1. N

    Question Regarding Standard Deviation of Rate Vs. Time

    Hello, I am not particularly well versed in statistics but I am doing some research and encountered something I didn't understand and was hoping someone here could help. For my research, we need to find the pump speed with the most consistency when filling a vial to 50ml. I am not sure if I...
  2. T

    Value of Features and Attributes to Statistically Estimate Rental Unit Pricing

    Let me start by saying I don't have much of a background in statistics, but I am attempting to inject some statistical analysis into a relatively straightforward pricing model that I use to price rental units. I'm just looking for a place to start, so any help would be appreciated. I apologize...
  3. K

    understanding lending rates on lending applications

    Hi there, I was wondering if anyone had experience in modelling lending rates on lending applications? How do you interpret a negative coefficient, i.e. based on visual analysis when rate goes down, applications should naturally go up; however the coefficient is negative. Regards
  4. P

    Confidence intervals for difference between Poisson rates

    Hi, My data consists of occurrences of words in time windows. E.g.: Day; Word; Frequency 1; "dog"; 45 1; "cat"; 2 ... 2; "dog"; 90 2; "cat"; 4 ... I would like to estimate the ratio of day-to-day difference (i.e. for dog: 90-45/45 = 100%). For cat the increase is also 100%, but due to...
  5. S

    Comparing two ratios - Which test should I use?

    It has been years since I attempted statistics and I would appreciate any form of help. I am looking at data, and I want to see if one rate influences another rate. I want to know if two rates are correlated and significance of that correlation. The data looks similar to something like this...
  6. M

    Test the fit of rate data to a Poisson process

    How can you test the whether a collection of rate data is consistent with a Poisson process? I am investigating a random process which conceptually could be a Poisson process. I have a collection of rate data (counts/min), and I would like to test whether their distribution is consistent with...
  7. K

    Rate per 100,000 persons for a quarter - divide annual population by 4?

    Hello, How do I calculate the rate per 100,000 persons of something occurring for a quarter of a year? Specifically, If I have a count of 12 people bought cars in the September quarter and an annual population of 2000 how do I calculate the appropriate rate per 100000? Fo a whole...
  8. B

    Comparing crude rates based on less than 10 events

    I need to compare crude rates between two areas, and have found it can be done as follows: D=r1 -r2 where: r1 = rate for County 1 r2 = rate for County 2 CI = D ± square root of (CL12 + CL22) where: CL1 = confidence limit for County 1 rate CL2 = confidence limit for County 2 rate and CL...
  9. A

    Determining significant (or otherwise) difference between 2 rates of change

    Dear Users, I am trying to determine the statistical significant difference (or otherwise) between 2 series of data and am unsure how to proceed. It is rates of admission for arthritis between 2 countries. Country A the average rate of increase per year is 8.1%, and for Country B the...