1. B

    'not randomly generated' what does the even mean?!?

    As expressed in this question: The telephone numbers for a region of a state have an area code of 570. The next seven digits represent the local telephone numbers for that region. A local telephone number cannot begin with a 0 or 1. Your cousin lives within the given area code. What is the...
  2. T

    Research design for overlap probability

    I'd like some feedback on both the method and code I'm using to analyze a case study of a person who uses an herbal supplement to help with depression. I will happily take feedback on either the general approach or specifics on the code itself. I really like this forum and am eager for feedback...
  3. D


    Producing machine provides 20% incorrect products. Let's randomly pick 4 produced products. Find the probability that: a) There is exactly one incorrect product. b) There is no incorrect products. c) There is at least one correct product.
  4. S

    Intrabatch variabilty estimated from pooled SD and confidence intervals

    I would like to calculate intrabatch variability of parameter A, which is normally distributed. I have data of 50 batches (the same process), for each batch I have one representative sample with sample size = 10. I have calculated pooled SD from the samples of all 50 batches (I assume this is...
  5. R

    Probability in a card game

    I play a card game called 'Yu-GiOh!'. For those who don't know how this game works, that will be separate paragraphs at the bottom of the page. I have a deck, and I'm looking for the chances of getting a specific one of these using only the starting hand. The numbers are below, (a) and (b) etc...
  6. K

    How can I solve this probability?

    Factory gets supplies delivered every day from the producers. The probabilities of supplies arriving successfully on a given day are 0.97 for the first supplier; 0.87 for the second supplier and 0.75 for the third supplier. The factory requires deliveries from at least one producer to keep up...
  7. K

    how can I solve this lottery probability?

    Lottery consists of 50 tickets, amongst them five tickets with a prize of €10, three tickets with a prize of €5. The rest are empty. What is the probability of buying three lottery tickets and all having prizes?
  8. K

    Probability limit of ridge estimator mu hat

    I have been working on the following question for a while but I stucked at a certain point. I have done part a and b and I found = (I_T + D'D)y where I_T is the identity matrix with dimension T, lambda is tuning parameter and D is the second order difference matrix which is a tridiagonal and...
  9. S

    R and Stats: Multiple t-testing

    So 60 labs decided to group up to test the null hypothesis (sample mean is equal to zero) against the alternative (sample mean is not). The 60 labs collect 10 samples each and all use an α = 0.05 level. Assuming the null hypothesis is true: a) Probability that no labs reject the null? b)...
  10. A

    Need to understand equation

    Hi All I am reading some research paper on machine learning and come across below paragraph, can someone help me decode these two equations mentioned below. New to statistics and probability so apologies in advance if my question is very basic. Here is an example showing the problem with...
  11. S

    Please tell if this is correct

    There are error in programs which have two parts Part A and Part B. P(error in A) = 0.13 P(error in B) = 0.38 P(program crash when error in A) = 0.6 P(program crash when error in B) = 0.692 P(prog crash when an error in both A and B) = 0.79 Q1)Your program crashed. Find P(error in both...
  12. A

    How can I make a range (0, 1) for related dataset/objects/rows

    I have some data containing 6 different types of values. They are, ID means the main ID sub_ID means the subsection/part of the ID orig_content means the amount in milligram (mg) they have originally stored in this ID, orig_min means the minimum amount in milligram (mg) they can store in this...
  13. S

    Is my approach correct for this binomial distribution question?

    Here is the question: So it would be: n = 5, p = 9/15 = 0.6 , q= 1-0.6 =0.4 P(x=3) = (5C3) * 0.6^3 *(0.4)^(5-3) = 0.3456 P(x=4) = (5C4) * 0.6^4 *(0.4)^(5-4) = 0.2592 P(x=5) = (5C5) * 0.6^5 *(0.4)^(5-5) = 0.07776 So adding the 3 prob = 0.68256 Ans. We will not...
  14. S

    Is P(x) = P(x | y )*P(y) + P(x | ~y )*P(~y) according to Bayes theorem?

    Can anyone tell me if this equation valid? If yes how? I have tried to check on google but couldn't find it! If this equation is valid then I will be able to solve a question on Bayes theorem. Thanks!
  15. S

    Finding Variance in Poisson distribution question

    Hello! Can anyone tell me how to solve this question? Consider that X~ Poisson(μ) and P(X > 0) = e ^−1.5 Find the variance? I need P(x =0) to use the formulae of Poisson distribution. But I don't have that!
  16. I

    probability task

    I started my studies in statistics and was given an exercise, which I have a problem with: On average, one woman in 70 is pregnant. A pregnancy test has been developed. However, the test sometimes gives false results, i.e. it detects a true pregnancy in 97 out of 100, and in the absence of...
  17. B

    Probability of choosing 4 sick people from 100 where there is a probability of 8.6% for each of them to have a disease.

    I have the following task: There is 4% of sick people in a population. There is 5% chance for a positive test for a healthy person. There is 2% chance for a negative test for a a sick person. We tested 100 people and 4 had a positive test. What is the probability of such an outcome? So far I...
  18. C

    A statistical test to determine strength of correlation (or probability of certain outputs) over three timepoints

    Hello, New to this forum and bit of a stats newbie so forgive me for any if my question is too vague or I say anything incorrect. My dataset is ELISA outputs for 10 individuals over three timepoints with sample size. I want to see if the individuals remain in the same order over the 3...
  19. A

    statistics for engineers question please help

    I need to write an original question. I will use your answer as a guide to write an original question by myself. I couldn't find a guide or some examples from books or videos. I would reallly appreciate if you know and let me know where I can also find some examples . I dont know where or how...
  20. M

    Conditional probability

    Hi! I'm working on a binomial conditional probability question and I am stuck. I would really appreciate some help. The question is as follows: You have a box of n=40 bolts. The probability of a bolt being faulty is p=0.005. You are told that at least one of the bolts is faulty, and asked: What...