L21: Privacy

Je↵ M. Phillips

April 6, 2020

Ethics = Empathy

what if you were the date point ?

*¥÷÷ ..

In early 20005,

- I of new tach companies

- eagerness ,interact scientists

Place data set online,

-anongmi?

- state goal- have competition to solve

↳ model, predictions .

Example: Heath Records

Story Time:

I In 2000, Massachusetts released all State employee’s medical

records in an e↵ort for researchers to be able to study them.

I They wiped all ids, but kept zip codes, birthday, gender. Was

declared anonymized by the government.

I In Massachusetts, it was possible to buy voter data for $20. It

has names, zip codes, and gender of all voters.

I A grad student, Latanya Sweeney combined the two to

identify the governor of Massachusetts. Story is, she mailed

him his own health records!

I Dr. Sweeney now teaches at Harvard.

Example: Heath Records

Story Time:

I In 2000, Massachusetts released all State employee’s medical

records in an e↵ort for researchers to be able to study them.

I They wiped all ids, but kept zip codes, birthday, gender. Was

declared anonymized by the government.

I In Massachusetts, it was possible to buy voter data for $20. It

has names, zip codes, and gender of all voters.

I A grad student, Latanya Sweeney combined the two to

identify the governor of Massachusetts. Story is, she mailed

him his own health records!

I Dr. Sweeney now teaches at Harvard.

Example: Heath Records

Story Time:

I In 2000, Massachusetts released all State employee’s medical

records in an e↵ort for researchers to be able to study them.

I They wiped all ids, but kept zip codes, birthday, gender. Was

declared anonymized by the government.

I In Massachusetts, it was possible to buy voter data for $20. It

has names, zip codes, and gender of all voters.

I A grad student, Latanya Sweeney combined the two to

identify the governor of Massachusetts. Story is, she mailed

him his own health records!

I Dr. Sweeney now teaches at Harvard.

-

Example: Heath Records

Story Time:

I In 2000, Massachusetts released all State employee’s medical

records in an e↵ort for researchers to be able to study them.

I They wiped all ids, but kept zip codes, birthday, gender. Was

declared anonymized by the government.

I In Massachusetts, it was possible to buy voter data for $20. It

has names, zip codes, and gender of all voters.

I A grad student, Latanya Sweeney combined the two to

identify the governor of Massachusetts. Story is, she mailed

him his own health records!

I Dr. Sweeney now teaches at Harvard.

-

Example: Heath Records

Story Time:

I In 2000, Massachusetts released all State employee’s medical

records in an e↵ort for researchers to be able to study them.

I They wiped all ids, but kept zip codes, birthday, gender. Was

declared anonymized by the government.

I In Massachusetts, it was possible to buy voter data for $20. It

has names, zip codes, and gender of all voters.

I A grad student, Latanya Sweeney combined the two to

identify the governor of Massachusetts. Story is, she mailed

him his own health records!

I Dr. Sweeney now teaches at Harvard.

Example: Heath Records

Story Time:

I In 2000, Massachusetts released all State employee’s medical

records in an e↵ort for researchers to be able to study them.

I They wiped all ids, but kept zip codes, birthday, gender. Was

declared anonymized by the government.

I In Massachusetts, it was possible to buy voter data for $20. It

has names, zip codes, and gender of all voters.

I A grad student, Latanya Sweeney combined the two to

identify the governor of Massachusetts. Story is, she mailed

him his own health records!

I Dr. Sweeney now teaches at Harvard.

How to release data anonymouslywhile preserving individual

int

k - anonymity : Hate sat has public traits- -

{ age , Zip code, gender)categorical

private traits : has cancer,

has Covin - is

enforce atleast each person

has at least k - I other people✓ ( same publicity released

traits.

l - diversity i k - anonymity- -

i and each

grouphad l - diverse traits

.

e.g .Some have cancer

some don't-

issue either have cancer

ur have diabetes-

t.cl#ssil-dier-sib and the distribute.

of traits is t - close to

distribution of all people in

data .

Height of Sylvester Stallone-

. Information i Slg Stallone is height oof

the avenge TVJ man .

• Independent survey : Average height b men

-

in NJ s'

8"

Example: Netflix Prize

Story Time:

I In 2006, Netflix (e.g., DVDs) released awesome data sets

D1 = {huser-id, movie, date of grade, gradei}.And another set D2 = {huser-id, movie, date of gradei}.Wants researchers to predict grade on D2.

(Had another similar private data D3 to evaluate grades :

cross validation.)

I If certain improvement over Netflix’s algorithm, get $1 million!

I Led to lots of cool research!

I Raters of movies also rated on IMDB (w/ user id, time stamp)

I Researchers showed that by linking who rated similar sets of

movies, with similar scores and times, they could identify

many people.

I (maybe watched embarrassing films on Netflix, not listed on

IMDB)

I Class action lawsuit filed (lated dropped) against Netflix.

I Netflix Prize had proposed sequel, dropped in 2010 for more

privacy concerns.

Example: Netflix Prize

Story Time:

I In 2006, Netflix (e.g., DVDs) released awesome data sets

D1 = {huser-id, movie, date of grade, gradei}.And another set D2 = {huser-id, movie, date of gradei}.Wants researchers to predict grade on D2.

(Had another similar private data D3 to evaluate grades :

cross validation.)

I If certain improvement over Netflix’s algorithm, get $1 million!

I Led to lots of cool research!

I Raters of movies also rated on IMDB (w/ user id, time stamp)

I Researchers showed that by linking who rated similar sets of

movies, with similar scores and times, they could identify

many people.

I (maybe watched embarrassing films on Netflix, not listed on

IMDB)

I Class action lawsuit filed (lated dropped) against Netflix.

I Netflix Prize had proposed sequel, dropped in 2010 for more

privacy concerns.

-

# no grade

Example: Netflix Prize

Story Time:

I In 2006, Netflix (e.g., DVDs) released awesome data sets

D1 = {huser-id, movie, date of grade, gradei}.And another set D2 = {huser-id, movie, date of gradei}.Wants researchers to predict grade on D2.

(Had another similar private data D3 to evaluate grades :

cross validation.)

I If certain improvement over Netflix’s algorithm, get $1 million!

I Led to lots of cool research!

I Raters of movies also rated on IMDB (w/ user id, time stamp)

I Researchers showed that by linking who rated similar sets of

movies, with similar scores and times, they could identify

many people.

I (maybe watched embarrassing films on Netflix, not listed on

IMDB)

I Class action lawsuit filed (lated dropped) against Netflix.

I Netflix Prize had proposed sequel, dropped in 2010 for more

privacy concerns.

Example: Netflix Prize

Story Time:

I In 2006, Netflix (e.g., DVDs) released awesome data sets

D1 = {huser-id, movie, date of grade, gradei}.And another set D2 = {huser-id, movie, date of gradei}.Wants researchers to predict grade on D2.

(Had another similar private data D3 to evaluate grades :

cross validation.)

I If certain improvement over Netflix’s algorithm, get $1 million!

I Led to lots of cool research!

I Raters of movies also rated on IMDB (w/ user id, time stamp)

I Researchers showed that by linking who rated similar sets of

movies, with similar scores and times, they could identify

many people.

I (maybe watched embarrassing films on Netflix, not listed on

IMDB)

I Class action lawsuit filed (lated dropped) against Netflix.

I Netflix Prize had proposed sequel, dropped in 2010 for more

privacy concerns.

Example: Netflix Prize

Story Time:

I In 2006, Netflix (e.g., DVDs) released awesome data sets

D1 = {huser-id, movie, date of grade, gradei}.And another set D2 = {huser-id, movie, date of gradei}.Wants researchers to predict grade on D2.

(Had another similar private data D3 to evaluate grades :

cross validation.)

I If certain improvement over Netflix’s algorithm, get $1 million!

I Led to lots of cool research!

I Raters of movies also rated on IMDB (w/ user id, time stamp)

I Researchers showed that by linking who rated similar sets of

movies, with similar scores and times, they could identify

many people.

I (maybe watched embarrassing films on Netflix, not listed on

IMDB)

I Class action lawsuit filed (lated dropped) against Netflix.

I Netflix Prize had proposed sequel, dropped in 2010 for more

privacy concerns.

Example: Netflix Prize

Story Time:

I In 2006, Netflix (e.g., DVDs) released awesome data sets

D1 = {huser-id, movie, date of grade, gradei}.And another set D2 = {huser-id, movie, date of gradei}.Wants researchers to predict grade on D2.

(Had another similar private data D3 to evaluate grades :

cross validation.)

I If certain improvement over Netflix’s algorithm, get $1 million!

I Led to lots of cool research!

I Raters of movies also rated on IMDB (w/ user id, time stamp)

I Researchers showed that by linking who rated similar sets of

movies, with similar scores and times, they could identify

many people.

I (maybe watched embarrassing films on Netflix, not listed on

IMDB)

I Class action lawsuit filed (lated dropped) against Netflix.

I Netflix Prize had proposed sequel, dropped in 2010 for more

privacy concerns.

Example: Netflix Prize

Story Time:

I In 2006, Netflix (e.g., DVDs) released awesome data sets

D1 = {huser-id, movie, date of grade, gradei}.And another set D2 = {huser-id, movie, date of gradei}.Wants researchers to predict grade on D2.

(Had another similar private data D3 to evaluate grades :

cross validation.)

I If certain improvement over Netflix’s algorithm, get $1 million!

I Led to lots of cool research!

I Raters of movies also rated on IMDB (w/ user id, time stamp)

I Researchers showed that by linking who rated similar sets of

movies, with similar scores and times, they could identify

many people.

I (maybe watched embarrassing films on Netflix, not listed on

IMDB)

I Class action lawsuit filed (lated dropped) against Netflix.

I Netflix Prize had proposed sequel, dropped in 2010 for more

privacy concerns.

Example: Netflix Prize

Story Time:

I In 2006, Netflix (e.g., DVDs) released awesome data sets

D1 = {huser-id, movie, date of grade, gradei}.And another set D2 = {huser-id, movie, date of gradei}.Wants researchers to predict grade on D2.

(Had another similar private data D3 to evaluate grades :

cross validation.)

I If certain improvement over Netflix’s algorithm, get $1 million!

I Led to lots of cool research!

I Raters of movies also rated on IMDB (w/ user id, time stamp)

I Researchers showed that by linking who rated similar sets of

movies, with similar scores and times, they could identify

many people.

I (maybe watched embarrassing films on Netflix, not listed on

IMDB)

I Class action lawsuit filed (lated dropped) against Netflix.

I Netflix Prize had proposed sequel, dropped in 2010 for more

privacy concerns.

Example: Netflix Prize

Story Time:

I In 2006, Netflix (e.g., DVDs) released awesome data sets

D1 = {huser-id, movie, date of grade, gradei}.And another set D2 = {huser-id, movie, date of gradei}.Wants researchers to predict grade on D2.

(Had another similar private data D3 to evaluate grades :

cross validation.)

I If certain improvement over Netflix’s algorithm, get $1 million!

I Led to lots of cool research!

I Raters of movies also rated on IMDB (w/ user id, time stamp)

I Researchers showed that by linking who rated similar sets of

movies, with similar scores and times, they could identify

many people.

I (maybe watched embarrassing films on Netflix, not listed on

IMDB)

I Class action lawsuit filed (lated dropped) against Netflix.

I Netflix Prize had proposed sequel, dropped in 2010 for more

privacy concerns.

Differential Privacy

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