Index: trunk/psModules/src/detrend/pmFringeStats.c
===================================================================
--- trunk/psModules/src/detrend/pmFringeStats.c	(revision 23826)
+++ trunk/psModules/src/detrend/pmFringeStats.c	(revision 23989)
@@ -882,5 +882,8 @@
 
     psStats *stats = psStatsAlloc(PS_STAT_SAMPLE_MEDIAN | PS_STAT_SAMPLE_QUARTILE); // Statistics
-    psVectorStats(stats, diffs, NULL, mask, 1);
+    if (!psVectorStats(stats, diffs, NULL, mask, 1)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return 0;
+    }
     float middle = stats->sampleMedian; // The middle of the distribution
     float thresh = rej * 0.74 * (stats->sampleUQ - stats->sampleLQ); // The rejection threshold
@@ -969,9 +972,15 @@
 
     // Get rid of the extreme outliers by assuming most of the points are somewhat clustered
-    psVectorStats(median, science->f, NULL, NULL, 0);
+    if (!psVectorStats(median, science->f, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return NULL;
+    }
     scale->coeff->data.F32[0] = median->sampleMedian;
     for (int i = 0; i < fringes->n; i++) {
         pmFringeStats *fringe = fringes->data[i]; // The fringe of interest
-        psVectorStats(median, fringe->f, NULL, NULL, 0);
+        if (!psVectorStats(median, fringe->f, NULL, NULL, 0)) {
+	    psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	    return NULL;
+	}
         scale->coeff->data.F32[0] -= median->sampleMedian;
         scale->coeff->data.F32[i] = 0.0;
Index: trunk/psModules/src/detrend/pmOverscan.c
===================================================================
--- trunk/psModules/src/detrend/pmOverscan.c	(revision 23826)
+++ trunk/psModules/src/detrend/pmOverscan.c	(revision 23989)
@@ -74,5 +74,8 @@
             mask->data.PS_TYPE_VECTOR_MASK_DATA[i] = 0;
             ordinate->data.F32[i] = 2.0*(float)i/(float)pixels->n - 1.0; // Scale to [-1,1]
-            psVectorStats(myStats, values, NULL, NULL, 0);
+            if (!psVectorStats(myStats, values, NULL, NULL, 0)) {
+		psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+		return false;
+	    }
             reduced->data.F32[i] = psStatsGetValue(myStats, statistic);
         } else if (overscanOpts->fitType == PM_FIT_NONE) {
@@ -275,5 +278,8 @@
 	psFree(iter);
 
-	(void)psVectorStats(stats, pixels, NULL, NULL, 0);
+	if (!psVectorStats(stats, pixels, NULL, NULL, 0)) {
+	    psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	    return false;
+	}
 	psFree(pixels);
 	double reduced = psStatsGetValue(stats, statistic); // Result of statistics
@@ -349,5 +355,8 @@
 	  psString comment = NULL;    // Comment to add
 	  psStats *vectorStats = psStatsAlloc (PS_STAT_SAMPLE_MEAN | PS_STAT_SAMPLE_STDEV);
-	  psVectorStats (vectorStats, reduced, NULL, NULL, 0);
+	  if (!psVectorStats (vectorStats, reduced, NULL, NULL, 0)) {
+	      psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	      return false;
+	  }
 	  psStringAppend(&comment, "Mean Overscan value: %f", vectorStats->sampleMean);
 	  psMetadataAddStr(hdu->header, PS_LIST_TAIL, "HISTORY", PS_META_DUPLICATE_OK, comment, "");
@@ -412,5 +421,8 @@
 	  psString comment = NULL;    // Comment to add
 	  psStats *vectorStats = psStatsAlloc (PS_STAT_SAMPLE_MEAN | PS_STAT_SAMPLE_STDEV);
-	  psVectorStats (vectorStats, reduced, NULL, NULL, 0);
+	  if (!psVectorStats (vectorStats, reduced, NULL, NULL, 0)) {
+	      psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	      return false;
+	  }
 	  psStringAppend(&comment, "Mean Overscan value: %f", vectorStats->sampleMean);
 	  psMetadataAddStr(hdu->header, PS_LIST_TAIL, "HISTORY", PS_META_DUPLICATE_OK, comment, "");
Index: trunk/psModules/src/detrend/pmRemnance.c
===================================================================
--- trunk/psModules/src/detrend/pmRemnance.c	(revision 23826)
+++ trunk/psModules/src/detrend/pmRemnance.c	(revision 23989)
@@ -66,6 +66,8 @@
             values->n = numValues;
             if (!psVectorStats(stats, values, NULL, NULL, 0)) {
-                // Can't do anything about it
-                psErrorClear();
+		psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+		return false;
+	    }
+	    if (isnan(stats->sampleMedian)) {
                 maxMask = max;
                 continue;
Index: trunk/psModules/src/detrend/pmShutterCorrection.c
===================================================================
--- trunk/psModules/src/detrend/pmShutterCorrection.c	(revision 23826)
+++ trunk/psModules/src/detrend/pmShutterCorrection.c	(revision 23989)
@@ -350,10 +350,17 @@
     psStats *rawStats = psStatsAlloc (PS_STAT_SAMPLE_MEDIAN | PS_STAT_SAMPLE_STDEV);
     psStats *resStats = psStatsAlloc (PS_STAT_SAMPLE_MEDIAN | PS_STAT_SAMPLE_STDEV);
-    psVectorStats (rawStats, counts, NULL, NULL, 0);
-    psVectorStats (resStats, resid, NULL, NULL, 0);
+    if (!psVectorStats (rawStats, counts, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return NULL;
+    }
+    if (!psVectorStats (resStats, resid, NULL, NULL, 0)) {
+	psError(PS_ERR_UNKNOWN, false, "failure to measure stats");
+	return NULL;
+    }
 
     // XXX temporary hard-wired minimum stdev improvement factor
     psTrace("psModules.detrend", 3, "raw scatter %f vs res scatter %f\n", rawStats->sampleStdev, resStats->sampleStdev);
     if (rawStats->sampleStdev / resStats->sampleStdev < 1.5) corr->valid = false;
+    if (isnan(rawStats->sampleStdev) || isnan(resStats->sampleStdev)) corr->valid = false;
 
     psFree (rawStats);