For 1sample Poisson rate, the hypotheses are as follows.
 Null hypothesis

H_{0}: λ = λ_{0} 
The population rate of occurrence (λ) equals the hypothesized rate of occurrence (λ_{0}). 
 Alternative hypothesis
 Select one of the following alternative hypotheses.
H_{1}: λ ≠ λ_{0} 
The population rate of occurrence (λ) differs from the hypothesized rate of occurrence (λ_{0}). 
H_{1}: λ > λ_{0} 
The population rate of occurrence (λ) is greater than the hypothesized rate of occurrence (λ_{0}). 
H_{1}: λ < λ_{0} 
The population rate of occurrence (λ) is less than the hypothesized rate of occurrence (λ_{0}). 