0
Probability
The probability of a certain event is a number expressing the likelihood that a specific event will occur, expressed as the ratio of the number of actual occurrences to the number of possible occurrences. In mathematics, it is a measure of how often an event will happen and is the basis of statistics.
14,643 Questions
What is the probability of rolling the same number 4 times?
The first number doesn't matter, just that the last three are the same as the first.
P(rolling the same as the number before) = 1/6
P(rolling the same number as the first three times = (1/6)3 = 1/216
2 examples how the theory of probability is applied in real life situations?
how theory of probability used in real life
Given the mean of 259 and a standard deviation of 229.1 what is the z-score of the value 78?
(78-259)/229.1= -.79
Probability of two coins landing on tails?
the probabiluty of two coins landing on tails is 1/2 x 1/2 = 1/4, or one chance in four
Distribution would be centered at .14*128=17.92
The standard deviation of the distribution would be root(n(p(p-1)))=root(128*.14*.86)=3.92571013
Normal, unimodal
5 red candies 3 blue candies 4 yellow candies What is the probability of getting a red candy?
5 over 12
.0504
How do you make a marble sorter hopper release one marble at a time?
Carefully assemble the box of marbles to the box of marbles to the box of human fecies
Why mean and standard deviation are used for inferential statistics?
The following are the two main reasons.
- The first is that the inference to be made is usually (but not always) about the mean or standard deviation.
- Many probability distribution functions (but not all) can be defined in terms of these measures so identifying them is sufficient.
- They are well studied and their distributions are well known, along with tests for significance.
There are 8 out of 20 numbers that are prime, so 8/20, or 2/5.
What is approximate probability that a human offspring will be female?
50%, or half. Therefore, there is an equal chance that the offspring will be female.
What does a high figure of standard error mean?
A large degree of variation between individual measurements, in terms of the units used.
3 pictures are selected randomly from 5 pictures and arrange how many ways are there to arrange?
Assuming the question is that you have 5 pictures and want to know how many different ways you could put 3 on a wall from left to right:
There are 5 choices for the first picture; for each of these there are 4 choices for the second; and for each of these choices there are 3 choices for the third, meaning a total of:
5 x 4 x 3 = 60 ways that 3 pictures can be arranged from 5.
64/256
One-way independence.
The z score for the mean is always 0.
If yellow equals one fourth what would the probability of spinning a yellow 50 times?
1/4 raised to the power of 50; e.g. .2550.
Factors that determine sample size?
1. population to deal with in the sample
2. Location. ocation where the sample will be done
3. design. how the sample will be taken
4. result. how the outcome will be determined
What is the difference between convenience judgment and random sampling?
Non-probability or Judgement Samples has to do with a basic researcher assumptions about the nature of the population, the researcher assumes that any sample would be representative to the population,the results of this type of samples can not be generalized to the population(cause it may not be representative as the research assumed) and the results may be biased.
Probability or Random samples is a sample that to be drawn from the population such that each element in the population has a chance to be in the selected sample the results of the random samples can be used in Statistical inference purposes
