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Article Contents

ABSTRACT

1.INTRODUCTION

2.DESCRIPTION OF MAXIMUM LIKELIHOOD METHOD
2.1.Alternative Approaches to Peculiar Velocity-Density Comparison
2.2.VELMOD
2.2.1.Mathematical Details
2.2.2.Further Discussion of VELMOD Likelihood
2.2.3.Implementation of VELMOD

3.TESTS WITH SIMULATED GALAXY CATALOGS
3.1.Accuracy of beta-Determination
3.2.Accuracy of Determination of sigmav and wLG
3.3.TF Parameters Obtained from VELMOD
3.4.Properties of VELMOD Likelihood

4.APPLICATION TO MARK III CATALOG DATA
4.1.Sample Selection
4.2.Velocity Width Dependence of TF Scatter
4.3.Treatment of Virgo
4.4.Implementation of a Quadrupole Flow
4.5.Results
4.6.VELMOD Results Using 500 km s-1 Smoothing
4.7.Consistency of Mark III and VELMOD TF Relations

5.ANALYSIS OF RESIDUALS: DO PREDICTIONS MATCH OBSERVATIONS?
5.1.Sky Maps of VELMOD Residuals
5.2.Residual Autocorrelation Function
5.2.1.Using Residual Correlations to Identify Poor Fits Quantitatively

6.DISCUSSION
6.1.What is the Value of betaI?
6.1.1.Why Do VELMOD and POTIRAS Yield Different Values of betaI?
6.1.2.Effect of Cosmic Scatter
6.2.Do IRAS and TF Velocity Fields Agree?
6.2.1Comparison with Davis, Nusser, & Willick
6.2.2.Role of Quadrupole
6.3.What is the Value of Omega?
6.3.1.Nonlinear Analysis
6.3.2.Constraining Omega from Independent Estimates of bI
6.4.Summary

APPENDIX A. IRAS VELOCITY-DENSITY RECONSTRUCTION

APPENDIX B. RESIDUAL QUADRUPOLE

APPENDIX C. PROPERTIES OF STATISTIC chi2xi

REFERENCES