Sridhar

Hi Erik,
     Tahnks for the reply. I did try this method, but  the problem is most of the cells i got or less thank 5 and i dont know what to do. Can you suggest what to od if i have celss less than 5.
      Another question is because i am having all the combinations can i apply ANOVA(DOE) to fine out which plot and which grade gives me…[Read more]

Hi,
       I dont think you have to wait for 220 tasks, because any way you are converting them into defects per million opportunities. If it is 220 or less it doesn’t matters, the final metric you are going to say is defects per million opportunities.
sridhar
 

Hi chandra,
    Send me your mail id.
sridhar
 

Hi,
     This 3.4 comes from the normal distribution curve. You check a stad normal distribution curve at 4.5 sigma value. Multiply the area outside this curve by one million you get 3.4. You may ask why we take 4.5 instead sigma.
    Then 1.5 sigma assumed as long term shift. That is the process may shift 1.5 std deviations in the long term. T…[Read more]

Hi,
      Probably you did n’t get the right concept of six sigma. Six sigam implies that you are able to incorporate 6 std deviations in between your target (center) to the closet specification limit. Now when you say 5 sigma implies you are able keep 5 stad deviations in between your target and closest specification. This implies that your std…[Read more]

Hi,
       I think i will go with the Erick. For this kind of data it is better to do the contingency table approach. I am not sure whether i understand your question correct or not. I am trying to explain what i understood.
the resutls are 
                                Large deals                small deals     …[Read more]

Hi,
     It is very simple but the only disadvantage is you know when you have around 10 things to prioritize you cant compare all the 10 at a time. Thats what we can avoid with avoid. It compares only pair wise and later on you can even check whether any bias is there in this scores. If so do it again until no bias. Yes it also have some dis…[Read more]

Hi Antony,
       can you send me your mail id, i will send you one paper and an excel sheet to do prioritization using AHP.
sridhar
 

Hi,
          You have to take a transformations on the response data if it is of attribute type, depending on the distribution. May be in your case it may follows poission distribution. Take a transformation do the similar analysis as you will for continuous response.
      You can look into minitab for this. Are you can go through this…[Read more]

Hi,
        Try with AHP ( Analytic Hierarcy process ).
sridhar
 

Hi,
      Sample size calculation depends on the following factor.
1. Your confidence level
2. Margin of error
3. Std deviation of population ( in case of proportions it is sqrt(p*q)
     Once you assumed these values calcualte the sample size as
          n = Z^2 * std deviation / (error)^2
    The final decision on sample size depens o…[Read more]

Hi,One way of prioritizing is AHP (Analytic Hierarcy Process). The concept is comparing at a time only two characterstics i.e. pair wise comparision. All the pair combinations are compared and given a score on a scale of 1 to 9. Once all the combinations are over then we standardize the scores get the most important ones. One more advantage of…[Read more]

Hi,
        I think the simplest way of looking for outlier is Box-Plots. The points which are falling outside the whiskers of box plot are called as outliers.
hope this helps you
sridhar
 

Hi,
       This is just the manipualation of the formulas. I will prove the calculations.
      Cpk = min { USL-Average/ 3*sigma , Average – LSL / 3*sigma}
        Cp= (USL – LSL)/6*sigma
        sigma = (USL-LSL)/6*Cp
         Putting sigma in Cpk equation
Cpk=2*Cp/(USL-LSL)*min{USL-Average, Average-LSL}
     = 2*Cp/(USL-L…[Read more]

Hi,
       Box cox method is used to make the non normal data to norma.
You can go through this handbook
      http://www.itl.nist.gov/div898/handbook
this gives you some information about the box cox method. After that you can use any statistical pakcage like MINI TAB etc which will do the transformation.
thanks
sridhar
 

Hi,
    Why dont you try for some transformations like Box – Cox. Generally this transformation makes the data closely to normal. Then you calculate your control limits and convert back to your original values.
sridhar
 

Hi,
       The simple formula to calculate the sample size is
     n = Z^2 * p*(1-p)/(error)^2     for infinite or very large population
    If you have a finite population make the correction as below
        Sample size(for finite population ) = 1/{(1/n) + (1/N)}
        n= same as calculated by the above formula
          N = Populat…[Read more]

Hi,
       You can try QFD(quality function deployment), FMEA(failure mode effect and analysis).You can even try TRIZ(Theory of  Inventive problem solving). Now in new terms even you can think of Desing for six sigma (DFSS). 
sridhar

Hi,
       Always use Cpk for six sigma calculation. When your process is at target then both Your Cp and Cpk are same. Cpk is always less than or equal to Cp. Use Cpk for six sigma calculation.
thanks
sridhar
 

Hi,
         Send me your e – mail i will send you two papers.
 
bye
sridhar