Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Hypothesis estimating

The estimated VSS and EPD allow for the observation of the tip diffraction effects (phase inversion - Atp = 180° - for the direct and mirror diffraction echoes) for all selected Ascan signals. This proves the plane nature of the OSD and confirm our initial hypothesis. [Pg.178]

The second type of error occurs when the null hypothesis is retained even though it is false and should be rejected. This is known as a type 2 error, and its probability of occurrence is [3. Unfortunately, in most cases [3 cannot be easily calculated or estimated. [Pg.84]

Basically the test for whether the hypothesis is true or not hinges on a comparison of the within-treatment estimate s (with Vr = N — k degrees of freedom) with the between-treatment estimate. s (with Vt = k — I degrees of freedom). The test is made based on the F distribution for Vr and Vr degrees of freedom (Table 3-7). [Pg.506]

The algorithm for estimating the LDC and LDM for teehniques of test analysis with visual indieation is suggested. It ineludes the steps to eheek the suffieieney of experimental material [1]. The hypothesis ehoiee about the type of frequeney distribution in unreliable reaetion (UR) region is based on the ealeulation of eriteria eomplex Kolmogorov-Smirnov eriterion,... [Pg.307]

The goal of any statistical analysis is inference concerning whether on the basis of available data, some hypothesis about the natural world is true. The hypothesis may consist of the value of some parameter or parameters, such as a physical constant or the exact proportion of an allelic variant in a human population, or the hypothesis may be a qualitative statement, such as This protein adopts an a/p barrel fold or I am currently in Philadelphia. The parameters or hypothesis can be unobservable or as yet unobserved. How the data arise from the parameters is called the model for the system under study and may include estimates of experimental error as well as our best understanding of the physical process of the system. [Pg.314]

Mitchell s chemiosmotic hypothesis. The ratio of protons transported per pair of electrons passed through the chain—the so-called HV2 e ratio—has been an object of great interest for many years. Nevertheless, the ratio has remained extremely difficult to determine. The consensus estimate for the electron transport pathway from succinate to Og is 6 H /2 e. The ratio for Complex I by itself remains uncertain, but recent best estimates place it as high as 4 H /2 e. On the basis of this value, the stoichiometry of transport for the pathway from NADH to O2 is 10 H /2 e. Although this is the value assumed in Figure 21.21, it is important to realize that this represents a consensus drawn from many experiments. [Pg.692]

Fredkin s finite nature hypothesis makes no assumptions about the actual scale of space-time s discretization. It might be as large as current estimates of the... [Pg.665]

In passing we remark that there are well-known statistical methods of hypothesis testing and parameter estimation used in decisionmaking. Sequential analysis is a method of sampling used to decide whether to accept or reject a lot with defective items, or whether to continue sampling. Also, there are various statistical methods used in quality control of a manufacturing process, to decide on how much the quality should be improved to be acceptable. [Pg.316]

The main point of this exercise and considerations is that you can easily examine the feasibility of the desolvation hypothesis by using well-defined thermodynamic cycles. The only nontrivial numbers are the solvation energies, which can however be estimated reliably by the LD model. Thus for example, if you like to examine whether or not an enzymatic reaction resembles the corresponding gas-phase reaction or the solution reaction you may use the relationship... [Pg.214]

The entropic hypothesis seems at first sight to gain strong support from experiments with model compounds of the type listed in Table 9.1. These compounds show a huge rate acceleration when the number of degrees of freedom (i.e., rotation around different bonds) is restricted. Such model compounds have been used repeatedly in attempts to estimate entropic effects in enzyme catalysis. Unfortunately, the information from the available model compounds is not directly transferable to the relevant enzymatic reaction since the observed changes in rate constant reflect interrelated factors (e.g., strain and entropy), which cannot be separated in a unique way by simple experiments. Apparently, model compounds do provide very useful means for verification and calibration of reaction-potential surfaces... [Pg.221]

Madelimg s proof of the hypothesis of space lattices was an indirect one. The direct proof was made in 1912 by Max von Lane, who used two conjectrrres as a starting point for his experiment. The first conjectrrre concerned the newly discovered x-rays, whose wave length was estimated in the range between 12 rrm and 5 pm. The other conjecture concerned the distance between the lattice planes. Based on these two conjectures he birilt the hypothesis that the interaction x-rays with crystal lattices should lead to interference, what he coitld show in experimerrts. [Pg.229]

In order to formulate the statistical problem generally, let us return to the Arrhenius graph (Figure 5) and ask the question of how to estimate the position of the common point of intersection, if it exists (162). That is, in the coordinates x = T and y = log k, a family of 1 straight lines is given with the slopes bj (i = 1,2,..3) and with a common point of intersection (xq, yo). The ith line is determined by mj points (m > 2) with coordinates (xy, yjj) where j = 1,2,..., mj. Instead of the true coordinates yy, only the values yy = yy + ey are available, ey being random variables with a zero average value and a constant variance,. If the hypothesis of a common point of intersection is accepted, ey may be identified with the experimental error. [Pg.440]

Of course, Sqo Sq if the difference is significant, the hypothesis of a common point of intersection is to be rejected. Quite rigourously, the F test must not be used to judge this significance, but a semiquantitative comparison may be sufficient when the estimated experimental error 6 is taken into consideration. We can then decide whether the Arrhenius law holds within experimental error by comparing Soo/(mi-21) with 6 and whether the isokinetic relationship holds by comparing So/(ml — i— 2) with 5. ... [Pg.441]

It is estimated that there are in excess of 20 000 unique chemicals present as plant primary and secondary metabolites (Ohlrogge, 1994). The levels present in foods can vary quite considerably depending on the variety and on agronomic and environmental factors. To attribute benefits to any one chemical or group of chemicals seems a daunting task. Thus, in spite of intensive work in the last decade or so, there is still insufficient evidence with which to support the antioxidant hypothesis , or any other hypothesis, and to attribute... [Pg.222]


See other pages where Hypothesis estimating is mentioned: [Pg.448]    [Pg.340]    [Pg.448]    [Pg.340]    [Pg.172]    [Pg.177]    [Pg.178]    [Pg.650]    [Pg.696]    [Pg.210]    [Pg.22]    [Pg.64]    [Pg.65]    [Pg.199]    [Pg.330]    [Pg.176]    [Pg.223]    [Pg.548]    [Pg.368]    [Pg.105]    [Pg.239]    [Pg.113]    [Pg.292]    [Pg.209]    [Pg.224]    [Pg.250]    [Pg.437]    [Pg.446]    [Pg.452]    [Pg.452]    [Pg.424]    [Pg.37]    [Pg.290]    [Pg.128]    [Pg.112]    [Pg.83]    [Pg.92]    [Pg.91]    [Pg.22]   
See also in sourсe #XX -- [ Pg.218 ]




SEARCH



Brief review of estimation and hypothesis testing

Forecasting Model Error Estimation and Hypothesis Testing

Probability, hypothesis testing, and estimation

© 2024 chempedia.info