Page 22 - Quantitative Data Analysis
P. 22
Quantitative Data Analysis
Simply Explained Using SPSS
that are equal distance from one another. Arithmetic can be
applied; add, subtract, average
a. No “meaningful” zero.
6. Examples:
a. IQ scores (Quasi-interval)
b. Temperature (Fahrenheit and Celsius)
c. F does not mean there is no temperature outside.
If temperature in February is 14 C and temperature
in June is 28 then it is incorrect to say that June has
as twice temperature as February.
d. Percentiles
th
The difference in achievement between the 50
st
and 51 percentiles is not necessarily the same as
th
the difference in achievement between the 90 and
st
91 percentile.
e. Scores on standardized tests
Scores on the GRE Math range from 130 to 170;
zero is not on the scale of possible scores.
7. Ratio Scale
A ratio variable has equal intervals between values and a
meaningful zero point.
8. Examples:
1. Height, weight, time, scores on school tests, dollar bills
2. Number of students in class, number of houses in a city
3. Yearly income, etc.
The Theory and Applications of Statistical Inferences 6
