| Frequencies | Proportions | |||
|---|---|---|---|---|
| Success | Failure | Success | Failure | |
| Barcoding Practice | a | b | pa = a/(a + b) | pb = b/(a + b) |
| Comparison Practice | c | d | pc = c/(c + d) | pd = d/(c + d) |
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.