# probability

1. ### 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...

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...
3. ### 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...
4. ### Having a girl the same as AT LEAST one girl? CONFUSION!!

It’s a combinatorics project for my beginner stats class. I’ve done the project several times and keep getting it wrong. The question reads: “ Is having a girl the same event as having AT LEAST one girl?” AND then it asks me: “Is it possible to calculate these probabilities?” This project is...
5. ### Expectation with confidence

Hello, It has been a while since I used my probability and statistics. My question is: Say a group of 5 five people need to find the similarities between two foto's individually. After checking the result is that they found 3, 6, 2, 8, 1 correct similarities. How can you say with a certain...
6. ### Developing a 64 Card Poker Deck Variant - Curious About Probabilities

Straight Variant: The only difference is that the top rank can bridge the 1st rank to form a sequence. Think of it as if Q, K, A, 2, 3 was a legal straight. How is that calculated? A More Complex Straight Variant: This one gets trickier, I think. In this variant, there are: 64 cards 4 suits 13...
7. ### Galton Watson branching process

Using Galton Watson branching process. Assume that a fox had 0,1,2,3 offspring with probabilities p0,p1,p2,p3 respectively. find the probability distribution for G1 and G2. below is what I’ve done so far I think this is correct for G1 however I’m unsure where to even start with G2.
8. ### Sensitivity of a diagnostic test

There is an exercise that I am not able to solve: Diagnostic tests A1 and A2 are used to detect the presence or absence of a disease. The results of A1 and A2 are a priori independent of the presence or absence of the disease. A1 and A2 have sensitivity Sen1 and Sen2, respectively. A new...
9. ### Validate my algorithm with probability?

Before I start I wanna say sorry. This post might a bit vague, I'm not really sure where I'm going and it's been a while since I took a stat class. I'm hoping someone can nudge me in the right direction here, kinda lost at the moment. We have an algorithm for correcting people's height - it's...
10. ### Probability given an occurrence rate (small airplane fatal accidents)

Hi All, I would like to know if the method I’m using to calculate a probability based on an occurrence rate is correct or if there is a better method to use. Here is some context to give you an idea of what I’m working with: I am looking at determining the probability of a fatal accident...
11. ### Sports outcome probability

Hello! Here is the scenario I have: In ice hockey, team A is ahead at the end of the 2nd period (they have games of 3 periods for those who do not know). When team A is ahead at this point in the game, they go on to win 75% of the time. When team B is losing at the end of the 2nd period, as they...
12. ### Multi-roll, 12 sided die outcomes (used brute force 725,000 die rolls)

I have forgotten my grad school probability and need some help with the following. I am trying to create a .xls that I can use to look at the odds of multiple dice throws. Quantity of dice = 10 (n) # of sides per dice = 20 (s) Each dice has the following colors instead of numbers: 4 Yellow...
13. ### How do you put a Distribution in a Risk Analysis?

In conducting a Probability Risk Analysis or statistical risk Analysis, for example over the actions of nature for a particular period of time and for a particular geographical location, one is expected to put a distribution over all the actions of nature and choose the action that maximizes...
14. ### Probability Over 2 Sequences Of Trials

Hey everyone! I'm coding a program that identifies appearances of a lowercase "x" in a base64 encoded string. Like the following: DWADCrxV+PhR4zxkQrIMUtarkN11aitHI8DEnzyG19CD... I know the probability of finding at least one "x" in a sequence of 10 chars. My doubt is about dealing with...
15. ### Probability of Vehicles and Pedestrians meeting

Hi, I need to produce a probability for a vehicle and a pedestrian meeting along a 1km road. Here is what I know: •1km road •cars take 3 minutes to travel •pedestrians take 12 minutes to travel •30 cars an hour •20 pedestrians an hour The cars and pedestrians may also be grouped or evening...
16. ### Quality Control/Probability Problem

A production engineer has designed a system to remove sugars from a liquid product. Each product must contain an amount of sugar less than or equal to 12g. The engineer randomly samples 3 products and finds the sugar contents to be 4.5, 3.7, and 3.2g respectively. The sample mean is 3.8g and the...

19. ### Card picking dependant probability without replacement - P(6,6,Red)

Hi All, I'm trying to teach myself statistics online @ khan academy and although its a wonderful resource I have no one to turn to for help when I don't understand. I hope someone here might be able to give me some advice. I've made some questions up myself to try and work out the answer and...
20. ### Leave-one-out error strictly decreasing when number of parameters is increased, when it should not be?

People may or may not be able to help intuitively shed light on my problem. Maybe I haven't considered some aspects. I'm running a non-parametric (kernel) regularized least squares estimation on some binary training data to then predict probabilistic values for the non-training data. I have 9...