probability

  1. Z

    Gambling probability problem

    A slot machine works on inserting a $1 coin. If the player wins, the coin is returned with an additional $1 coin, otherwise the original coin is lost. The probability of winning is 1/2 unless the previous play has resulted in a win, in which case the probability is p < 1/2. If the cost of...
  2. J

    emperical rule

    does anyone understand this question? Thanks in advance!
  3. J

    joint probability

    I am not really sure how to calculate question C. Can anyone help me out? Thanks in advance!
  4. A

    How to find the probability of a sampling error made in estimating the population mean?

    Alright, I have been working on my statistics assignment since Monday and I only have two questions left, dealing with the probability of a sampling error. Unfortunately, I cannot find anything in my notes and only a brief example in my textbook that does not explain the concepts behind the...
  5. J

    normal distribution

    Hi everyone! I have a question about the answer of question 19a and e. question a: Find the probability that X is greater than 60. Why do they do 0,5 -0,3944 and not 1 - ...? Question e was: the probability is 0,05 that X is in the symmetric interval about the mean between which two numbers...
  6. J

    poisson distribition question

    Hello everyone, I don't really understand the answer of question a. The question was: Find the probability that on any given day there will be fewer than two breakdowns on this highwayduring the morning rush hour. Additional information: on average: 3,2 breakdowns per day occur. isn't it...
  7. M

    Defintion of a random variable

    I have read two defintions for a random variable. 1. It is a function from the set of all posisible outcomes to the real line. For example Y("male")=0 2. A variable where known probabilities are associated with sample outcomes. Which one is correct? Defintion 1 does not include a probability...
  8. M

    Support vs sample space

    I understand that the term support is not used in the same sense in mathamtics and statistics. However, I cannot really understand difference between support and sample space when it comes to statistics. Could you say that the support isa subset of the sample space, i.e. all sample points that...
  9. Y

    Probability question

    The govt. of ontario decided it would try to raise money by installing photo radar cameras on the 401 highway acros the top of Toronto. The camera would be set to record the speed of those travelling more that 135 km/h and send them a ticket for $200. It would only run the program between the...
  10. Y

    Am I using the binom.dist properly?

    Q -Stats classhas 60 students in it. The class lasts for three hours and the students ask questions at a rate of about 3 questions per hour. Model this situation with an appropriate binomial distribution and determine the probability of receiving more than 5 questions in a class. My answer...
  11. W

    Odds Ratio to Probability of Success

    We ran a logistic regression model with Passing the certification exam (0 or 1) as an outcome. We found that one of the strongest predictors is the student's program GPA, the highest the program GPA, the highest the odds of passing the certification exam. Standardized GPA: p-value < .0001, B...
  12. C

    Combined Probability

    How do I solve this problem? Four departments: PE (6 team members), QA (8 team members), EE (5 team members), and AS (28 team members). If 8 team members are randomly selected, what is the probability that you will: 1) Have at least one team member from each department 2) All AS team members...
  13. V

    Probability Question

    If you toss 100 fair coins (chance is 50% that it is heads) What is the chance that you will get 60 or more heads. Does anyone know how to calculate this probability? Thank you in advance!
  14. M

    Nonparametric data analysis

    I'm asking for advice. Topic of my research is brain iron accumulation. My task is the next . I have one dependent variable that is cathegorical and binominal(patient has the pathology or does not). And six independent variables that are continuous and nonpatametric. The question is :how can i...
  15. C

    Empirical Survivor Function (esf)

    From page 26, chapter 2 of the reference "Tableman, M., & Kim, J. S. (2003). Survival analysis using S: analysis of time-to-event data. CRC press", I have found the definition of the empirical survivor function (esf) is S(t) = (number of individuals > t)/n . But from page 80, chapter 3 of...
  16. K

    Tires Probability Question

    Question: You recently bought a new set of four tires from a manufacturer who just announced a recall because 2% of that particular brand of tires are defective. What is the probability that at least one of your tires is defective? You may assume that the tires are defective independently of...
  17. B

    Combining two sources of uncertainty

    I will use an imperfect dice for simplicity. Let's assume there are two factors that influence the probability of the results obtained from throwing a dice: 1) the way the dice is thrown and 2) imperfections of the dice. Let's assume that we know what is the probability distribution of the...
  18. E

    Probability HW help

    I need help with these problems. I worked them out, got answers, and checked the back of the book to see if I got them correct. A pair of six-sided balanced dice are rolled. What are the probabilities of getting the sum of the face values as follows? (a) 8 (b) 6 or 9 (c) 3, 8, or 12 (d)...
  19. K

    Help with what a question is asking

    I know how to calculate probabilities, but I want to make sure that I am understanding the question. "What is the probability that the Dow Jones Index will increase by more than 11% in the coming year?" and "What is the probability Dow (X) will decrease more than 11% in the coming...
  20. C

    Simple Set THeory/Probability Problem

    Hello all, I'm very new to statistics as well as this forum, so please bear with me. I've tried solving this for about 30 minutes now and I've made pretty much 0 progress on it. The question is: Suppose that evens A and C are mutually exclusive. P(not A)=0.7, P(CB)=0.4, what are the...