145,550 research outputs found
Maximally selected chi-square statistics and umbrella orderings
No full textBinary outcomes that depend on an ordinal predictor in a non-monotonic way are common in medical data analysis. Such patterns can be addressed in terms of cutpoints: for example, one looks for two cutpoints that define an interval in the range of the ordinal predictor for which the probability of a positive outcome is particularly high (or low). A chi-square test may then be performed to compare the proportions of positive outcomes in and outside this interval. However, if the two cutpoints are chosen to maximize the chi-square statistic, referring the obtained chi-square statistic to the standard chi-square distribution is an inappropriate approach. It is then necessary to correct the p-value for multiple comparisons by considering the distribution of the maximally selected chi-square statistic instead of the nominal chi-square distribution. Here, we derive the exact distribution of the chi-square statistic obtained by the optimal two cutpoints. We suggest a combinatorial computation method and illustrate our approach by a simulation study and an application to varicella data
Vertex transitive graphs G with chi(D)(G) > chi(G) and small automorphism group
No full textFor a graph G and a positive integer k, a vertex labelling f : V (G) -> {1, 2,...,k} is said to be k-distinguishing if no non-trivial automorphism of G preserves the sets f(-1) (i) for each i epsilon {1,...,k}. The distinguishing chromatic number of a graph G, denoted chi(D)(G), is defined as the minimum k such that there is a k-distinguishing labelling of V (G) which is also a proper coloring of the vertices of G. In this paper, we prove the following theorem: Given k epsilon N, there exists an infinite sequence of vertex-transitive graphs G(i) = (V-i, E-i) such that 1. chi(D)(G(i)) > chi(G(i)) > k, 2. vertical bar Aut(G(i))vertical bar < 2k vertical bar V-i vertical bar, where Aut(G(i)) denotes the full automorphism group of G(i). In particular, this answers a question posed by the first and second authors of this paper
chi(D)(G), vertical bar Aut(G)vertical bar, and a variant of the Motion Lemma
No full textThe Distinguishing Chromatic Number of a graph G, denoted chi(D)(G), was first defined in [5] as the minimum number of colors needed to properly color G such that no non-trivial automorphism phi of the graph G fixes each color class of G. In this paper, 1. We prove a lemma that may be considered a variant of the Motion lemma of [15] and use this to give examples of several families of graphs which satisfy chi(D)(G) = chi(G) + 1. 2. We give an example of families of graphs that admit large automorphism groups in which every proper coloring is distinguishing. We also describe families of graphs with (relatively) very small automorphism groups which satisfy chi(D)(G) = chi(G) + 1, for arbitrarily large values of chi(G). 3. We describe non-trivial families of bipartite graphs that satisfy chi(D)(G) > r for any positive integer r
Zingari in fiera : Chi vuol la zingarella;
No full textArie Antiche reccolte per cura di A. Parisotti, Chi vuol la zingarella, canzone di G. Paisiello (1741-1816), G. Ricordi & C., Milano;5195
Graduate recital, piano. Chi, C.-H., 1992
No full textRecorded during a live performance at Dalton Center Recital Hall, Western Michigan University, Kalamazoo, Michigan, May 6, 1992, 8:00 p.m., the 545th concert of the School of Music's 1991-1992 season.Chia-Hui Chi, piano.In partial fulfillment of the requirements of the Master of Music degree in piano performance, Western Michigan University, 1992.Information from performance program.Piano sonata, op. 53 / Ludwig van Beethoven -- Ballade in G minor for piano, op. 23 / Frederic Chopin -- Third sonata / Paul Hindemith
On the functional equation H [tau (F,G), chi (F,G)] = H (F,G).
No full textIn this paper we solve the functional equation H [tau(F,G), chi (F,G)] = H (F,G) where the unknowns tau and chi are two semigroups on a space of distribution functions, and H is a given pointwise binary operation on this space satisfying some regularity condition
Understanding Urban Demand for Wild Meat in Vietnam: Implications for Conservation Actions
No full textVietnam is a significant consumer of wildlife, particularly wild meat, in urban restaurant settings. To meet this demand, poaching of wildlife is widespread, threatening regional and international biodiversity. Previous interventions to tackle illegal and potentially unsustainable consumption of wild meat in Vietnam have generally focused on limiting supply. While critical, they have been impeded by a lack of resources, the presence of increasingly organised criminal networks and corruption. Attention is, therefore, turning to the consumer, but a paucity of research investigating consumer demand for wild meat will impede the creation of effective consumer-centred interventions. Here we used a mixed-methods research approach comprising a hypothetical choice modelling survey and qualitative interviews to explore the drivers of wild meat consumption and consumer preferences among residents of Ho Chi Minh City, Vietnam. Our findings indicate that demand for wild meat is heterogeneous and highly context specific. Wild-sourced, rare, and expensive wild meat-types are eaten by those situated towards the top of the societal hierarchy to convey wealth and status and are commonly consumed in lucrative business contexts. Cheaper, legal and farmed substitutes for wild-sourced meats are also consumed, but typically in more casual consumption or social drinking settings. We explore the implications of our results for current conservation interventions in Vietnam that attempt to tackle illegal and potentially unsustainable trade in and consumption of wild meat and detail how our research informs future consumer-centric conservation actions
Student Recital: Mi H. Chi, piano
No full textSonata in B Flat Major, K.333, Wolfgang Amadeus Mozart (1756-1791) -- Variations Serieuses, Op. 54, Felix Mendelssohn (1809-1847) -- Cycles for Piano, Paul Cooper (1926-) -- Impromptu in G flat Major, Op. 51, Frédéric Chopin (1810-1849) -- Etude in G flat Major, Op. 25, No. 9, Frédéric Chopin (1810-1849) -- Etude in A flat Major, Op. 25, No. 1, Frédéric Chopin (1810-1849) -- Ballade in G Minor, Op. 23, Frédéric Chopin (1810-1849
Comparison of electrical activity of lateral and medial stabilizers of the patella and further diagnostically relevant risk factors in athletes with and without patellofemoral pain and in a Tai Chi group
No full textKhoshraftar Yazdi N. Comparison of electrical activity of lateral and medial stabilizers of the patella and further diagnostically relevant risk factors in athletes with and without patellofemoral pain and in a Tai Chi group. Bielefeld (Germany): Bielefeld University; 2010.Patellofemoral pain syndrome (PFPS) is a term for a variety of pathologies or anatomical abnormalities leading to a type of anterior knee pain and is the most common single diagnosis among runners and in sport medicine centers. Despite this high incidence, the exact cause of these disorders remains enigmatic.
The major complain of patients with PFPS is retropatellar pain during activities such as running, squatting, going up and down stairs, prolonged sitting, cycling, and jumping.
Some of risk factors in athletes with PFPS were considered and compared with athletes without PFPS in the present study. In addition, since Tai Chi (TC) helps or reduces the load on the lower limbs joints, particularly in knee, a TC group was chosen to compare with the two other groups
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