Chapter 2 Descriptives
2.1 Descriptives
An example from Kerlinger (1969, pp. 93-95):
Data |
---|
1 |
2 |
3 |
4 |
5 |
2.1.1 Results Overview
By Hand | JASP | SPSS | SAS | Minitab | R | |
---|---|---|---|---|---|---|
Mean | 3.0 | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 |
Variance | 2.5 | 2.500 | 2.500 | 2.500 | 2.500 | 2.500 |
Median | NA | 3.000 | 3.000 | 3.000 | 3.000 | 3.000 |
Standard Deviation | NA | 1.580 | 1.580 | 1.580 | 1.580 | 1.580 |
SE(Mean) | NA | 0.707 | 0.707 | 0.707 | 0.707 | 0.707 |
2.1.2 By Hand
Calculations by hand can be found in Kerlinger (1969, pp. 93-95).
Result:
Mean = 3
Variance = 2.5
Note: Kerlinger calculated the population variance, however as all statistical software computes the sample variance, the formula was adapted accordingly to be divided by N-1.
2.1.4 SPSS
DATASET ACTIVATE DataSet1.=Data
DESCRIPTIVES VARIABLES/STATISTICS=MEAN STDDEV VARIANCE MIN MAX SEMEAN.
2.1.7 R
mean(desc.data2$Data)
## [1] 3
sd(desc.data2$Data)
## [1] 1.581139
var(desc.data2$Data)
## [1] 2.5
median(desc.data2$Data)
## [1] 3
<- function(x) sqrt(var(x)/length(x))
se se(desc.data2$Data)
## [1] 0.7071068