
5 Data Analysis
Summarizing Data
In this section.. .
“Overview” on page 5-10
“Measures of L ocation” on page 5-10
“Measures of Scale” on page 5-11
“Shape of a Distribution” on page 5-11
Overview
MATLAB includes many functions for summarizing the overall location, scale,
and shape of a data sample.
One of the advantages of working in MATLAB is that functions operate on
entire arrays of data, not just on single scalar values. The functions are said
to be vectorized. Vectorization allo ws for both efficient problem formulation,
using array-based data, and efficient computation, using vectorized statistical
functions.
Note This section continues the data analysis f rom “Preprocessing Data”
on page 5-3.
Measures of Location
Summarize the location of a data sample by finding a “typical” value. Common
measures of location or “central tendency” are computed by the MATLAB
functions
mean, median,andmode:
x1 = mean(count)
x1 =
32.0000 46.5417 65.583 3
x2 = median(count)
x2 =
23.5000 36.0000 39.000 0
5-10
Comentários a estes Manuais