When can the pooled variance be used in CNR estimates in DWI?
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The pooled variance can be used in CNR estimates in DWI when the parameter of interest is the pooled variance . It is useful in optimum allocation when strata standard deviations are estimated and several of them are equal . Additionally, using a variance estimator based on one sample provides a more powerful test of capability than using a pooled variance estimator, based on the same number of observations, from many smaller samples . However, the use of pooled interaction error terms in repeated measurement analyses of variance may lead to seriously erroneous conclusions, especially when designs contain data sampled at short and long intervals . Pooled estimators, which combine statistical information from different samples, can be used to estimate parameters in various contexts, such as analysis of variance .
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| Papers (5) | Insight |
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Open access 01 Jan 2013 | The answer to the query is not present in the provided paper. The paper is about optimum stratification in the estimation of pooled variance, not about its use in CNR estimates in DWI. |
13 Citations | The answer to the query is not present in the provided paper. The paper is about the use of pooled interaction error terms in repeated measurement analyses of variance and does not discuss CNR estimates in DWI. |
Open access 01 Jan 2001 1 Citations | The answer to the query is not provided in the paper. The paper is about the use of pooled variance estimator in hypothesis testing procedures involving Cpm, not about CNR estimates in DWI. |
1 Citations | The provided paper does not mention anything about CNR estimates in DWI. |
| The provided paper does not mention CNR estimates in DWI. |
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