USING THE COMPUTER

EXCEL

• Excel can be used to compute exact or cumulative probabilities for particular values of discrete distributions including the binomial, Poisson, and hypergeometric distributions.
• Calculation of probabilities from each of these distributions begins with the Insert Function (f_x). To access the Insert Function, go to the Formulas tab on an Excel worksheet (top center tab). The Insert Function is on the far left of the menu bar. In the Insert Function dialog box at the top, there is a pulldown menu where it says Or select a category. From the pulldown menu associated with this command, select Statistical.
• To compute probabilities from a binomial distribution, select BINOM.DIST from the Insert Function's Statistical menu. In the BINOM.DIST dialog box, there are four lines to which you must respond. On the first line, Number_s, enter the value of x, the number of successes. On the second line, Trials, enter the number of trials (sample size, n). On the third line, Probability_s, enter the value of p. The fourth line, Cumulative, requires a logical response of either TRUE or FALSE. Place TRUE in the slot to get the cumulative probabilities for all values from 0 to x. Place FALSE in the slot to get the exact probability of getting x successes in n trials.