Search results for "Block design"

Examples of additive designs

2012

In this paper we present some additive designs.

Four-subtest short-form of the WAIS-IV for assessment of patients diagnosed with schizophrenia.

2021

Abstract Introduction The present study aimed to obtain a short form of the Spanish version of the WAIS-IV for patients diagnosed with schizophrenia that requires about half an hour to be administered. The reduced test can be very useful in clinical and research settings when an estimation of the intelligence quotient (IQ) is required to decide about intervention programs or to describe the sample. Materials and methods A sample of 143 patients participated in the study, 91 out of them were the test group, and the other 52 were used for a cross-validation analysis. To increase the content validity, the decision was made to create a short form composed of a subtest of each of the four cognit…

Über die Schnittzahlen mehrfach balancierter blockpläne

1991

Abstract For a finite incidence structure D with a set X of blocks let [ X ] be the number of points common with all blocks contained in X . We define the functions M(t)(B1,…; B1)=ΣB [B1, B]…[B1,B], and, for every partition ϖ = ϖ1,…,ϖ1) of t, the function Mϖ(B1,…,B1) = Σ Πm [Bi | i ϵ Rm], sum over all decompositions {l, …, t} = R1, ⊃ … ⊃ Rl, |Rm| = ϖm. We show: If D is t-fold balanced, then M(t) = Σϖ cϖMϖ, where the, coefficients cϖ are linear combinations of the parameters b1,…,bt, the constant numbers of blocks through any l,…, t distinct points. Conversely, if the rank of the b × b-matrix ([B, B∗])B,B∗ is equal to the number ν of points and M(t) is a rational linear combination of the fu…

An algebraic representation of Steiner triple systems of order 13

2021

Abstract In this paper we construct an incidence structure isomorphic to a Steiner triple system of order 13 by defining a set B of twentysix vectors in the 13-dimensional vector space V = GF ( 5 ) 13 , with the property that there exist precisely thirteen 6-subsets of B whose elements sum up to zero in V , which can also be characterized as the intersections of B with thirteen linear hyperplanes of V .

A note about 2-(v,5,lambda) designs

2010

Estimation Of The Genetic Parameters Of Eight Soybean Varieties In The Wasegi Village At Prafi District Manokwari Regency

2020

This study aims to estimate genetic parameters including genetic diversity coefficient, phenotypic diversity coefficient, heritability value, and the correlation between the character of plants from eight soybean varieties. The research was conducted from August to December 2017, in the Wasafi Village of Prafi District, Manokwari Regency. The study was designed using Randomized Block Design (RBD) with 8 treatments of soybean varieties. Each treatment was repeated 4 times, to obtain 32 experimental units. The data obtained were analyzed using ANOVA and if it had a significant effect, it was further tested using the Duncan Multiple Range Test (DMRT) at the 95% level, through the Costat progra…

Short Form of Spanish Version of the WISC–IV for Intelligence Assessment in Elementary School Children

2014

In educational settings, quick assessments of intelligence are often required to screen children with potential special needs. The WISC–IV is administered individually and takes between one and two hours to complete. Given its widespread use in Spain, a short-form of the Spanish version is likely to be of use to professionals. The goal of this research was to develop a short form of the WISC–IV that can be performed in approximately half an hour. Data obtained in 100 elementary school children were analyzed following the criteria of Resnick and Entin (1971). The results showed that the most accurate estimation of intelligence was achieved with a combination of the Vocabulary, Block Design,…

A note about additive designs

2008

On the 2-(25, 5, λ) design of zero-sum 5-sets in the Galois field GF(25)

2017

In this paper we consider the incidence structure ${\mathcal{D}}=({\mathcal{F}},{\mathcal{B}}_5^{0}),$ where ${\mathcal{F}}$ is the Galois field with $25$ elements, and ${\mathcal{B}}_5^{0}$ is the family of all $5$-subsets of $\mathcal F$ whose elements sum up to zero. It is known that ${\mathcal{D}}$ is a $2$-$(25,5,71)$ design. Here we provide two alternative, direct proofs of this result and, moreover, we prove that ${\mathcal{D}}$ is not a $3$-design. Furthermore, if ${\mathcal{B}}_5^{x}$ denotes the family of all $5$-subsets of $\mathcal F$ whose elements sum up to a given element $x \in \mathcal F,$ we also provide an alternative, direct proof that $({\mathcal{F}},{\mathcal{B}}_5^{x}…

On the additivity of block designs

2016

We show that symmetric block designs $${\mathcal {D}}=({\mathcal {P}},{\mathcal {B}})$$D=(P,B) can be embedded in a suitable commutative group $${\mathfrak {G}}_{\mathcal {D}}$$GD in such a way that the sum of the elements in each block is zero, whereas the only Steiner triple systems with this property are the point-line designs of $${\mathrm {PG}}(d,2)$$PG(d,2) and $${\mathrm {AG}}(d,3)$$AG(d,3). In both cases, the blocks can be characterized as the only k-subsets of $$\mathcal {P}$$P whose elements sum to zero. It follows that the group of automorphisms of any such design $$\mathcal {D}$$D is the group of automorphisms of $${\mathfrak {G}}_\mathcal {D}$$GD that leave $$\mathcal {P}$$P in…