# Passing Analysis

Passing analysis is one of the
Time Series Analysis
for the changing caused by hours.
For example,
the data of products from the start of use to out of order.
And the data of the change of the body from taking medicines.

In this page, the explanatory variable (X) is the hour.

##
ANOVA and Decision Tree

If data set is made as like "first day, a month, three months",
we can use them as
Category Data
.

By transforming each period into characters like ,
or sampling the time of just "1 day, 2 days, 3 days",
we can use this approach.

Then some category data analysis like
ANOVA
and
decision tree
is useful to compare levels.

These methods answer the question, "Hours are related to the change?"

Some software of
decision tree
changes the data into levels automatically.

##
Regression Analysis

If we need a formulation,
of "increasing" or "curve",
regression analysis
is useful.

When we use regression analysis, X is used as quantity data.

NEXT Trend Analysis for Many Variables