Microsoft Office Tutorials and References

In Depth Information

**BETAINV**

ALPHA
Is a parameter to the distribution and must be a positive number.

BETA
Is a parameter to the distribution and must be a positive number.

A
Is an optional lower bound to the inter val of
X
; is omitted, assumed to

be zero (0).

B
Is an optional upper bound to the inter val of
X
; if omitted, assumed to

be one (1).

For example,
=BETADIST(2,6,12,1,3)
equals
0.9282684
.

BETAINV

BETAINV
returns the inverse of the cumulative beta probability density function.

=BETAINV(probability,alpha,beta,A,B)

The
BETAINV
function takes the probability you predict and returns the X value in the

BETADIST
function. So, if the probability is 0.9282684, then the
BETAINV
function returns 2.

PROBABILITY
Is the probability you predict or expect.

ALPHA
Is a parameter to the distribution and must be a positive number.

BETA
Is a parameter to the distribution and must be a positive number.

A
Is an optional lower bound to the inter val of X; is omitted, assumed to

be zero (0).

B
Is an optional upper bound to the inter val of X; if omitted, assumed to

be one (1).

For example,
=BETAINV(0.9282684,6,12,1,3)
equals 2.

BINOMDIST

BINOMDIST
returns the individual term binomial distribution probability.

=BINOMDIST(number_s,trials,probability_s,cumulative)

The
BINOMDIST
function is used to find the probability that an outcome will occur
x
times in
n

performances of an experiment or trial. The trials are known as
Bernoulli trials
. The

BINOMDIST
function is used when:

■
The number of trials (or tests) is fixed.

■
Each repetition of the trial results in one of two possible outcomes—success or failure.

■
The trials are independent and performed under identical conditions.

■
Probability of success (denoted by
p) is constant throughout the experiment.

Represents the number of successes in trials; must be a positive

number but smaller than the number of trials.

NUMBER_S

Is the number of trials.

TRIALS

Is the probability of success on each trial; must be a positive

number less than 1.

PROBABILITY_S