1+)

      1 22

      12(1+)

      lim () = lim 2

      1 (1+)

      2

      2 = 0

      1 (1+)

      1 22

      That is 1) () 0, () 1 1

      2) () 1, () 0 0

      The plot of the () and the () for the(TRLD) as follows.

      0.9

      0.8

      0.7

      theta=3.9

      b=0.5,d=0.7

      b=0.6,d=0.8

      b=0.7,d=0.9

      b=0.9,d=1

      reliability function

      0.6

      0.5

      0.4

      0.3

      0.2

      0.1

      0

      0 0.5 1 1.5 2 2.5 3

      x-axis

      Figure.7: Plotting of () for (TRLD), parameters theta=3.9, b=0.5,0.6,0.7,0.9 ; d=0.7,0.8,0.9,1

      1

      0.9

      0.8

      b=0.4

      a=2.8,d=2.6

      a=1.9,d=1.7

      a=1.6,d=0.9

      a=0.9,d=0.8

      0.7

      reliability function

      0.6

      0.5

      0.4

      0.3

      0.2

      0.1

      0

      0 0.5 1 1.5 2 2.5 3 3.5 4

      x-axis

      Figure.8: Plotting of () for (TRLD), parameters b=3.9, a=2.8,1.9,1.6,0.9 ; d=2.6,1.7,0.9,0.8

      beta=3.8

      0.9

      0.8

      0.7

      a=0.4,b=0.3

      a=0.6,b=0.5

      a=0.8,b=0.7

      a=0.9,b=0.9

      reliability function

      0.6

      0.5

      0.4

      0.3

      0.2

      0.1

      0

      0 1 2 3 4 5 6 7 8 9 10

      x-axis

      Figure .9: Plotting of () for (TRLD), parameters beta=3.8, a=0.4,0.6,0.8,0.9 ; b=0.3,0.5,0.7,0.9

      The () of the TRPD is shown in Figures (7), (8), and (9) to be a decreasing function.

    2. Hazard Function

      1 (1+)

      ( ; , , ) 22 (1 + )1 22

      () = () = 1 1

      22(1+) 22(1+)

      (8)

      The hazard function for TRLD is given by:

      Figure.10: Plotting of () for (TRLD), parameter theta=3.2, b=3,4,5,6 ; d=0.5,1,1.5,2

      3.5

      a=1.6,d=1.5

      a=1.7,d=1.6

      b=2.6

      3 a=1.8,d=1.7

      a=1.9,d=1.8

      2.5

      hazard rate function

      2

      1.5

      1

      0.5

      0

      0 0.5 1 1.5 2 2.5 3 3.5 4

      x-axis

      Figure.11: Plotting of ()of the (TRLD) for parameter b=2.6, a=1.6,1.7,1.8,1.9 ; d=1.5,1.6,1.7,1.8

      beta=2.8

      30

      a=1.1,b=1.4

      a=1.4,b=1.6 25 a=1.5,b=1.7

      a=1.6,b=1.8

      hazard rate function

      20

      15

      10

      5

      0

      0 0.5 1 1.5 2 2.5 3 3.5 4

      x-axis

      Figure.12: Plotting of () for (TRLD), parameter beta=2.8, a=1.1,1.4,1.5,1.6 ; b=1.4,1.6,1.7,1.8.

    3. Reverse Hazard Function

      1 (1+)

      ( ; , , ) 22 (1 + )1 22

      () = (; , , ) = 1

      1 22(1+)

      (9)

      The reverse hazard function for TRLD is:

    4. The Cumulative Hazard Function

      1 1

      22(1+) 22(1+)

      () = () = 1

      1 22(1+)

      (10)

      The formulation for the TRLD cumulative hazard function is:

      Such as, , , , > 0

  5. Some properties of the TRLD :

      1. mode: Proposition1:

        2 1

        (2 ( 1)) 1

        =

        (11)

        The mode of the TRLD is.

        (, , , )

        = = 0

        (12)

        Proof:

        1

        2

        1 (1+)

        (, , , )

        =

        [

        22 (1 + ) 2

        1

        1 22(1+)

        ] = 0

        [ + 22 + ( 1)(1 + ) 1 (1 + ) ( 1 22(1+) )]=0

        1

        22

        ( 1) (1 +

        ) 22 (1 + )

        = 0

        2 1

        (2 ( 1)) 1

        =

        (13)

        ( 1) (1 +

        ) = 22 (1 + )

        1

      2. Quintile and Median:

    Proposition 2

    For the TRLD, the formula for the quintile and the median is as follows:

    1

    1

    [ 22 ( 1 [ 1 22(1+) ]] 1

    (14)

    =

    1 1

    [ 22 ( 1 1 + 22(1+)

    2 [ ]] 1

    =

    (15)

    Proof:

    From equation (3), obtain.

    1

    1 22(1+)

    1

    1 22(1+)

    = 1

    22

    1 (1+)

    = [ 1

    1 (1+) 22 ]

    1

    1

    22(1+)

    = 1 [ 1 22(1+) ]

    Take Ln to the two parties

    1

    1 (1+)

    22

    (1 + ) = (1 [ 1

    22 ])

    Then,

    1

    1

    =

    [ 22 ( 1 [ 1 22(1+) ])] 1

    (16)

    Changing = 1 in equation (16) for TRLDs median yields:

    2

    1

    1

    [ 22 ( 1 1 1 22(1+) ])] 1

    [

    =

    1 1

    [ 22 ( 1 1 + 22(1+)

    2 [ ]] 1

    =

    (17)

    2

    5.3.Moment Generation Function:

    Proposition3

    () = () 1) ()(+1)+

    (

    =0 =0 =0 =0

    (1)[()(+1)+ 1 (+1)+

    ( ) ]

    × 1

    (!)(!)(22)+1(1 22(1+))(( + 1) + )

    (18)

    The TRLD moment generation function is the formula:

    Proof:

    1

    2 (1 + )

    1 (1+) 22

    () = ( ) = 2

    1

    1

    1 22(1+)

    =0

    By using series expansion of get =

    So,

    !

    () = ( ) (

    1

    ) ()

    (+1) ( 1)

    1

    =0 =0 =0 =0

    (!)(!)(22)+1(1 22(1+) )

    × (+1)+1

    1

    () = ) 1) ()(+1)+

    ( (

    =0 =0 =0 =0

    (1)[()(+1)+ ( 1 )(+1)+]

    ×

    1

    (!)(!)(22)+1(1 22(1+) )(( + 1) + )

    (19)

    Then,

  6. Moments Theorem1:

    1

    () = ( ) ( ) ()(+1)

    =0 =0 =0

    (1)[()(+1)++1 (1)( + 1)(+1)+]

    ×

    1

    ! (22)+1[1 22(1+)] (( + 1) + )

    (20)

    The TRLDs moment with respect to the origin and moment with respect to the mean are as follows:

    1

    ( ) = ( ) ( ) ( ) () ()(+1)

    =0 =0 =0 =0

    (1)[()(+1)++1 1)(+1)++1

    ( ]

    × 1

    ! (22)+1[1 22(1+) ] (( + 1) + + 1)

    (21)

    r=1,2,3,.n

    Proof: Regarding the origin, the rth is:

    1

    22

    (1 + )1

    (1+)

    ( ) = (; , , ) = 22

    1

    1 22(1+)

    1

    1

    1 (1+)

    = 1

    22[1 22(1+) ]

    (1 + )1

    22

    Then,

    1

    1

    (1)

    () = ( ) (

    =0 =0 =0

    ) ()(+1)

    ! (22)+1[1

    1 (1+) 22 ]

    × (+1)+1

    1

    Then,

    1

    () = ( ) (

    =0 =0 =0

    ) ()(+1)

    (1)[()(+1)+ ( 1 )(+1)+]

    1

    ×

    ! (22)+1[1 22(1+)] (( + 1) + )

    (22)

    when r = 1,2

    1

    () = ( ) ( ) ()(+1)

    =0 =0 =0

    (1)[()(+1)+1 ( 1 )(+1)+1]

    ×

    1

    ! (22)+1[1 22(1+)] (( + 1) + 1)

    (23)

    1

    (2) = ( ) ( ) ()(+1)

    =0 =0 =0

    (1)[()(+1)+2 (1)(+1)+2]

    ×

    1

    ! (22)+1[1 22(1+)] (( + 1) + 2)

    (24)

    () = (2) [()]2

    (25)

    The mean's rth moment is provided via:

    1

    (1 + )1 22(1+)

    ( ) = ( ) 22

    1

    1

    1 22(1+)

    Where

    ( ) = (

    =0

    ) ()()

    1

    ( ) = ( ) ( ) ( ) () ()(+1)

    =0 =0 =0 =0

    (1)[()(+1)++1 ( 1 )(+1)+]

    ×

    1

    ! (22)+1[1 22(1+) ] (( + 1) + )

    (26)

    Therefore, mean's rth moment is provided via:

  7. Order Statistics

    Suppose that x1, x2,.,xn denoted a r.s for the size n from a TRLD with (; , , ) and (; , , ) in the equation (1) and (2) . Let 1, 2, . , denote the correlating orders statistical; so, the p.d.f of Xk:n is provided via:

    !

    1

    ,(, , , ) = (1)!()! (; , , )[(; , , )] [1 (; , , )]

    1 (1+)

    ! 22 (1 + )1 22

    ,(, , , ) = ( 1)! ( )! [ 1 ]

    1 (1+)

    22

    1 1 1 1

    1 22(1+) 22(1+) 22(1+)

    × [ 1 ] [ 1 ] 1 22(1+) 1 22(1+)

    (27)

    The rth order statistics p.d.f. is derived from the TRLDs p.d.f.

    1 1 1

    (1+)122(1+) (1+) (1+)

    (, , , ) = 2 2 22 22 ]1

    1, 1 [ 1

    (1+) (1+)

    1 22 1 22

    (28)

    So, we can define the median, maximum, and minimum p.d.f. as follows: 1- p.d.f of minimum if k=1:

    1

    (1 + )1 22(1+) 1 (1+)

    2 2 1 22

    ,(, , , ) = 1 [ 1 ]1 1 22(1+) 1 22(1+)

    (29)

    1. p.d.f of maximum if k=n:

      1 (1+) 1

      ! 22 (1 + ) 22 1 22(1+)

      +1,(, , , ) = [ ][ ][1

      ! ( 1)! 1 (1+) 1 (1+)

      1 22 1

      22

      1

      1 22(1+)

      1 ]1 1 22(1+)

      (30)

    2. p.d.f of median if k=m+1:

  8. Skewedness, Kurtosis, and Variation Coefficients

    In this section, we introduce and study Skewedness, kurtosis and variation of (TRLD) based on the moment as the following proposition.

    Proposition 4

    ( )3

    =

    3

    (31)

    The, variation coefficients, skewedness-kurtosis of the TRLD are presented via:

    Let =

    By equation ( 26), get

    3

    3

    1

    =

    ( ) ( ) (

    ) ()3 ()(+1)

    =0 =0

    =0 =0

    (1)[()(+1)++1 (1)(+1)+]

    1

    ×

    ! (22)+1[1 22(1+) ] (( + 1) + )

    2

    1

    = [

    =0 =0

    ( ) ( ) (

    =0 =0

    ) ()2 ()(+1)

    1

    (1)[()(+1)++1 ( )(+1)+]

    ( )4

    =

    4

    1

    ! (22)+1[1 22(1+)] (( + 1) + )

    (32)

    ×

    3

    ]2

    Let =

    By equation (26), get

    4

    4

    1

    =

    =0 =0

    ( ) ( ) (

    =0 =0

    ) ()4 ()(+1)

    1

    2

    (1)[()(+1)++1 ( )(+1)++1]

    × 1

    ! (22)+1[1 22(1+) ] (( + 1) + + 1)

    = [

    =0 =0

    2

    (

    =0 =0

    ) (

    1

    ) (

    ) ()2 ()(+1)

    ( ]

    (1)[()(+1)++1 1)(+1)++1

    =

    1

    ! (22)+1[1 22(1+) ] (( + 1) + + 1)

    (33)

    × ]2

    Let =

    2

    2

    1

    = [

    =0 =0

    ( ) ( ) (

    =0 =0

    ) ()2 ()(+1)

    1

    (1)[()(+1)++1 ( )(+1)++1]

    × 1

    1

    ]2

    1

    ! (22)+1[1 22(1+) ] (( + 1) + + 1)

    = ( ) (

    =0 =0 =0

    Proposition 5:

    ) ()(+1)

    (1)[()(+1)+1 (1)(+1)+1]

    1

    ×

    ! (22)+1[1 22(1+)] (( + 1) + 1)

    1 1

    = ( ) = ( ) ( )

    =0 =0 =0

    (+1)(1)[()(+1)1 1 (+1)1

    ( ) ]

    × 1

    ! (22)+1[1 22(1+)](( + 1) 1)

    (34)

    The harmonic mean is given by:

    Proof:

    1

    1

    1

    1 22 (1 + )

    1 (1+) 22

    = (

    ) =

    (; , , ) =

    1

    1

    1

    1 22(1+)

    1 (1+)

    = 1

    22[1

    (1+)]

    1(1 + )1

    22

    Thus,

    1

    22 1

    1

    (+1)

    ( ) =

    1

    22 [1 22(1+) ]

    ( ) (

    =0 =0 =0

    ) ()

    ( 1 )

    × 22

    !

    (+1)2

    Thus,

    1 1

    ( ) = ( ) ( )

    =0 =0 =0

    (+1)(1)[()(+1)1 ( 1 )(+1)1]

    ×

    1

    ! (22)+1[1 22(1+) ](( + 1) 1)

    (35)

    1

    Proposition 6:

    1

    = () = ( ) ( )

    =0 =0 =0

    1

    (+1)(1)[()(+1)1 ( 1 )(+1)+ ]

    2

    ×

    1

    ! (22)+1[1 22(1+) ](( + 1) + 1 )

    2

    Proof:

    (36)

    The formula for the geometrical mean is:

    = ( ) = 1 (; , , )

    1

    (1 + )1

    1 (1+)

    22

    1

    1

    = 2 22

    1

    1

    1 22(1+)

    = 1

    22(1+)

    2(1 + )1 22(1+)

    22[1

    ] 1

    Then,

    1

    () = ( ) ( )

    =0 =0 =0

    1

    (+1)(1)[()(+1)1 (1)(+1)+ ]

    2

    ×

    1

    ! (22)+1[1 22(1+) ](( + 1) + 1)

    2

    (37)

    () = 1 () , > 0 & 1

    1

    1

    (38)

  9. Renyi Entropy:Following is the Renyi entropy notation of the p.d.f. random variable x:

    Proposition 7:

    () = 1 [ () ) ()(+)

    1 (

    =0 =0 =0

    (1)[()(+)+1 ( 1 )(+)+1]

    × ]

    1

    ! (22)+[1 22(1+)] (( + ) + 1)

    Proof:

    1 (1+)

    (39)

    The Renyi entropy of x, when x is a random variable has a TRPD.

    1

    () = 1 log [

    22 (1 + )1

    1

    22

    ]

    (40)

    1

    1 22(1+)

    By integrating equation (40), get equation (39) by using the same steps in E(Xr).

  10. Estimation Methods

    There will be a discussion of several approaches for estimating TRLD's unknown parameters.

    1. Maximum Likelihood Estimation.

      Maximum likelihood estimation is employed to estimate the TRLDs unknown parameters. The p.d.f. the likelihood function is defined as follows:

      1

      (1+)

      (, , , ) =

      (22) =1(1 + )1

      1

      22

      =1

      1 22(1+)

      The likelihood function with the Ln of both sides is taken.

      1

      = + (22) + ( 1) (1 + ) (1 + )

      =1 22

      =1

      1

      (1 22(1+) )

      (41)

      1

      = + (1 + ) (1 + ) (1 + )

      =1 22

      =1

      1 1 (1+)

      (1 + ) (1 + ) 22

      22

      1

      1 22(1+)

      (42)

      Now, derive the equation (3.43) with respect to , b and

      1 1 (1+)

      2 1 3 (1 + ) 22

      = + (1 + )

      3 1 (1+)

      =1 1 22

      (43)

      1 1 (1+)

      ( 1) (1 + )1 2 (1 + ) 22

      = =1 =1 2

      (1 + ) 22 1 (1+)

      =1 1 22

      (44)

      1 1 (1+ )

      1 (1 + ) (1 + ) 2 2

      + (1 + ) (1 + ) (1 + ) 22

      22 1 (1+ )

      =1 =1 1 2 2

      = 0

      (45)

      Lastly, set every one of these equations equal to 0.

      =1

      ( 1)

      =1

      (1 + )1

      1 1 (1+ )

      2 1 (1 + ) 2 2

      + (1 + ) 3 = 0

      3 1 (1+ )

      =1 1 2 2

      1

      (46)

      (1+ )

      (1 + )

      22

      1

      2 2

      =1

      (1 +

      )

      22

      1

      1 (1+ ) = 0 (47)

      2

      2

      In order to determine the MLEs of the parameters , b and and, we solve equations (45) through (47) by using numerical

      techniques.

    2. Least Square Method (LS):

      Following is a working definition of the method. It is well known that.

      (( )) =

      ()

      +1

      Obtain the estimators by minimizing.

      2

      =1((()) +1)

      1

      1 22(1+)

      [ ( 1 ) ]2 1 22(1+) + 1

      =1

      (48)

      SO

      The could exist by deriving equation (48) concerning b.

      1

      1

      2 1 2

      1 (1+)

      (1+) (1+)

      (1 2 )( (1+) 2 )

      2[ ( 1

      2 2

      ) ] ×[

      3

      =1

      1

      1 (1+) 22

      +1

      (1

      1 (1+)

      22 )2

      (1

      1 (1+) 2 2

      )(

      1

      3

      (1 + )

      1 (1+) 2 2

      )

      ] = 0

      1 1

      1 (1+) (1 22(1+) )( 1 (1+) (1+) )

      22

      [ ( 1 2 2 ) ] ×[ 3

      =1 1 (1+) +1 1 (1+)

      1 22 (1 22 )2

      1 (1+) 1 1 (1+)

      (1 2 2 )( (1 + ) 2 2 )

      3 ] = 0

      1 (1+)

      (1 2 2 )2

      (49)

      Then,

      (1

      1 (1+)

      2 2 )2

      The

      could exist by deriving equation (48) concerning .

      1 (1+ )

      1 (1+ )

      2

      2[ ( 1

      1 (1+ )

      2

      (1 22

      ) ] × [

      )( (1+ )1 22 )

      2

      2

      =1

      1

      1 (1+ ) 22

      +1

      1

      1 (1+ )

      (1 22 )2

      1

      (1

      (1+ ))( (1 + )1

      (1+ ))

      22

      22

      1

      22

      ] = 0

      Then

      (1 22(1+ ))2

      1 (1+ ) 1 (1+ )

      12(1+ ) (1 22 )( (1+ )1 22 )

      2[ ( 1 2 ) ] × [ 2 2

      =1 1 (1+ ) +1 1 (1+ )

      1 22 (1 22 )2

      1 1

      (1 (1+ ))( (1 + )1 (1+ ))

      22 22

      22 ] = 0

      1

      (1 (1+ ))2

      22

      The can be found by deriving the equation (48) with respect to .

      1 1

      (50)

      12(1+)

      2(1+)

      1

      (1+)

      2

      2

      2[ ( 1

      2

      ) ] × [(1 2

      ) (

      2

      2

      (1 + ) (1 + ) )

      =1

      1

      1 (1+) 22

      1

      +1

      1 (1+ )

      (1 22

      )2

      1

      22

      (1

      (1+) )( 1

      22

      2 2

      (1 + ) ln (1 + )

      1

      (1+)

      )

      ] = 0

      1 1

      12(1+) ( 1 2(1+) ) 1 ( 1 + ) (1 + ) 2(1+) )

      [ (1 2 ) ] × [ 2 ( 2

      22

      =1 1

      (1+) +1 1 (1+ )

      1 22 (1 22 )2

      1 1

      (1 (1+) )( 1 (1 + ) l (1 + ) (1+))

      22 2 2

      22 ] = 0

      1

      (1 (1+ ))2

      22

      (51)

      Then,

      22

      (1

      (1+ ) )2

      Equations (49) through (51) have numerical solutions.

  11. Application

Data set 1: have data set represents the lifetime of 51 devices [23] the data set is 0.1,0.2,1,1,1,1,1,2,3,6,7,1,1,12,18,18,18,18,18,21,32,36,40,45,46,47,50,55,

60,63,63,67,67,67,67,72,75,75,79,82,82,84,84,84,85,85,85,85,85,86,86.

= 2 + 2 ,

(52)

Then compares the proposed method to the truncated Rayleigh Lomax distribution, the RLD, the LD, and the RPD, and it applies the MLE method to the dataset (TRPD). These metrics (CAIC, AIC, BIC, and HQIC) are used to make the model selection.

= 2 + (),

(53)

= 2 + 2(log())

(54)

= 2 + 2

1

(55)

Table (1) displays the model-level estimates (MLEs) for the data models, while Table (2) provides numerical amount for the

model-chosen statistical (AIC, , CAIC, BIC, and HQIC). Based on Table (2), the (TRLD) model provides the smallest

representation of the data set due to its small amount for the criteria CAIC, BIC, AIC, and HQIC.

Table 1. Data-based estimates of various parameters.

Models

Parameters Estimation

TRPD(x;,q,w)

=0.66

=20.247

=10.959

R-LD(x;,,b)

=0.844

=12.7726

=9.738

LD(x;,)

=1.08

=20.744

R-PD(x;p,b,)

=0.172

=0.627

=0.419

TRLD(x;,b)

= 0.859

= 2.987

= 5.617

Models

AIC

BIC

HQIC

CAIC

TRPD(x;,b,p)

-217.7661

441.5321

447.2682

443.7164

442.0588

R-LD(x;,,b)

-238.5086

495.0171

504.7532

497.2494

495.5388

LD(x;,)

-248.2744

502.5487

508.2848

504.7330

503.0704

R-PD(x;p,b,)

-287.7194

581.4387

587.1748

583.6230

581.9604

TRLD(x;,,b)

-239.2239

484.4478

490.1839

486.6321

484.9695

Table 2. , CAIC, BIC, AIC, and HQIC Data Set statistics values.

By comparing the results in Tables (1) and (2), we conclude that the truncated Rayleigh-Pareto distribution is preferable to Rayleigh-Lomax distribution Lomax distributions, truncated Rayleigh-Lomax distributions, and Rayleigh-Pareto distributions. This is because the (TRPD) and (TRLD) distributions have the smallest values for the (BIC), (AIC), (HQIC), and (CAIC) compared to the other distributions.

  1. CONCLUSIONS

    The current study presents a truncated Rayleigh – Pareto distribution (TRPD) for three parameters. In addition to the stress strength reliability pdf and cdf, distribution pdf and cdf are also located. Mod, the moment generating function, the median, the quintile, the mean and variance, the moments, the geometric mean, the harmonic mean, and the order statistics were among the data we retrieved. Essential estimating techniques were also used. It is observed that the (TRPD) was preferable to other distributions we considered.

  2. FUTURE WORK The current research suggests the following future works:

  1. Split the amputated period into (n) of the periods.

  2. Comparison of estimation methods.

  3. Use other new methods to estimate parameters.

  4. Find the parameters for the (TRPD) by numerical methods

  5. Find new distributions by truction.

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