Creating the great business leaders

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o

Regression (Linear, Logistic)

o

Time Series Forecasting

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Creating the great business leaders

Linear regression

is an approach for modeling the relationship between a scalar

dependent variable

y

and

one or more

explanatory variables

(or independent variables) denoted

X

. The case of one explanatory

variable is called

simple linear regression

. For more than one explanatory variable, the process is

called

multiple linear regression

.

[1]

_{(This term should be distinguished from}

_{multivariate linear regression}

_,

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

In a cause and effect relationship, the independent

variable is the cause, and the dependent variable is

the effect. Least squares linear regression is a method

for predicting the value of a dependent variable

Y

_,

based on the value of an independent variable

X

.



Linear regression is a way to model the relationship

between two variables. But be warned, just because

two variables are related, it does not mean that

one

causes

_{the other.}

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Creating the great business leaders

Logistic regression

, or

logit regression

, or

logit model

[1]

_{is a}

_regression

_{model where the}

_{dependent variable}

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1.

Data Preparation

2.

Identify Attribute and Label

3.

Calculate each X

2

, Y

2

, XY and Sum Total

4.

Calculate a and b based on given formula

5.

Construct Linear Regression Model

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Y = a + bX

where:

Y = Dependent Variable

X = Independent Variable

a = constant

b = regression coefficient(skew);

a = (

Σy) (Σx²) –

(

Σx

) (

Σxy

)

n(Σx²) –

(

Σx

)²

b = n(

Σxy

)

–

(

Σx

) (

Σy

)

n(Σx²) –

(

Σx

)²

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

Calculate Regression Coefficient (a)

a = (

Σy) (Σx²) –

(

Σx

) (

Σxy

)

n(Σx²) –

(

Σx

)²

a = (72) (4876)

–

(220) (1640)

10 (4876)

–

(220)²

a = -27,02



Calculate Regression Coefficient(b)

b = n(

Σxy

)

–

(

Σx

) (

Σy

)

n(Σx²) –

(

Σx

)²

b = 10 (1640)

–

(220) (72)

10 (4876)

–

(220)²

b = 1,56

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Creating the great business leaders

Y = a + bX

Y = -27,02 + 1,56X

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1.

Prediksikan Jumlah Cacat Produksi jika suhu dalam keadaan tinggi

(Variabel X), contohnya: 30°C

Y = -27,02 + 1,56X

Y = -27,02 + 1,56(30)

= 19,78

2.

Jika Cacat Produksi (Variabel Y) yang ditargetkan hanya boleh 5 unit,

maka berapakah suhu ruangan yang diperlukan untuk mencapai target

tersebut?

5 = -27,02 + 1,56X

1,56X = 5+27,02

X = 32,02/1,56

X = 20,52

Jadi

Prediksi Suhu Ruangan

yang paling sesuai untuk mencapai target

Cacat Produksi adalah sekitar

20,52

0

C

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Creating the great business leaders



Sarah, the regional sales manager is back for more help



Business is booming, her sales team is signing up thousands of new clients, and she

wants to be sure the company will be able to meet this new level of demand, she now

is hoping we can help her do some prediction as well



She knows that there is some correlation between the attributes in her data set (things

like temperature, insulation, and occupant ages), and she’s now wondering if she can

use the previous data set to predict heating oil usage for new customers



You see, these new customers haven’t begun consuming heating oil yet, there are a lot

of them (42,650 to be exact), and she wants to know how much oil she needs to expect

to keep in stock

in order to meet these new customers’ demand



Can she use data mining to examine household attributes and known past consumption

quantities to anticipate and meet her new customers’ needs?

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

Sarah’s new data mining objective is pretty clear:

she wants to

anticipate demand for a consumable product



We will use a linear regression model to help her with her desired

predictions



She has data,

1,218 observations

that give an attribute profile for

each home, along

with those homes’ annual heating oil

consumption



She wants to use this data set as training data to predict the usage

that

42,650 new clients will bring to her company



She knows that these new

clients’ homes are similar in nature to her

existing client base, so the existing customers’

usage behavior

should serve as a solid gauge for predicting future usage by new

customers.

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Creating the great business leaders

We create a data set comprised of the following attributes:



Insulation

: This is a density rating, ranging from one to ten, indicating the

thickness of each

home’s insulation

. A home with a density rating of one

is poorly insulated, while a home with a density of ten has excellent

insulation



Temperature

: This is the average

outdoor ambient temperature

at each

home for the most recent year, measure in degree Fahrenheit



Heating_Oil

: This is the

total number of units of heating oil

purchased by

the owner of each home in the most recent year



Num_Occupants

: This is the total

number of occupants living

in each

home



Avg_Age

: This is the average age of those occupants



Home_Size

: This is a rating, on a scale of one to eight, of the home’s

overall size. The higher the number, the larger the home

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

Ask Dataset to the Assistant

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Creating the great business leaders

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

Time series forecasting is one of the

oldest known predictive analytics

techniques



It has existed and been in

widespread use even before

the

term “predictive analytics”

was ever coined



Independent or predictor variables are

not strictly necessary for

univariate time series forecasting

, but are strongly recommended for

multivariate time series



Time series forecasting

methods:

1.

Data Driven Method

: There is

no difference between a predictor and a target

.

Techniques such as time series averaging or smoothing are considered data-driven

approaches to time series forecasting

2.

Model Driven Method

: Similar

to “conventional” predictive models, which have

independent and dependent variables, but with a twist:

the independent variable is

now time

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Creating the great business leaders



There is

no difference between a predictor and a target



The predictor is also the target variable



Data Driven Methods:



Naïve Forecast



Simple Average



Moving Average



Weighted Moving Average



Exponential Smoothing



Holt’s

Two-Parameter Exponential Smoothing

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

In model-driven methods,

time is the predictor

or independent

variable and

the time series value is the dependent variable



Model-based methods are generally preferable when the time series

appears to have a

“global”

pattern



The idea is that the model parameters will be able to capture these

patterns



Thus enable us to make predictions for any step ahead in the future under the

assumption that this pattern is going to repeat



For a time series with local patterns instead of a global pattern,

using the model-driven approach requires specifying how and when

the patterns change, which is difficult

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Creating the great business leaders



Linear Regression



Polynomial Regression



Linear Regression with Seasonality



Autoregression Models and ARIMA

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

RapidMiner’s

approach to time series is based on

two main data

transformation

processes



The first is windowing to transform the time series data into a

generic data set: this step will convert the last row of a window

within the time series into a label or target variable



We

apply any of the “learners” or algorithms to predict the target

variable and thus predict the next time step in the series

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Creating the great business leaders



The parameters of the Windowing operator allow changing the size of the

windows, the overlap between consecutive windows (also known as step size),

and the prediction horizon, which is used for forecasting



The prediction horizon controls which row in the raw data series ends up as the

label variable in the transformed series

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Creating the great business leaders



Window size

: Determines how many “attributes” are created for

the

cross-sectional data



Each row of the original time series within the window width will become a

new attribute



We choose

w = 6



Step size

: Determines how to advance the window



Let us use

s = 1



Horizon

: Determines how far out to make the forecast



If the window size is 6 and the horizon is 1, then the seventh row of the original

time series

becomes the fist sample for the “

label

”

variable



Let us use

h = 1

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