The geometric probability density function builds upon what we have learned from the binomial distribution. In this case the experiment continues until either a success or a failure occurs rather than for a set number of trials. There are three main characteristics of a geometric experiment.
There are one or more Bernoulli trials with all failures except the last one, which is a success. In other words, you keep repeating what you are doing until the first success. Then you stop. For example, you throw a dart at a bullseye until you hit the bullseye. The first time you hit the bullseye is a "success" so you stop throwing the dart. It might take six tries until you hit the bullseye. You can think of the trials as failure, failure, failure, failure, failure, success, STOP.
In theory, the number of trials could go on forever. There must be at least one trial.
The probability,
p , of a success and the probability,
q , of a failure is the same for each trial.
p +
q = 1 and
q = 1 −
p . For example, the probability of rolling a three when you throw one fair die is
$\frac{1}{6}$ . This is true no matter how many times you roll the die. Suppose you want to know the probability of getting the first three on the fifth roll. On rolls one through four, you do not get a face with a three. The probability for each of the rolls is
q =
$\frac{\text{5}}{\text{6}}$ , the probability of a failure. The probability of getting a three on the fifth roll is
$\left(\frac{5}{6}\right)\left(\frac{5}{6}\right)\left(\frac{5}{6}\right)\left(\frac{5}{6}\right)\left(\frac{1}{6}\right)$ = 0.0804
X = the number of independent trials until the first success.
You play a game of chance that you can either win or lose (there are no other possibilities)
until you lose. Your probability of losing is
p = 0.57. What is the
probability that it takes five games until you lose? Let
X = the number of games you play until you lose (includes the losing game). Then
X takes on the values 1, 2, 3, ... (could go on indefinitely). The probability question is
P (
x = 5).
Try it
You throw darts at a board until you hit the center area. Your probability of hitting the center area is
p = 0.17. You want to find the probability that it takes eight throws until you hit the center. What values does
X take on?
1, 2, 3, 4, …
n . It can go on indefinitely.
A safety engineer feels that 35% of all industrial accidents in her plant are caused by failure of employees to follow instructions. She decides to look at the accident reports (selected randomly and replaced in the pile after reading)
until she finds one that shows an accident caused by failure of employees to follow instructions. On average, how many reports would the safety engineer
expect to look at until she finds a report showing an accident caused by employee failure to follow instructions? What is the probability that the safety engineer will have to examine at least three reports until she finds a report showing an accident caused by employee failure to follow instructions?
Let
X = the number of accidents the safety engineer must examine
until she finds a report showing an accident caused by employee failure to follow instructions.
X takes on the values 1, 2, 3, .... The first question asks you to find the
expected value or the mean. The second question asks you to find
P (
x ≥ 3). ("At least" translates to a "greater than or equal to" symbol).
Questions & Answers
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
In this morden time nanotechnology used in many field .
1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc
2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc
3- Atomobile -MEMS, Coating on car etc.
and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change .
maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world