1. O

    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...
  2. M

    Statistically Significant Data for Test Engineer

    A common engineering experiment is to test something until failure to determine its ultimate break strength. Sample sizes can range from 5 to 100 pieces. I would like to know what statistical tests are used to make sure the data is good. Statistical tests that I am aware of are used to...
  3. S

    Excel 95 % confidence interval

    Hello everybody, I am learning about data science at the moment. I want to calculate the 95% confidence interval for the amount of Long-Term Debt that I could expect to have with Long Term Assets of $50,000,000. I calculated a regression analysis for the impact of long-term assets on long-term...
  4. A

    Wilcoxon (SL) Regression - Confidence Intervals on Parameter Estimators?

    Does anyone know of a method to create confidence intervals on the SLR parameter estimates of a Wilcoxon Regression model?
  5. Blueray123

    Confidence level?

    A poll of 80,000 like minded people is taken. The sample is 400. It is a yes or no poll. The results are 395 Yes and 5 No. What can be deduced from this poll? Would this poll be valid to the total voting citizens of the US? Lets just say 275 million people.
  6. J

    Confidence interval of density distribution

    Hi, I am a university student and I have a trouble with the following example. This is not what I am actually confronting, but I think it will make you understand my point easily. What I want to know is the true distribution of the hair length of a man. So I randomly chose 10 men, and I took...
  7. C

    Trying to calculate confidence intervals

    Hi everyone. The numbers below are the annual maintenance costs of a program I am working on. I'd like to use the data set to estimate future costs at different confidence intervals (e.g. 80%). Can you help me with what distribution would be best and how to produce a CDF that I can graph...
  8. R

    Optimizing Burn-in Testing

    I'm new to the field and have a problem that I'm currently stuck on. For burn-in testing of a machine, we cycle test it 500 times. Sometimes it'll fail before that point, get repaired, and then continue testing. Sometimes it won't fail by the conclusion of the test. The question I've been tasked...
  9. K

    Confidence interval of mean of queue length (M/M/1)

    Goodday, For a simulation course I had to simulate a single server queue with Poisson processes for arrival and departure (M/M/1). Now, this really was not the issue, the issue is where I personally want to add a kind of validity check, which naturally can only be done with statistics. I...
  10. J

    Basic Sample Sizing Question

    Hi all, I haven't done any stats for a long time, I am looking to incorporate some stats into my Ops Risk role to get a little edge. I think I am on the right track with this first little attempt but just wanted to run it by the forum for any feedback. So at work, we are starting a new...
  11. S

    Confidence of Distribution

    Hi all, say I have a known normal distribution, which was created by an experiment. Now, I take another measurement, one only, and assume this is the mean of my new distribution, with similar properties as the known distribution. How can I calculate, how sure I am that this new distribution...
  12. I

    Computing confidence for multivariant tests

    We'd like to compute an overall confidence value for a test with multiple variants (sometimes with no control). We've used Student's and Welch's T-Test for A/B tests in the past, but these multi-way tests don't seem to fit the bill. What sort of formula should we be using to compute...
  13. E

    Calculate Probability of a value greater than knowing the Mean, St Deviation...?

    I need to Calculate the probability of get 20000 or more with the following statistics; Statistics: Forecast values Trials 5,000 Base Case 0.00 Mean 14,755.75 Median 10,993.67 Mode --- Standard Deviation 10,519.67 Variance 110,663,505.00 Skewness 1.45 Kurtosis 4.40 Coeff. of...
  14. L

    iPhone sensor data mining to predict events

    I'm working on a concept for a mobile device programming class. I have no clue whether or not it will work. Basically my plan is to mine all of the sensor data I can (magnetometer, gyroscope, noise level, etc) during different types of events. These might things like walking, at work, driving to...
  15. J

    Determine if a worker differs from typical performance?

    I'll start with some details about my specific situation. I've got a database that contains records of jobs, clients, and workers. My goal is to see if a given worker has a lower than average score when it comes to converting first-time jobs into recurring jobs. I do this by taking all...
  16. Lukan27

    Interpretting Levene's test (Stata)

    I looked this up quite a bit, and found alot about it, but I'm still not entirely sure if I got it right. I just recently got an assignment back with some needed corrections; this one is about Levene's test and t-test. My lecturer wants me to do a Levene's test (robvar in Stata), and I get these...
  17. S

    On constructing 95% confidence ellipses for bivariate data in SAS - help!!

    Hi guys! I would very much like to plot / sketch / graph a 95% confidence ellipse using base SAS for a small data set I have, of size 9. I'm unsure of how to proceed. This is the two methods I tried to use without much success: proc princomp DATA=scores OUT=scores1 COVARIANCE...
  18. A

    one-sided confidence intervals

    [b]1. Let X1,...,Xn be iid with cdf Fθ, where Fθ(x) = (x/θ)^β for x in [0, θ]. Here β>0 is a known constant and θ>0 is an unknown parameter. Let X(n)= max (X1,...,Xn). f(x|θ)=nβ(x^(nβ-1))/(θ^(nβ)) when x is in [0, θ]. Part one was to show that P= X(n)/θ is a pivot for θ. Which I did by...