How to count number of Numeric values in a column

Question

I have a dataframe, and I want to produce a table of summary statistics including number of valid numeric values, mean and sd by group for each of three columns. I can\'t seem

Answer 1

These are a few add-on packages that might help (see Quick-R)

Using the Hmisc package

library(Hmisc)

describe(mydata) 
# n, nmiss, unique, mean, 5,10,25,50,75,90,95th percentiles 
# 5 lowest and 5 highest scores

Using the pastecs package

library(pastecs)

stat.desc(mydata) 
# nbr.val, nbr.null, nbr.na, min max, range, sum, 
# median, mean, SE.mean, CI.mean, var, std.dev, coef.var 

Using the psych package

library(psych)
describe(mydata)
# item name ,item number, nvalid, mean, sd, 
# median, mad, min, max, skew, kurtosis, se

I'd use describe.by from the psych package;

> describe.by(biastable, as.factor(Nominal))
group: 1
         var n mean   sd median trimmed  mad  min  max range  skew kurtosis   se
Nominal    1 9 1.00 0.00   1.00    1.00 0.00 1.00 1.00  0.00   NaN      NaN 0.00
Actual     2 8 0.12 0.01   0.12    0.12 0.01 0.11 0.13  0.03  0.09    -1.47 0.00
LinPred    3 8 0.99 0.08   0.98    0.99 0.10 0.89 1.09  0.20  0.04    -1.70 0.03
QuadPred   4 8 0.99 0.08   0.99    0.99 0.10 0.88 1.09  0.20 -0.04    -1.64 0.03
------------------------------------------------------------------------ 
group: 3
         var n mean   sd median trimmed  mad  min  max range skew kurtosis   se
Nominal    1 9 3.00 0.00   3.00    3.00 0.00 3.00 3.00  0.00  NaN      NaN 0.00
Actual     2 9 0.37 0.03   0.36    0.37 0.03 0.32 0.42  0.10 0.15    -1.50 0.01
LinPred    3 9 3.12 0.24   3.05    3.12 0.30 2.79 3.50  0.71 0.15    -1.52 0.08
QuadPred   4 9 3.10 0.23   3.06    3.10 0.34 2.79 3.46  0.67 0.12    -1.51 0.08
------------------------------------------------------------------------ 
group: 6
         var n mean   sd median trimmed  mad  min  max range skew kurtosis   se
Nominal    1 9 6.00 0.00   6.00    6.00 0.00 6.00 6.00  0.00  NaN      NaN 0.00
Actual     2 9 0.71 0.04   0.70    0.71 0.04 0.66 0.78  0.12 0.46    -1.30 0.01
LinPred    3 9 6.02 0.30   5.91    6.02 0.28 5.61 6.47  0.86 0.28    -1.43 0.10
QuadPred   4 9 5.99 0.31   5.93    5.99 0.25 5.55 6.49  0.94 0.26    -1.26 0.10
------------------------------------------------------------------------ 
group: 10
         var n  mean   sd median trimmed  mad   min   max range skew kurtosis   se
Nominal    1 9 10.00 0.00  10.00   10.00 0.00 10.00 10.00  0.00  NaN      NaN 0.00
Actual     2 9  1.16 0.07   1.14    1.16 0.09  1.06  1.25  0.19 0.09    -1.71 0.02
LinPred    3 9  9.85 0.60   9.76    9.85 0.74  9.16 10.72  1.56 0.24    -1.76 0.20
QuadPred   4 9  9.79 0.62   9.63    9.79 0.72  9.05 10.78  1.72 0.27    -1.65 0.21
------------------------------------------------------------------------ 
group: 30
         var n  mean   sd median trimmed  mad   min   max range skew kurtosis   se
Nominal    1 9 30.00 0.00  30.00   30.00 0.00 30.00 30.00  0.00  NaN      NaN 0.00
Actual     2 9  3.53 0.22   3.51    3.53 0.21  3.25  3.85  0.60 0.23    -1.58 0.07
LinPred    3 9 30.08 1.55  29.88   30.08 1.44 27.70 32.66  4.96 0.21    -1.27 0.52
QuadPred   4 9 29.92 1.51  30.00   29.92 1.44 27.44 32.38  4.94 0.04    -1.22 0.50
------------------------------------------------------------------------ 
group: 50
         var n  mean   sd median trimmed  mad   min   max range skew kurtosis   se
Nominal    1 9 50.00 0.00  50.00   50.00 0.00 50.00 50.00  0.00  NaN      NaN 0.00
Actual     2 9  5.91 0.51   5.82    5.91 0.43  5.43  6.94  1.51 0.90    -0.73 0.17
LinPred    3 9 50.40 3.98  48.77   50.40 3.21 44.89 57.37 12.48 0.49    -1.16 1.33
QuadPred   4 9 50.24 3.97  48.91   50.24 2.65 44.49 57.01 12.52 0.39    -1.21 1.32
------------------------------------------------------------------------ 
group: 150
         var n   mean   sd median trimmed   mad    min    max range  skew kurtosis   se
Nominal    1 9 150.00 0.00 150.00  150.00  0.00 150.00 150.00  0.00   NaN      NaN 0.00
Actual     2 6  17.23 0.97  17.20   17.23  0.67  15.90  18.80  2.90  0.25    -1.23 0.39
LinPred    3 6 147.19 8.11 147.01  147.19 11.13 138.04 155.39 17.36 -0.01    -2.22 3.31
QuadPred   4 6 147.77 7.95 147.48  147.77 10.95 139.60 157.78 18.17  0.07    -2.10 3.25
------------------------------------------------------------------------ 
group: 250
         var n   mean    sd median trimmed  mad    min    max range skew kurtosis   se
Nominal    1 9 250.00  0.00 250.00  250.00 0.00 250.00 250.00  0.00  NaN      NaN 0.00
Actual     2 9  28.83  1.18  28.70   28.83 0.89  27.10  31.20  4.10 0.59    -0.57 0.39
LinPred    3 9 246.29 10.57 245.98  246.29 9.31 231.46 264.81 33.35 0.33    -1.26 3.52
QuadPred   4 9 251.51  8.84 248.45  251.51 5.08 240.41 268.30 27.89 0.62    -1.04 2.95
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