JP Carrascal jpcarrascal

## survey_sample_size.R
# Simple function to determine optimum sample size for a survey.
# A lot of websites provide online calculators, but here is the code so you can do it yourself in R.
# Source:
#     Krejcie, Robert V., and Daryle W. Morgan. "Determining sample size for research activities."
#     Educational and psychological measurement 30.3 (1970): 607-610.
#     https://journals.sagepub.com/doi/abs/10.1177/001316447003000308?journalCode=epma
#     Downloadable PDF: https://home.kku.ac.th/sompong/guest_speaker/KrejcieandMorgan_article.pdf
#
# The paper provides a table with chi-squared distribution values for 1 degree of freedom.
# R function qchisq() generates the right value from a given confidence level, so the table is not needed.
	# Simple function to determine optimum sample size for a survey.
	# A lot of websites provide online calculators, but here is the code so you can do it yourself in R.
	# Source:
	# Krejcie, Robert V., and Daryle W. Morgan. "Determining sample size for research activities."
	# Educational and psychological measurement 30.3 (1970): 607-610.
	# https://journals.sagepub.com/doi/abs/10.1177/001316447003000308?journalCode=epma
	# Downloadable PDF: https://home.kku.ac.th/sompong/guest_speaker/KrejcieandMorgan_article.pdf
	#
	# The paper provides a table with chi-squared distribution values for 1 degree of freedom.
	# R function qchisq() generates the right value from a given confidence level, so the table is not needed.