Uncertainties in H0 : RANDOM ERRORS

• Cepheid Distance Scale

• Photometry ±0.05

• Extinction Treatment ±0.02

• Cepheid True Modulus ±0.06

• TF Distance Scale

• TF Magnitudes ±0.03

• Linewidth ±0.01

• Intrinsic Dispersion ±0.05

• Hubble Constant

• Cluster Velocities ~5%

Notes: