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Annotated Output | Frequencies

Computer Output

The frequency distribution provides the baseline information.

> FrequencyTable <- table(Outcome)
> FrequencyTable
Outcome
0 3 4 5 7 9 
2 1 2 1 1 1 
> prop.table(FrequencyTable)
Outcome
    0     3     4     5     7     9 
0.250 0.125 0.250 0.125 0.125 0.125

In each case, the table header row lists all the actual scores in the entire data set.

“FrequencyTable” indicates the number of times that score exists. For example, the score of 4 was listed 2 times.

“PropTable” provides the proportion of cases for each possible score. For example, of the 8 scores in the entire data set, the score of 4 was listed 2 times and 2/8 is .250.

The table of percentiles shows the key elements to be interpreted.

> length(Outcome)
[1] 8
> summary(Outcome)
   Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
   0.00    2.25    4.00    4.00    5.50    9.00

The score at the 50th percentile is 4. Similarly, a score of 2.25 is at the 25th percentile and a score of 5.50 is at the 75th percentile.

APA Style

Though often not reported, simple summary statistics like the median and quartiles provide the reader with basic frequency information about the variable under investigation.

The participants (N = 8) had a low Mdn Outcome score of 4.00 (IQR = 2.25 – 5.50).