alternative hypothesis

(redirected from Alternative Hypotheses)
Also found in: Dictionary, Financial, Encyclopedia.

hypothesis

 [hi-poth´ĕ-sis]
a supposition that appears to explain a group of phenomena and is advanced as a bases for further investigation.
alternative hypothesis the hypothesis that is formulated as an opposite to the null hypothesis in a statistical test.
complex hypothesis a prediction of the relationship between two or more independent variables and two or more dependent variables.
directional hypothesis a statement of the specific nature (direction) of the relationship between two or more variables.
Lyon hypothesis a hypothesis about development of X chromosomes in the embryo; see lyon hypothesis.
Monro-Kellie hypothesis [mun-ro´ kel´e] an explanation of the maintenance of intracranial pressure: The skull is viewed as a closed container housing brain tissue, blood, and cerebrospinal fluid; a change in any of these three components will affect the other two. If the volume added to the cranial vault is equal to the volume displaced, the intracranial volume will not change.
nondirectional hypothesis a statement that a relationship exists between two variables, without predicting the exact nature (direction) of the relationship.
null hypothesis the hyothesis that the effect, relationship, or other manifestation of variables and data under investigation does not exist; an example would be the hypothesis that there is no difference between experimental and control groups in a clinical trial.
hypothesis test the abstract procedure that is the theoretical basis of most statistical tests. A hypothesis test decides between two hypotheses, the null hypothesis (H0) that the effect under investigation does not exist and the alternative hypothesis (H1) that some specified effect does exist, based on the observed value of a test statistic whose sampling distribution is completely determined by H0. The decision is made to reject H0 and by implication to accept H1 when the test statistic falls within a given set of values called the critical region. This region is so determined that the probability of rejecting H0 when it is in fact true (a so-called Type I error, the reporting as significant results that are only the result of random variation and not a real effect), is set at a specified level (symbol α). When this level is set before the data are collected, usually at 0.05 or 0.01, it is called the significance level or α level. It is now more common to report the smallest α at which the null hypothesis can be rejected; this is called the significance probability or P value. The ability of the test to accept a true alternative (and thus to detect a real effect when it exists) is termed the power of the test. Note that no statistical test actually tests the H1.

al·ter·na·tive hy·poth·e·sis

in Neyman-Pearson testing of a hypothesis, the hypothesis or family of hypotheses about the numerical value of a parameter if and only if the null hypothesis is rejected as untenable.

alternative hypothesis

EBM
A statement that the means, variance, etc., of the samples being tested are not equal, which is the opposite of a null hypothesis.
 
Epidemiology
A hypothesis to be adopted if a null hypothesis proves implausible, where exposure is linked to disease.
 
Oncology
A hypothesis of tumour biology which holds that cancer is a systemic disease for which locoregional therapy is unlikely to improve survival statistics.
 
Statistics
A statement which is true if the null hypothesis is false; the type of test—left, right or two-tail—is based on the alternative hypothesis.

alternative hypothesis

Epidemiology A hypothesis to be adopted if a null hypothesis proves implausible, where exposure is linked to disease. See Hypothesis testing. Cf Null hypothesis.

alternative hypothesis

The possibility (which should always be borne in mind) that an explanation of a phenomenon or result, however apparently obvious, may not be correct. See also NULL HYPOTHESIS.
References in periodicals archive ?
Another problems we may encounter in the null-hypotheses testing is what is called the fallacy of transposed conditional, that is, we conclude the truth of the alternative hypothesis based on the rejection of the null-hypotheses but the alternative hypotheses may be rejected as well because we did not test it directly and therefore there are many other feasible alternative hypotheses once the null-hypotheses is rejected.
Whereas in United States, their auditors believe the impact of using CAATs is the auditor can formulate a range of alternative hypotheses for a particular potential misstatement in the subject matter and then test those hypotheses immediately using datasets drawn from the accounting information system.
A search for alternative hypotheses, including the previous viral hypothesis for Black Death, may not be necessary (2).
The papers and accompanying discussions in this volume address how heterogeneous beliefs interact with equilibrium leverage and potentially lead to leverage cycles, the validity of alternative hypotheses about the reason for the recent increase in foreclosures on residential mortgages, the credit rating crisis, quantitative implications for the evolution of the U.
First we state the research, null, and alternative hypotheses and the significance level required to reject the null hypothesis with 90% confidence.
Remember that for a (two-sided) superiority trial, the null and alternative hypotheses are [H.
The historiography of this topic is vast, involving a range of disciplines--archaeology, linguistics, anthropology, mythology, ethnography, history--producing a number of alternative hypotheses.
The results do not clearly differentiate between our two alternative hypotheses.
In general, the way Pekkanen structures his argument--that is, that the "political institutional" approach explains the development of Japan's civil society best because it most closely matches the historical narrative he lays forth--tends to preclude the consideration of alternative hypotheses.
10) Second, individual and panel LM t-statistics allow for breaks under the null and alternative hypotheses, which avoids the possibility of spurious rejections caused by size distortions (see Nunes, Newbold, and Kuan 1997; Lee and Strazicich 2001).
Thus, lacking the presumption of equivalence, "we must consider the likelihood that alternative hypotheses may account for the results.
They consider basic concepts such as null and alternative hypotheses, p-value, significance level, and power; and such topics as sample selection, linear regression, the analysis of variance, maximum likelihood, Bayes' theorem, meta-analysis, and the bootstrap.

Full browser ?