Fire up graphlab create


In [1]:
import graphlab
import numpy as np

Load some house sales data


In [2]:
sales = graphlab.SFrame('home_data.gl/')


[INFO] graphlab.cython.cy_server: GraphLab Create v2.1 started. Logging: C:\Users\Matheus\AppData\Local\Temp\graphlab_server_1506298119.log.0
This non-commercial license of GraphLab Create for academic use is assigned to ms.asilvas1@gmail.com and will expire on September 01, 2018.

In [3]:
sales


Out[3]:
id date price bedrooms bathrooms sqft_living sqft_lot floors waterfront
7129300520 2014-10-13 00:00:00+00:00 221900 3 1 1180 5650 1 0
6414100192 2014-12-09 00:00:00+00:00 538000 3 2.25 2570 7242 2 0
5631500400 2015-02-25 00:00:00+00:00 180000 2 1 770 10000 1 0
2487200875 2014-12-09 00:00:00+00:00 604000 4 3 1960 5000 1 0
1954400510 2015-02-18 00:00:00+00:00 510000 3 2 1680 8080 1 0
7237550310 2014-05-12 00:00:00+00:00 1225000 4 4.5 5420 101930 1 0
1321400060 2014-06-27 00:00:00+00:00 257500 3 2.25 1715 6819 2 0
2008000270 2015-01-15 00:00:00+00:00 291850 3 1.5 1060 9711 1 0
2414600126 2015-04-15 00:00:00+00:00 229500 3 1 1780 7470 1 0
3793500160 2015-03-12 00:00:00+00:00 323000 3 2.5 1890 6560 2 0
view condition grade sqft_above sqft_basement yr_built yr_renovated zipcode lat
0 3 7 1180 0 1955 0 98178 47.51123398
0 3 7 2170 400 1951 1991 98125 47.72102274
0 3 6 770 0 1933 0 98028 47.73792661
0 5 7 1050 910 1965 0 98136 47.52082
0 3 8 1680 0 1987 0 98074 47.61681228
0 3 11 3890 1530 2001 0 98053 47.65611835
0 3 7 1715 0 1995 0 98003 47.30972002
0 3 7 1060 0 1963 0 98198 47.40949984
0 3 7 1050 730 1960 0 98146 47.51229381
0 3 7 1890 0 2003 0 98038 47.36840673
long sqft_living15 sqft_lot15
-122.25677536 1340.0 5650.0
-122.3188624 1690.0 7639.0
-122.23319601 2720.0 8062.0
-122.39318505 1360.0 5000.0
-122.04490059 1800.0 7503.0
-122.00528655 4760.0 101930.0
-122.32704857 2238.0 6819.0
-122.31457273 1650.0 9711.0
-122.33659507 1780.0 8113.0
-122.0308176 2390.0 7570.0
[21613 rows x 21 columns]
Note: Only the head of the SFrame is printed.
You can use print_rows(num_rows=m, num_columns=n) to print more rows and columns.

Exploring the data for housing sales


In [4]:
graphlab.canvas.set_target("ipynb")
sales.show(view="Scatter Plot",x='sqft_living',y='price')


Creating a simple regression model of sqft_living to price


In [5]:
train_data,test_data = sales.random_split(.8,seed=0)

Build the regression model


In [6]:
sqft_model = graphlab.linear_regression.create(train_data, target='price',features=["sqft_living"])


PROGRESS: Creating a validation set from 5 percent of training data. This may take a while.
          You can set ``validation_set=None`` to disable validation tracking.

Linear regression:
--------------------------------------------------------
Number of examples          : 16502
Number of features          : 1
Number of unpacked features : 1
Number of coefficients    : 2
Starting Newton Method
--------------------------------------------------------
+-----------+----------+--------------+--------------------+----------------------+---------------+-----------------+
| Iteration | Passes   | Elapsed Time | Training-max_error | Validation-max_error | Training-rmse | Validation-rmse |
+-----------+----------+--------------+--------------------+----------------------+---------------+-----------------+
| 1         | 2        | 1.022825     | 4353807.975556     | 2272374.113520       | 261766.829871 | 284095.366091   |
+-----------+----------+--------------+--------------------+----------------------+---------------+-----------------+
SUCCESS: Optimal solution found.

Evaluate the simple model


In [7]:
print (test_data['price'].mean())


543054.042563

In [ ]:
print (sqft_model.evaluate(test_data))


{'max_error': 4147104.6089961585, 'rmse': 255198.9260303043}

Showing predictions


In [ ]:
import matplotlib.pyplot as plt
%matplotlib inline

In [ ]:
plt.plot(test_data['sqft_living'],test_data['price'],'.',
        test_data['sqft_living'],sqft_model.predict(test_data),'-')

In [ ]:
sqft_model.get('coefficients')

Explore other features in the data


In [ ]:
myfeatures = ['bedrooms', 'bathrooms', 'sqft_living', 'sqft_lot', 'floors', 'zipcode']

In [ ]:
sales[myfeatures].show()

In [ ]:
sales.show(view='BoxWhisker Plot', x='zipcode',y='price')

Build a regression model with more features


In [ ]:
my_features_model = graphlab.linear_regression.create(train_data, target='price', features=myfeatures)

In [ ]:
print(myfeatures)

In [ ]:
print(sqft_model.evaluate(test_data))
print(my_features_model.evaluate(test_data))

Apply learned models to predict prices of 3 houses


In [ ]:
house1 = sales[sales['id']=='5309101200']

In [ ]:
house1


In [ ]:
print(house1['price'])

In [ ]:
print(sqft_model.predict(house1))

In [ ]:
print(my_features_model.predict(house1))

Prediction for a second, fancier house


In [ ]:
house2 = sales[sales['id']=='1925069082']

In [ ]:
house2


In [ ]:
print(house2['price'])
print(sqft_model.predict(house2))
print(my_features_model.predict(house2))

Assignment Task

  • Select the houses inside the zipcode that cointains the highest average house sale price

In [ ]:
highest_price=sales[sales['zipcode']=='98039']
highest_price.head()

In [ ]:
np.average(highest_price['price'])

In [ ]:
sqft_filter = sales[(sales['sqft_living']>2000) & (sales['sqft_living']<4000)]

In [ ]:
float(sqft_filter.num_rows()) / float(sales.num_rows())

In [ ]:
advanced_features = [
'bedrooms', 'bathrooms', 'sqft_living', 'sqft_lot', 'floors', 'zipcode',
'condition', # condition of house       
'grade', # measure of quality of construction       
'waterfront', # waterfront property       
'view', # type of view        
'sqft_above', # square feet above ground        
'sqft_basement', # square feet in basement        
'yr_built', # the year built        
'yr_renovated', # the year renovated        
'lat', 'long', # the lat-long of the parcel       
'sqft_living15', # average sq.ft. of 15 nearest neighbors         
'sqft_lot15', # average lot size of 15 nearest neighbors 
]

In [ ]:
print(sqft_model.evaluate(test_data))

In [ ]:
sqft_model=graphlab.linear_regression.create(train_data,target='price',features=myfeatures)
advanced_model=graphlab.linear_regression.create(train_data, target='price', features=advanced_features)

In [ ]:
print(sqft_model.evaluate(test_data))
print(advanced_model.evaluate(test_data))

In [ ]:
plt.plot(test_data['sqft_living'],test_data['price'],'.',
        test_data['sqft_living'],sqft_model.predict(test_data),'-')

In [ ]:
plt.plot(test_data['sqft_living'],test_data['price'],'.',
        test_data['sqft_living'],advanced_model.predict(test_data),'-')

In [ ]:
#Finished Week 2