Sample size correction factors for indentation on asphalt bitumens

Abstract Using a continuous exposure variable that is measured with random error in a univariable linear regression model leads to regression dilution bias: the observed association between the exposure and outcome is smaller than it would be if the true value of the exposure could be used. A repeatability sub-study, where a sample of study participants have their data measured again, can be used to correct for this bias. It is important to perform a sample size calculation for such a sub-study, to ensure that correction factors can be estimated with sufficient precision. We describe how a previously published method can be used to calculate the sample size from the anticipated size of the correction factor and its desired precision, and demonstrate this approach using the example of the cross-sectional studies conducted as part of the International Project on Cardiovascular Disease in Russia study. We also provide correction factors calculated from repeat data from the UK Biobank study, which can be used to help plan future repeatability studies.

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A sample size correction for Pearson chi-square in 2???2 contingency tables.

Psychological Bulletin ◽

10.1037/0033-2909.91.2.418 ◽

1982 ◽

Vol 91 (2) ◽

pp. 418-423 ◽

Cited By ~ 25

Author(s):

Howard M. Rhoades ◽

John E. Overall

Keyword(s):

Sample Size ◽

Contingency Tables ◽

Chi Square ◽

Size Correction

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A Correction for Biasing Effects of Pilot Sample Size on Sample Size Determination

Journal of Marketing Research ◽

10.1177/002224378702400309 ◽

1987 ◽

Vol 24 (3) ◽

pp. 319-321 ◽

Cited By ~ 4

Author(s):

Ronald E. Shiffler ◽

Arthur J. Adams

Keyword(s):

Pilot Study ◽

Sample Size ◽

Random Variable ◽

Sample Size Determination ◽

Size Determination ◽

Correction Factors ◽

Biasing Effects ◽

Pilot Sample

When a pilot study variance is used to estimate σ2 in the sample size formula, the resulting [Formula: see text] is a random variable. The authors investigate the theoretical behavior of [Formula: see text]. Though [Formula: see text] is more likely to underachieve than overachieve the unbiased n, correction factors to balance the bias are provided.

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Comments on James' Methodological Issues Concerning Analysis of Archaeofaunal Recovery and Screen Size Correction Factors

Journal of Archaeological Science ◽

10.1006/jasc.1998.0352 ◽

1999 ◽

Vol 26 (9) ◽

pp. 1181-1182 ◽

Cited By ~ 4

Author(s):

Brian S Shaffer ◽

Barry W Baker

Keyword(s):

Correction Factors ◽

Methodological Issues ◽

Screen Size ◽

Size Correction

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Climate and size correction in European Union’s Waste Framework Directive and R1 energy efficiency criteria

Waste Management & Research ◽

10.1177/0734242x18782738 ◽

2018 ◽

Vol 36 (8) ◽

pp. 670-688 ◽

Cited By ~ 1

Author(s):

Kazi Mohammed Rayatul Hoque ◽

Cagil Ozansoy ◽

Murat Fahrioglu

Keyword(s):

European Union ◽

Energy Efficiency ◽

Correction Factor ◽

Correction Factors ◽

The European Union ◽

Size Correction ◽

Recovery Status ◽

Energy From Waste ◽

Case Based

This article presents an analysis on the use of the R1 formula to determine the recovery status of some energy from waste plants. Detailed R1 computations are provided to demonstrate the application of R1 guidelines in incineration and gasification facilities. Climate and size correction methods are proposed in consideration of the disadvantage faced by smaller-sized energy from waste plants or those located in warmer regions in meeting the set threshold. A key highlight is the case-based application of climate and size correction factors to three case study plants in scaling the R1 value in consideration of external variants. The proposed size and climate correction factors are compared with the climate correction factor defined in the Waste Framework Directive of the European Union. The application of the proposed correction factors lead to conservative R1 scaling when compared with the application of the Waste Framework Directive climate correction factor. The introduction of the size correction factor addresses an important gap in the current Waste Framework Directive.

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