1. bukharin

    What are the odds?

    Spotted in a Lancet article from 2011: I was curious to see how they got such an extraordinary odds ratio and confidence interval. In the article, under "Statistical analysis" [sic] it says "Microsoft Excel was used for all analyses" but doesn't explain the odds ratio. Disappointing. (The...
  2. O

    Binomial - probability from average result?

    I'm looking at recovery rates for stolen cars. Across the whole State there were 15,000 cars stolen, of which 62% were recovered. I now want to see if any particular sub-regions are significantly different to the State. Can I use 0.62 as the binomial probability for a car being recovered...
  3. T

    Need Help in STAT Project

    Please help me I have this project for Stat in Excel. I need to answer the following questions in the the attached worksheet. I have completed questions 1 - 4, But I am having hard time figuring out question 5 - 9. Please help me I am desperate. thank you. The College Gift Shop wants to have...
  4. C

    Determining the winner between two pricing strategies

    I'd like to conduct an A/B split test of pricing strategies on two web pages, and I'd like to know when to stop the test and declare the leader as the winner, at a specified level of confidence. The winner is the offer that returns the most revenue per visitor. Example: Offer A gets 1000...
  5. D

    [Excel] - Help for Large Dataset

    I have a large data set (30 columns, tons of rows). I want to calculate the correlation between each of the 30 columns. The problem is that for any given at most 8 o the columns are populated. So correl() by itself would not work. I tried setting up an array formula to calculate the...
  6. B

    Script Help Or Excel Add-in

    Note: please see my next post to get a better understanding of what I am looking for. Thanks -Ben Hello, I have been using R/S+ for years and love the software. Still a novice but I can do what i need to. Anyway, I am working on a forecasting project and would like to create a script that...
  7. A

    Is a Chi Square an appropriate test for this situation?

    Hello : ) I've been struggling for a while with this now; any help will be very much appreciated. I'm working on a project, which in part looks at whether the same whales are seen together more often than would be expected by random chance. Looking through my text book I thought the Chi...
  8. K

    Help - comparing percentages in programmatic survey data

    I am a public health researcher that usually does qualitative research and am now trying to analyze a quantitative survey (in Excel no less). Can anyone help me figure out how to compare two percentages from my results to see if they are statistically significant? A bit of background, I...
  9. G

    Deciles and zero values

    Please excuse what may be a simple question, but i am not a big stats person. I'm calculating the decile breaks for a large set of data, 74k records. It's population data for US census tracts. I'm using excel's percentile.inc formula, so in other words, =PERCENTILE.INC(C$2:C$74134,0.1), etc...
  10. M

    ANOVA? PLEASE HELP :) im so confused

    Hello :wave: , I think of ANOVA analysis as being useful when we want to see if there is a significant difference between the means of levels. Particularly with the one-way-ANOVA, there is one categorical vaiable ... with a few levels .... and one continuous, with a mean number for each...
  11. A

    Correlation Analysis Against Artificial / Ranked Factor(s)

    Guys, I have an interesting situation here and a few questions related. Let me sketch it out. SITUATION: Someone conducted a correlation analysis and they claim correlation exists, they found it, it's strong/valid, they separated correctly based on found factors. Overall, the point of...
  12. S

    Write Array to Excel in R

    How do I write an array to .xlsx file. I want to do it in a loop and would like to write it in same sheet.
  13. N

    How to rank (overall) correlation of variables within a correlation matrix

    Hello, I have six correlation matrices in an Excel spreadsheet. Each has the same variables but reports on a different group. I would like to rank the variables across all groups from least correlated to most correlated. There are 8 variables: ENNMN.r CONTAG.r LSI.r ED.r PAFRAC.r...
  14. W

    correlation question/help

    Hi I am working with some data from excel with about 400 data points. I ran a correlation and found out that .90324 is correlated. However, my question is, Is it possible to find out what the .10 data that is not correlated is . Thanks
  15. J

    Importing Excel matrix to R.

    For an easy example, assume that Excel data ""text.xls"" in Excel 2003 (old version) version 1 3 2 5 located at the root directory c:\\ . If we want to import the matrix to an R data matrix with same size in R data directory, I used the command read.csv(file="c:\\test. xls"...
  16. S

    Find standard error from mean and upper/lower quartile?

    Hi folks, I'm hoping there's a straightforward answer to this (that isn't "no") :tup: For some data I know the mean, the upper and lower quartile figure, and also the number of observations on which it is based. I would like to know the standard error. Is there a way of working this...
  17. J

    Exponential Distribution

    ok so my problem is: An outbreak of a particular type of timber infestation occurs, on average, every 30 years for a given region. assuming the probability of an infestation follows an exponential probability distribution, what is the probability of two infestation occurring within 6 years...
  18. T

    Normal Probability Distribution

    In 2010, the population of SAT scores were normally distributed with a mean of 1020 (reading and math only) and a standard deviation of 200. The NCAA requires Division I athletes to score at least 820 to compete the first year. A random sample of 4 students is gathered. What is the probability...
  19. T

    Poisson Distribution

    What is the probability there are at least 24 accidents at the intersection in a year if the mean number of accidents per month is 2.2? (answer=0.693) I keep getting 0.706, which is close to the listed answer, but I'm not sure if it is correct. My attempt: P(X≥24) = P(X>24)+P(X=24) =...