STEP-BY-STEP TECHNOLOGY GUIDE: Poisson Distribution

TI-83/84

  • Step 1 Press 2nd DISTR, select poissonpdf(, and press ENTER.
  • Step 2 Enter the value of the mean μ, then a comma, then the number of occurrences X, and then). Press ENTER.

EXCEL

  • Step 1 Select cell A1. Click the Insert Function icon fx. For “Search for a function,” type Poisson and click Go.
  • Step 2 For “Select a function,” select POISSON and click OK.
  • Step 3 For X, enter the number of occurrences X for Mean, enter the value of the mean μ; and for Cumulative, type false. Click OK.

MINITAB

  • Step 1 Click Calc > Probability Distributions > Poisson…
  • Step 2 Select Probability. For Mean, enter the value of the mean μ. Select Input constant and enter the number of occurrences X.
  • Step 3 Click OK.

SPSS

  • Step 1 Enter any number into the first element of the spreadsheet.
  • Step 2 Select Transform > Compute Variable…. Under Target Variable, enter the name of your variable. Under Function group, select PDF and Noncentral PDF. Under Functions and Special Variables, double-click Pdf.Poisson. Replace the two question marks in Numeric Expression with the number of occurrences X and the mean μ, in that order.
  • Step 3 Click OK and OK. Minimize the output window.

JMP

  • Step 1 File > New > Data Table. Double-click the first element of Column 1. Right-click the header of Column 1 and select Column Info….
  • Step 2 Under Column Properties, select Formula then Edit Formula.
  • Step 3 Click Functions (grouped) > Discrete Probability, then select Poisson Probability. Replace lambda with the mean μ and k with number of occurrences X.
  • Step 4 Click OK then OK.

CRUNCHIT!

  • Step 1 Click Distribution Calculator > Poisson.
  • Step 2 For lambda, enter the mean μ.
  • Step 3 Select = from the drop-down menu next to P(X and enter the number of occurrences X in the box beside it. Click Calculate.