diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSClusteredZScoreWalker.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSClusteredZScoreWalker.java
index b9da136dc..e858deb12 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSClusteredZScoreWalker.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSClusteredZScoreWalker.java
@@ -20,9 +20,9 @@ import net.sf.samtools.SAMRecord;
  * To change this template use File | Settings | File Templates.
  */
 public class NQSClusteredZScoreWalker extends LocusWalker<LocalMapType, int[][][]> {
-    static final int WIN_SIDE_SIZE = 4;
-    static final int Z_SCORE_MAX = 4;
-    static final int Z_SCORE_MULTIPLIER = 3; // bins are Z_SCORE * (this) rounded to the nearst int
+    static final int WIN_SIDE_SIZE = 5;
+    static final int Z_SCORE_MAX = 7;
+    static final int Z_SCORE_MULTIPLIER = 30; // bins are Z_SCORE * (this) rounded to the nearst int
     static final int MM_OFFSET = 1;
     static final int MATCH_OFFSET = 0;
     static final int MAX_Q_SCORE = 2 + QualityUtils.MAX_REASONABLE_Q_SCORE;
@@ -129,8 +129,8 @@ public class NQSClusteredZScoreWalker extends LocusWalker<LocalMapType, int[][][
     }
 
     public String header() {
-        String format = "%s\t%s\t%s\t%s\t%s%n";
-        return String.format(format, "ZScore", "Expected_Mismatch", "Empirical_Mismatch", "Expected_MM_As_Q", "Empirical_MM_As_Q");
+        String format = "%s\t%s\t%s\t%s\t%s\t%s%n";
+        return String.format(format, "ZScore", "N_obs", "Expected_Mismatch", "Empirical_Mismatch", "Expected_MM_As_Q", "Empirical_MM_As_Q");
     }
 
     public String formatData ( int[][] matchMismatchQ, int zScoreBin ) {
@@ -142,18 +142,18 @@ public class NQSClusteredZScoreWalker extends LocusWalker<LocalMapType, int[][][
         for ( int i = 0; i < MAX_Q_SCORE; i ++ ) {
             match += matchMismatchQ[i][MATCH_OFFSET];
             mismatch += matchMismatchQ[i][MM_OFFSET];
-            expMMR += QualityUtils.qualToProb(i)*matchMismatchQ[i][MATCH_OFFSET];
-            expMMR += QualityUtils.qualToProb(i)*matchMismatchQ[i][MM_OFFSET];
+            expMMR += QualityUtils.qualToErrorProb((byte)i)*matchMismatchQ[i][MATCH_OFFSET];
+            expMMR += QualityUtils.qualToErrorProb((byte)i)*matchMismatchQ[i][MM_OFFSET];
         }
         
         expMMR = (expMMR / ( match + mismatch ));
         double empMMR = ((double) mismatch)/(match + mismatch);
-        int expMMRAsQ = QualityUtils.probToQual(expMMR);
-        int empMMRAsQ = QualityUtils.probToQual(empMMR);
+        int expMMRAsQ = QualityUtils.probToQual(1-expMMR);
+        int empMMRAsQ = QualityUtils.probToQual(1-empMMR);
 
-        String format = "%f\t%f\t%f\t%d\t%d%n";
+        String format = "%f\t%d\t%f\t%f\t%d\t%d%n";
         
-        return String.format(format, zScore, expMMR, empMMR, expMMRAsQ, empMMRAsQ);
+        return String.format(format, zScore, match+mismatch, expMMR, empMMR, expMMRAsQ, empMMRAsQ);
     }
 
 }
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSCovariantByCountsWalker.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSCovariantByCountsWalker.java
index 664b10789..170665660 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSCovariantByCountsWalker.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSCovariantByCountsWalker.java
@@ -126,15 +126,15 @@ public class NQSCovariantByCountsWalker extends LocusWalker< LocalMapType, int[]
         for ( int i = 0; i < MAX_Q_SCORE; i ++ ) {
             match += qScores[i][MATCH_OFFSET];
             mismatch += qScores[i][MM_OFFSET];
-            expErr += QualityUtils.qualToProb(i)*qScores[i][MATCH_OFFSET];
-            expErr += QualityUtils.qualToProb(i)*qScores[i][MM_OFFSET];
+            expErr += QualityUtils.qualToErrorProb((byte)i)*qScores[i][MATCH_OFFSET];
+            expErr += QualityUtils.qualToErrorProb((byte)i)*qScores[i][MM_OFFSET];
         }
 
         expErr = expErr/(match + mismatch);
-        int expAsQ = QualityUtils.probToQual(expErr);
+        int expAsQ = QualityUtils.probToQual(1-expErr);
 
         double empErr = ((double)mismatch)/(match+mismatch);
-        int empAsQ = QualityUtils.probToQual(empErr);
+        int empAsQ = QualityUtils.probToQual(1-empErr);
 
         return String.format(DATA_FORMAT, smDev, lgDev, match, mismatch, expErr, empErr, expAsQ, empAsQ);
     }
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSExtendedGroupsCovariantWalker.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSExtendedGroupsCovariantWalker.java
index 5e4c2db41..c5a6236a7 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSExtendedGroupsCovariantWalker.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSExtendedGroupsCovariantWalker.java
@@ -26,7 +26,7 @@ public class NQSExtendedGroupsCovariantWalker extends LocusWalker<LocalMapType,
     final int MAX_QSCORE = QualityUtils.MAX_REASONABLE_Q_SCORE+1;
     int NQS_GROUPS;
 
-    public static final String DATA_FORMAT = "%d\t%d\t%d\t%d\t%f%n";
+    public static final String DATA_FORMAT = "%d\t%d\t%d\t%d\t%d%n";
     public static final String TEXT_FORMAT = "%s\t%s\t%s\t%s\t%s%n";
 
 
@@ -143,7 +143,7 @@ public class NQSExtendedGroupsCovariantWalker extends LocusWalker<LocalMapType,
     }
 
     public String createHeader() {
-        return String.format(TEXT_FORMAT, "Qscore_Reported", "NQS_Group", "Mismatches", "Total", "Mismatch_Rate");
+        return String.format(TEXT_FORMAT, "Qscore_Reported", "NQS_Group", "Mismatches", "Total", "Empirical_Qscore");
     }
 
     public String formatNQSMismatchCountString(int qscore, int group, long[][][] cumulativeBins) {
@@ -151,6 +151,6 @@ public class NQSExtendedGroupsCovariantWalker extends LocusWalker<LocalMapType,
         long ct = cumulativeBins[group][COUNT_OFFSET][qscore];
         double mmr = (ct > 0) ? mm/ct : -1;
 
-        return String.format(DATA_FORMAT, qscore, group, mm, ct, mmr);
+        return String.format(DATA_FORMAT, qscore, group, mm, ct, QualityUtils.probToQual(1-mmr));
     }
 }
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSTabularDistributionWalker.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSTabularDistributionWalker.java
index dee2231f0..08bffb501 100644
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSTabularDistributionWalker.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NQSTabularDistributionWalker.java
@@ -87,6 +87,7 @@ public class NQSTabularDistributionWalker extends LocusWalker<LocalMapType, NQSD
 
 class NQSDistributionTable {
 
+    
     public final int MM_OFFSET = 0;
     public final int MATCH_OFFSET = 1;
 
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/poolseq/PowerAndCoverageWalker.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/poolseq/PowerAndCoverageWalker.java
index d03ec1982..efdf27ce7 100644
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/poolseq/PowerAndCoverageWalker.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/poolseq/PowerAndCoverageWalker.java
@@ -51,12 +51,19 @@ public class PowerAndCoverageWalker extends LocusWalker<SQuad<Integer>, SQuad<Lo
     @Argument(fullName="poolSize", shortName="ps", doc="Number of individuals in the pool", required = true)
     public int numIndividuals = 0;
 
+    @Argument(fullName="alleleFrequency", shortName="af", doc="Calculate power for this many alleles in the pool", required=false)
+    public int alleleFreq = 1;
+
     protected PrintStream outputWriter = null;
 
     public void initialize() {
         if(numIndividuals <= 0) {
             throw new StingException("Pool size must be greater than 1. You input "+numIndividuals);
         }
+
+        if ( alleleFreq > 2*numIndividuals ) {
+            throw new StingException("Allele frequency must be less than the number of alleles in the pool");
+        }
         if( outputFile != null ) {
             try {
                 outputWriter = new PrintStream(outputFile);
@@ -255,7 +262,7 @@ public class PowerAndCoverageWalker extends LocusWalker<SQuad<Integer>, SQuad<Lo
     }
 
     private double getSNPProportion() {
-        return 1/(2.0*numIndividuals);
+        return alleleFreq/(2.0*numIndividuals);
     }
 
 }