Data 2.2 4 6.7 5 10.9 15

Data Entry The data is a 2 column table of numbers, each row a separate test The columns are separated by white spaces (space or tab) Column 1 is the Reference or expected mean count λ. This must be a positive value, and can be a decimal number Column 2 is the observed count k. This must be a positive integer value Use Example or enter user data, then click button to run program

The results are displayed in a 4 column table.

• Columns 1 to 2 show the data as entered, for error checks
• Column 3 is the probability of observing k or less counts, if the expected count is λ
• Column 4 is the probability of observing k or more counts, if the expected count is λ
• Note the probability of exactly k count is included in both column 3 and 4, so that the two columns adds up to more than the total (1)

Steel RGD, Torrie JH Dickey DA (1997) Principles and Procedures of Statistics. A Biomedical Approach. The McGraw-Hill Companies, Inc New York. p. 558