Oct. 6, 2010 LAB #2
I. Calculating the Binomial Distribution: Flips of a Fair Coin ( # of trials)
Open Excel, In cell B3, type “Binomial 1 flip”
In cell B5 type “k” for the binomial variable, and in B6 type “0”
And in B7 type “1”
In cell C5 type “n” for the number of trials, and in C6 type “1” and in C7 type
In cell D5 type “p” for probability, select cell D6, go to the formula bar and
type “=”, insert function, choose function category ‘statistical” and function
name “binomial”, and hit OK.
In the dialog box, number s is the number of successes, select cell “B6”,
Trials is the number of trials, select cell “C6”, probability s is the probability
of a success, type in “0.5”, cumulative gives you an option of finding, for
example, the probability of zero heads, type in “false”, or the cumulative
distribution function, less than or equal zero heads, type in “true”. We will use
false. Hit OK. If needed, hit the “?’ button for more info on the dialog box.
For cell D6, we have p(k=0) = C
= 1!/(0!1!) * 0.50 =0.50.
Drag the lower right hand corner “handle” down through cell D7.
For a chart of the distribution, select cells B6 and B7, hold down the “ctrl”
key and select cells D6 and D7. Go to the insert menu and select “chart”, and
in the dialog box select “xy scatter” as the type. Hit the “next” button. Select
the “series in column” button, and hit “next”. Select the “titles” tab and for
chart title type “ Binomial; One Flip”, for the x axis type “Number of Heads”,
For the y axis type “Probability”. Select the legend tab and deactivate “show
legend”. Select the gridlines tab and deactivate “major gridlines” for the y
axis. Hit the “next” button and place the chart on a new sheet, and then the
“finish” button. Select the plot area and go to the format menu and select
“format plot area” and under area, hit the “none” button. Select the x axis by
clicking on it and go to the format menu and select ‘format axis”. In the dialog
box, select the scale tab and for maximum type in 1.0 and for major unit type