How to Calcualte "Effect Size" and "Effect Allele" of each SNP

Question

[Raju]

Hello Folks,

What is the meaning/definition of Effect Size and Effect Allele?

What data files are required to find the Effect Size and Effect Allele of each SNP?

I have .bed files & VCF file with me, how to calculate the "Effect Size" and "Effect Allele" of each SNP?

New to GWAS Analysis, any information much appreciated

Thanks in Advance!!