All posts by Jimmy F

(Machine) Learning About Love: Who will Leave The Bachelor next?

What is love?  Can you define love, or do you merely recognize its presence or absence without binding it in a definition?  A computer may be able to provide a definition of love, regurgitated from a database, but can a computer recognize love?  If defining love is so difficult for us, many of whom might cop out with “I know it when I see it”, how much more difficult will a computer find this challenge?  On a lark, I decided to implement a machine learning system to predict a few things about a television show about love, ABC’s “The Bachelor”.

My girlfriend fiancée regularly watches The Bachelor; valuing our relationship, I am sometimes drawn in.  The premise of the show is this: Chris Soules (The Bachelor), a single man, acts as the sole decision maker in a competition among 30 eligible women to identify his potential bride.  Each week, one or more of the 30 women is eliminated as the bachelor gets to know them.  This is the 19th Season of this show (there have been 10 iterations of its partner show, “The Bachelorette”)

If we can teach a computer to recognize some measure of love, it is certainly possible to predict who will depart the show next.  Regardless of how we frame this question, there are challenges.  First off, we have no clue how the Chris Soules “mental machine” works.  More importantly, the 30 data points we have (one per contestant) contain far too many features (most of which aren’t quantifiable) of which we only know a dozen or so.  Given a dozen features, we cannot build a statistically reliable model for prediction.  For the sake of entertainment and self-enrichment, I decided to make an attempt in the face of these challenges.

Machine Learning Techniques

I decided to utilize a Decision Tree such that I could investigate the factors personally, but I decided to expand and also utilize a Support Vector Machine as well.  An understanding of the SVM coupled with a quick glance at the Scikit-Learn algorithm cheat-sheet drove my decision to incorporate both.

Data Collection

I first wrote a scraper to pull some data off the open Internet about each candidate; a photograph, age, some ancillary data provided.  From the photograph, I manually identified features such as ethnicity as well as hair types (length, curliness, color).  From the ancillary data, I acquired other quantifiable numbers: number of tattoos and age as well as whether or not that contestant had been eliminated.

Each individual is encoded in JSON like so:

 {
     "hair_wavy": "straight",
     "hometown_name": "Hamilton",
     "height_inches": 64,
     "age": 24,
     "num_tattoos": 0,
     "hair_color": "dark",
     "name": "Alissa Giambrone",
     "hair_length": "chest",
     "date_fear": " Running into recent exes",
     "occupation": "Flight Attendant",
     "likes": [
        "Family",
        "friends",
        "laughter",
        "hope",
        "faith"
     ],
     "free_text": " If I never had to upset others, I would be very happy.  If I never got to play with puppies, I would be very sad.  If you could be any animal, what would you be? A wild mustang. Free to run and explore, they're unpredictable and beautiful, and are loyal to their herd.  If you won the lottery, what would you do with your winnings? Adopt dogs and charter a jet for my friends anf fmaily to fly around Europe, with unlimited champagne and a hot air balloon ride over Greece.  What's your most embarrassing moment? I was in-depth stalking a guy's Facebook page and sent my friend a long, detailed text about my findings...except I sent it to him. Oops.  What is your greatest achievement to date? Getting my yoga certification because I've been able to inspire others to do yoga and become instructors!  ",
     "eliminated": true,
     "photo_url": "http://static.east.abc.go.com/service/image/ratio/id/90fe9103-e788-418d-9eb1-4204b7ba1b96/dim/690.1x1.jpg?cb=51351345661",
     "hometown_state": " NJ",
     "ethnicity": "caucasian",
     "goneweek": 2,
     "featured": true,
     "featured_num": 6,
     "intro_order": 21
}

Some data properties are categorical (such as ethnicity and hair color); some data properties are ordinal (hair length), and some data properties are ratios (such as age or number of tattoos). The Python script encodes categorical data into ordinal, numeric values through a lookup dictionary.

hair_length = dict({"neck": 1,
                    "shoulder": 2,
                    "chest": 3,
                    "stomach": 4})

Workflow

Given this sparse data, it’s hard to train the machine.  More importantly, we can’t break the data into training and testing data; because there’s so little data, we need to use all of it.  For this reason, I decide to randomly pick 25% of the data for training the tree or SVM, then run these very same points through the classifier.  To offset this horrible violation of machine learning principals, I’ll run the model a thousand times and see who gets mis-classified as “eliminated” the most.

Here’s some code I wrote to train the samples:

def week_predict(tgt_data, elims, tgt_week, sc_learn):
    """
    Given some data, make some predictions and return the average accuracy.
    :param tgt_data: json structure of data to be formatted
    :param elims: eliminated
    :param tgt_week:
    :param sc_learn:
    :return:
    """

    learn_values = data_formatter(tgt_data, elims, tgt_week)
    x = list()
    y = list()
    samples = set()
    while len(samples) < (len(learn_values) * 0.25):
        samples.add(random.randint(0, len(learn_values) - 1))
    learn_arr = learn_values.values()
    # print "Sample selection: ", samples
    for index in samples:
        x.append(learn_arr[index][0])
        y.append(learn_arr[index][1])

    # These next two lines courtesy of:
    # http://scikit-learn.org/stable/modules/tree.html
    clf = sc_learn
    try:
        clf = clf.fit(x, y)
    except ValueError:
        # Sometimes we try to train with 0 classes.
        return dict({"accuracy": 0, "departures": []})
    c = 0
    departures = list()
    for item in learn_values:
        if clf.predict(learn_values[item][0]) != learn_values[item][1]:
            c += 1
            if learn_values[item][1] == 0:  # if they aren't eliminated
                departures.append(item)
    accuracy = round((len(learn_values) - c) / float(len(learn_values)) * 100, 2)
    ret_val = dict({"accuracy": accuracy,
                    "departures": departures})
    return ret_val

Output

These are my leading predictors for departure.  For the decision tree, here we have it:

Departing: Britt Nilsson votes: 640
Departing: Carly Waddell votes: 581
Departing: Jade Roper votes: 538
Departing: Becca Tilley votes: 520
Departing: Megan Bell votes: 506
Departing: Kaitlyn Bristowe votes: 365

For the SVM, the output:

Departing: Britt Nilsson votes: 749
Departing: Megan Bell votes: 722
Departing: Becca Tilley votes: 714
Departing: Jade Roper votes: 707
Departing: Carly Waddell votes: 629
Departing: Kaitlyn Bristowe votes: 619

I’ve arranged each of these in descending order; the more votes someone has for departure, the more frequently they are miscategorized as eliminated based on who has already been eliminated and who is still there.

Analysis

Does this make sense given the current state of the contest? After discussing these predicted outcomes with expert viewers, they were adamant that Britt, the contestant I’ve pegged as being most likely to leave, has almost no chance of departing.  She made a strong impression on Chris and seems to have a strong connection with him, so for her to leave would be a shocker; on the other hand, many of these same viewers thought Kaitlyn had a good chance of winning, which would validate her low departure score.

UPDATE: 

This blog post didn’t make it to the Internet in time for these predictions to be evaluated in public.  As such, (spoiler alert) we know that Britt and Carly departed in Week 7, followed by Jade in Week 8.  As such, I will make some predictions for next week:

Decision Tree results:

Departing: Becca Tilley: 3590
Departing: Whitney Bischoff: 3357
Departing: Kaitlyn Bristowe: 3320

Support Vector Machine results:

Departing: Becca Tilley: 1799
Departing: Whitney Bischoff: 1760
Departing: Kaitlyn Bristowe: 1715

Analysis 2.0

We’ve trained an SVM with just a few variables that don’t capture the essence of the problem very well.  Furthermore, we did no fine tuning for the parameters in the SVM, nor did we prune the decision tree.

In order to rectify the data issue, I have put out a call to fans of The Bachelor for additional data about any facet of the show, including:

  • How many kisses per episode per contestant
  • Who gets what date?
  • Number of minutes of on-air time featured per episode, per contestant
  • Distance from contestant hometown to Arlington, Iowa
  • Any other data

Tools Used

I used mostly stock Python libraries to gather data and produce these predictions; for web scraping, I used selenium and BeautifulSoup.  For machine learning, scikit-learn.  For keeping the code clean, pylint.

Code is available at: https://github.com/jamesfe/bachelor_tree

If you have questions, feel free to tweet me them over to @jimmysthoughts!

Beer Caps to Coffee Tables

Some years ago, I lived in Norfolk, VA with a friend who loved craft beer as much as I did. Our hoppy passion motivated us to brew beer at home, visit local craft beer stores, and generally enjoy our nights with a brew here or there. Subconsciously knowing it would be a brilliant idea, we used a tupperware box next to our refrigerator to house a growing collection of beer caps, feeding it a single cap as each beer departed the cold, destined for enjoyment.

After a few years, I realized the box was close to being filled to the brim. The mechanical gears in my head were cranking out an idea to do something creative with the bottle caps. I wanted to incorporate some things I’d learned in my classes related to imaging, computer vision, data mining, and spectral signatures. I also had an old square coffee table (36″x36″) that could be the canvas to this project. This was the beginning of a fun exploration in image processing with python to create a bottle cap magnum opus.

Getting it Done
There were a few things I needed to do; first, I needed more caps.  Given the size of a bottle cap (1″) minus some width for a border around the table and a little space between the caps, I found that the table would accept a 30 cap by 30 cap grid, therefore I needed at least 900 caps.  A local bar supported this effort by hosting a 5 gallon bucket for the bartender to drop caps into in lieu of the trash can.

Second, I needed a way to extract the data (color; specifically red, green, and blue) from each individual cap.  I originally arranged the images on a gridded sheet of paper, took a photo, and extracted them row-by-column after performing some image transforms to account for the skewed nature of the image.  As it turns out, there is no good way to get a completely top-down image of the caps; it will always turn out to be smaller at the top and larger at the bottom depending on the angle you held the camera at. The data wasn’t fantastic and as more caps came in, I knew I needed a better way; a quick survey of computer vision capabilities turned up a concept called a Hough Transform.

Hough transforms are a method of identifying shapes that can be approximated by equations in images; in this case, a circle with a roughly known radius was the target. This synopsis is a vast simplification, but for each pixel in the output image (of the same size as the input image), the algorithm polls those surrounding pixels that might form a circle and assigns a value to that pixel. Based on all the pixels in the image, one can then surmise that the pixels with values above a certain threshold are the center point for a circle of known radius. To facilitate the discovery of circles of a specific radius (as many caps have concentric circle patterns), I used a Sobel operator to convert the image into an edge-only image.

caps_on_sheet
A subset of the caps, spread out and photographed.

Although I initially wrote my own Sobel Filter and Hough Transform in Python, I think it’s smarter to use OpenCV, which I later discovered.  OpenCV is a set of computer vision related functions written in C/C++ with wrappers for Python; Hough transforms are only one of the things that OpenCV can simplify from a multi-hour debacle into a few minutes of digging in the documentation for the right tool. Here  is a quick snippet of something that took me dozens of lines of code in earlier editions:

def cv2hough(sobel_image, color_image, minrad, maxrad):
    '''
    Identifies and cuts out to a directory potentially circular
    shapes that match a known radius range.
    :param sobel_image: sobel-filtered image
    :param color_image: non-sobel filtered version of colored_image
    :return:
    '''
    in_cv_image = cv2.imread(sobel_image, 0)
    avg_rad = (minrad+maxrad)/2
    circles = cv2.HoughCircles(in_cv_image, cv.CV_HOUGH_GRADIENT, 1, 65,
    param1=90, param2=15,
    minRadius=minrad, maxRadius=maxrad)
    exportCircles(circles, color_image, 'caps', avg_rad)

(Documentation for cv2.HoughCircles)

This code snippet concludes by sending a list of all the places on the image where it thinks a cap might be to “exportCircles”, where those caps are then cut out of the image and sent to a 30px x 30px JPG file.

circle_3_img
A cap, post-extraction. It’s a rough approximation, but the hough transform was sufficient.

Once we have a directory containing hundreds and hundreds of caps, we can begin some analysis. (Full disclosure: I manually scrolled through the images and deleted those that appeared unusable.) Python was used to calculate statistics for each bottle cap image, and eventually stored the data in a structure. Each pixel is calculated applying a red (R), green (G), and blue (B) value. We can average these and get average (R,G,B) triplets for each bottle cap, that is to say; a cap is “mostly” red, or “mostly” blue, etc. I soon found that these numbers weren’t that descriptive and began to work in the Hue, Saturation, and Value color spaces. (HSL & HSV: Wikipedia).

Protip: I used a quick one-liner to convert from RGB to HSV before storing the data:
colorsys.rgb_to_hsv(rgb[0], rgb[1], rgb[2])

To save time cataloging 900 bottle caps and associated pixels, I pickle (serialize) each cap as I generate the data on it so I can quickly reference a data structure containing the caps and rearrange them as I see fit.

caps_avg
The caps by average, as the computer sees them.
comp_output
The caps as we see them; the final arrangement was sorted by hue then saturation.

Final Steps: Output
I originally wanted to see what it would look like when I rearranged the bottle caps into different patterns. This is where we do that, and based on the data we have and the framework we’ve built, outputting an image or a HTML document (this is a really hasty solution!) becomes fairly easy, minus one hiccup.

def first_sort(self):
    '''
    Reach into the internal config and find out what we want to have as
    our first order sort on the caps.
    :return:
    '''
    self.sortedDatList = sorted(self.imageDatList,
                                key=lambda thislist: thislist[
                                    self.sorts[self.conf['first_sort']]])
    del self.imageDatList
    self.imageDatList = self.sortedDatList

def second_sort(self):
    '''
    Second sort on the caps: sort rows individually.
    Example: We want a 30x30 grid of caps, sorted first by hue, then by
    saturation.
    We sort by hue in first_sort, then in second_sort, we sort 30 lists
    of 30 caps each individually and replace them into the list.
    :return:
    '''
    ranges = [[self.conf['out_caps_cols'] * (p - 1),
               self.conf['out_caps_cols'] * p] for p in
              range(1, self.conf['out_caps_rows'] + 1)]
    for r in ranges:
        self.imageDatList[r[0]:r[1]] = sorted(self.imageDatList[r[0]:r[1]],
                                              key=lambda thislist: thislist[
                                                  self.sorts[self.conf[
                                                      'second_sort']]])

Here we see two functions: firstSort and secondSort. You can guess that we sort the caps once, then sort them again; what may not be apparent from this code is that the second sort (which is performed on a different attribute), is performed based on the out_caps_rows attribute. This is the hiccup; you must sort multiple sub-segments of the array of bottle caps, in essence, sorting the rows after the columns have been generated. Otherwise each row of bottle caps will have a random pattern as the image trends from one extreme (top) to the other (bottom).

caps_organized
Caps, laid out and ready to be transferred to the table.

The Physical Construction
To finish the project, I physically arranged a pattern based on informal votes from friends and acquaintances. I built a 1/2″ lip around the table with “Quarter-Round” molding. I glued this down, sealed the seams with wood glue, and painted everything black.

I filled the bottom of this open-top area with playground sand. This minimized the volume that I would have to fill in with expensive epoxy resin. It had the secondary benefit of lightening up the entire display, knowing the epoxy would darken it. I ordered two kits of “AeroMarine 300/21 Epoxy Resin” (for a total of 3 Gallons) from the internet. Ultimately, I arranged the caps on a sheet of butcher’s paper and transferred them one-by-one to the sand box.

A few friends, the famous roommate, and I gathered (with beers); we mixed the resin and began the process of pouring the resin onto the table. The one unseen consequence of the sand was that when the epoxy entered the sand, it pushed air upwards, causing the caps to float; we quickly used toothpicks to push the caps down into the sand, then poured more resin over top.

caps_final
The table, post-drying and finished.

Code for this was hacked together over a number of weeks, I’ve consolidated it here: https://github.com/jamesfe/capViz.  Unfortunately, most of this code was written in a disheveled, disconnected manner and I’m just now beginning to tie it together into one well documented, good-practice PEP-8 compliant piece, but feel free to poke around and let me know what you think!

Thanks to The Birch for all the beer caps!

If this interested you, follow me on Twitter! @jimmysthoughts