# LCL and UCL of percentages and difference of percentages

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## LCL and UCL of percentages and difference of percentages

 I am trying to help a colleague cobble together a quick lesson for policymakers. 3 questions. 1) how to get CTABLES to show LCL and UCL of percentages 2) Does CTABLES use asymmetric confidence limits. 3) what conceptual takeaways are missing? * CNN data about Moderna Covid Vaccine copied down during broadcast. * find 95% confidence interval of difference of proportions when proportions are extreme. * including zero hits on one DV. * note the disciplinary difference in term 'cases'. * note this an actual control grouping not just comparison grouping. * further considerations at * "https://www.bbc.com/news/health-54902908". * "https://www.cnn.com/2020/11/16/health/moderna-vaccine-results-coronavirus/index.html". * The DV is a dichotomy a special instance of the level of measurement. * Since there is only 1 possible interval, all intervals are identical. * There are many ways to look at such data. data list list /Group (f1)GroupSize(f5) Positive (f2) Severe(f2). BEGIN DATA 1 15000 90 11 2 15000 5   0 END DATA. VARIABLE LABELS Group 'Treatment group' GroupSize '# participants' Positive '# hits - individuals with positive tests' Severe '# hits  - individuals with severe symptoms'. Value labels Group 1 'Placebo Control' 2 'Actual vaccine treatment'. WEIGHT BY GroupSize. * Custom Tables. CTABLES   /VLABELS VARIABLES=Group Positive DISPLAY=NAME   /TABLE Group [COUNT F40.0 COLPCT.COUNT PCT40.1 COLPCT.COUNT.LCL PCT40.1 COLPCT.COUNT.UCL PCT40.1]   BY Positive   /CATEGORIES VARIABLES=Group ORDER=A KEY=VALUE EMPTY=INCLUDE   /CATEGORIES VARIABLES=Positive ORDER=A KEY=VALUE EMPTY=EXCLUDE   /CRITERIA CILEVEL=95   /COMPARETEST TYPE=PROP ALPHA=0.05 ADJUST=BONFERRONI ORIGIN=COLUMN INCLUDEMRSETS=YES     CATEGORIES=ALLVISIBLE MERGE=YES STYLE=APA SHOWSIG=NO. * Are differences in treatment vs control results readily attributable to chance? * How precise is the estimate of effectiveness? Is the uncertainty due to imprecision large enough to effect planning?   ----- Art Kendall Social Research Consultants -- Sent from: http://spssx-discussion.1045642.n5.nabble.com/===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD Art Kendall Social Research Consultants
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## Re: LCL and UCL of percentages and difference of percentages

 COLPCT.COUNT.LCL  COLPCT.COUNT.UCL Yes, these are asymmetrical:Lower bound ( pi ) = IDF.BETA(α/ 2 ,^w'i +.5 , W '−w'i +.5 ),Upper bound ( pi ) = IDF.BETA(1− α / 2 ,w'i +.5 , W'−w'i +.5)See Algorithms doc for unmangled formulaOn Mon, Nov 16, 2020 at 8:28 AM Art Kendall <[hidden email]> wrote:I am trying to help a colleague cobble together a quick lesson for policymakers. 3 questions. 1) how to get CTABLES to show LCL and UCL of percentages 2) Does CTABLES use asymmetric confidence limits. 3) what conceptual takeaways are missing? * CNN data about Moderna Covid Vaccine copied down during broadcast. * find 95% confidence interval of difference of proportions when proportions are extreme. * including zero hits on one DV. * note the disciplinary difference in term 'cases'. * note this an actual control grouping not just comparison grouping. * further considerations at * "https://www.bbc.com/news/health-54902908". * "https://www.cnn.com/2020/11/16/health/moderna-vaccine-results-coronavirus/index.html". * The DV is a dichotomy a special instance of the level of measurement. * Since there is only 1 possible interval, all intervals are identical. * There are many ways to look at such data. data list list /Group (f1)GroupSize(f5) Positive (f2) Severe(f2). BEGIN DATA 1 15000 90 11 2 15000 5   0 END DATA. VARIABLE LABELS Group 'Treatment group' GroupSize '# participants' Positive '# hits - individuals with positive tests' Severe '# hits  - individuals with severe symptoms'. Value labels Group 1 'Placebo Control' 2 'Actual vaccine treatment'. WEIGHT BY GroupSize. * Custom Tables. CTABLES   /VLABELS VARIABLES=Group Positive DISPLAY=NAME   /TABLE Group [COUNT F40.0 COLPCT.COUNT PCT40.1 COLPCT.COUNT.LCL PCT40.1 COLPCT.COUNT.UCL PCT40.1]   BY Positive   /CATEGORIES VARIABLES=Group ORDER=A KEY=VALUE EMPTY=INCLUDE   /CATEGORIES VARIABLES=Positive ORDER=A KEY=VALUE EMPTY=EXCLUDE   /CRITERIA CILEVEL=95   /COMPARETEST TYPE=PROP ALPHA=0.05 ADJUST=BONFERRONI ORIGIN=COLUMN INCLUDEMRSETS=YES     CATEGORIES=ALLVISIBLE MERGE=YES STYLE=APA SHOWSIG=NO. * Are differences in treatment vs control results readily attributable to chance? * How precise is the estimate of effectiveness? Is the uncertainty due to imprecision large enough to effect planning? ----- Art Kendall Social Research Consultants -- Sent from: http://spssx-discussion.1045642.n5.nabble.com/ ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD -- Jon K Peck[hidden email] ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD
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## Re: LCL and UCL of percentages and difference of percentages

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