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Information Technology Program Aalto University, 2015 Dr. Joni Salminen [email protected], tel. +358 44 06 36 468 DIGITAL ANALYTICS 1

Digital analytics: Analytics problems (Lecture 9)

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Information Technology Program

Aalto University, 2015

Dr. Joni Salminen

[email protected], tel. +358 44 06 36 468

DIGITAL ANALYTICS

1

PROBLEMS OF ANALYTICS

1

I’ve waited for

this all my life…

The philosophy

• In a given field, there are x problems that prevent you

from reaching outcome y.

• Solve x, then y follows.

• (In my dissertation, the point was though that solving

x{0} might lead to x{1} problems.)

2

10 interesting analytics problems…

1. aggregation problem

2. last click fallacy

3. vanity metrics

4. analysis paralysis

5. multichannel problem

6. bounce problem

7. data discrepancy problem

8. optimization goal dilemma

9. zero value problem

10. churn problem

3

OMG. It’s so

good I’m going

to faint!

1. aggregation problem = seeing the

general trend, but not understanding

why it took place

4

segmentating data (e.g.

channel, campaign,

geography, time (cohorts))

Solution:

Simpson’s paradox (Loszewski, 2013)

5

Impressions Click CTR Ad 1 10,600 125 1.18%

Ad 2 7,500 125 1.67%

Aggregate data

Impressions Clicks CTR

Ad 1 600 25 4.20%

Ad 2 2,500 100 4.00%

Ad group 1

Impressions Clicks CTR

Ad 1 10,000 100 1.00%

Ad 2 5,000 25 0.50%

Ad group 2

Solution:

2. last click fallacy = taking only the last

interaction into account

6

attribution modelling

3. vanity metrics = reporting ”show off”

metrics as oppose to relevant ones

7

choosing relevant KPIs Solution:

4. analysis paralysis = the inability to

know which data to analyze or where

to start from

8

choosing actionable

metrics

Solution:

5. multichannel problem = losing track

of users when they move between

online and offline

9

Universal Analytics Solution:

6. bounce problem = deducting based

on a poor bounce rate that the

usability of a website is bad, even

though in reality it is not

10

correcting for bounce

measurement

Solution:

Solving the bounce problem (Salminen,

2015)

So, you have a landing page designed for immediate

interaction (no further clicks). And you have a high

bounce rate, indicating a bad user experience. To

improve your measurement of user experience, create

an event that pings your analytics software in case a

user makes an on-page action (e.g. video viewing).

Alternatively, ping based on visit duration, e.g. create an

event of spending 1min on the page. This will in effect

lower your reported bounce rate by degree of those user

actions.

(https://www.linkedin.com/pulse/bounce-problem-how-track-simple-landing-

pages-joni-salminen?trk=mp-reader-card)

11

7. data discrepancy problem = getting

different numbers from different

platforms

12

understanding definitions

& limitations, using UTM

parameters

Solution:

Interpreting metrics: CPC

• Avg. CPC (FB): 0,10€

• Avg. CPC (AdW): 0,20€

• Which one is better?

• There is no way to know with this information. Why?

13

Definitions

• Google: a click takes place when a user clicks the

link on an ad.

• Facebook: a click takes place when a user clicks the

link on an ad, or likes it, or comments it, or shares it.

• So, what is interepreted by an advertiser asa”click”

is in fact a”website click”inFacebook’s system.

14

The result of defining ’clicks’ differently

”I also have been paying for 45 clicks per week

from FB, while my Wordpress Stats only reports 11

from Facebook in total for 30 days. While the

Google Adwords paid per click vs. stats is exact. I

have specifically set it up to pay for only a website

link, and not post engagement etc. I think you are

taking us for a ride, and I would like to be

reimbursed thanks.”

15

Are they

charging me for

fake clicks??!

Interpreting metrics: CPC

• Say both campaigns had 100 clicks. Out of 100, FB

had 30 website clicks. (All Google clicks are website

clicks.)

• Re-calculate: (100 x 0,10)/30 = 0,30€

• Now it’s:

– CPC (FB): 0,30€

– CPC (AdW): 0,20€

16

Interpreting metrics: CPC

(Facebook has recently re-defined its CPC definition to

match that of Google. Still, it makes sense to always

verify what is being measured by a given metric, and

acknowledge different platforms may use different

calculations.)

17

It makes a good

bedtime

reading.

Conversion tracking in Facebook: particular

shit

“Aswith actions, Facebook tracks conversions that

happen within 1 day, 7 days, and 28 days after a person

clicks on an ad, and 1 day, 7 days, and 28 days after

viewing an ad.”

• The result: over-reporting conversions! (similar to

iSales in many affiliate networks)

• The solution: change lookback window in reports to

1 day.

• What do you think is the correct lookback window?

18

The problem of short lookback windows

(Goldberg, 2013)

“Whileour natural tendency is to generally use short

lookback periods (say, 7 days or a month, for example),

on an attributed basis, it’s important to lengthen this

out.Thereasonissimple…Ifcustomerslagabitbefore

squeezingthetrigger,it’sgoingtotaketimefor

introducer and influencer counts and values to appear. I

like to use 60-90 days as a lookback period on

keywords/ad groups that I know have a tendency to

introduce or influence a conversion as opposed to

closing, so that I can capture as much information as

possible into my bid rule.”

19

How long lookback window should you

choose?

• Regularly, I’d say all historical data

• However, what’s the problem with this approach?

• It can hide a current trend.

20

Hmm… a related issue of different reported

metrics is information asymmetry. Who

knows what that means?

• One party has more information than the other.

– Party A: The advertiser

– Party B: The advertising platform

• Which one has information advantage?

21

Hmm… a related issue of different reported

metrics is information asymmetry. Who

knows what that means?

• Party A: The advertiser

• Party B: The advertising platform

• Because of this information asymmetry, there arises

what we call moral hazard (criteria of delegation and

lack of monitoring also fulfilled).

• In other words, they can report whatever the hell they

want! How would you know?

22

Solutions to moral hazard?

A major solution to moral hazard is transparency. For

example, in digital marketing frequent audits are helpful.

The mere knowledge of being audited regularly will

increase the incentive of an agency (as in: advertising

agency) to stay honest. Obviously, the auditor needs to

be an independent 3rd party with adequate skills to

evaluate the account.

Thankfully,theriskof“gettingcaught”andthe

consecutive loss of trust are likely to keep the big

platformsincheck.Theywanttoavoidthelemon’s

market problem at any cost.

23

Click fraud reduction (Facebook, 2015)

“Facebook Ads click quality measures

We have measures in place to reduce invalid clicks and

may filter out some clicks and impressions. This may

result in third-party packages over-counting relative to

the clicks reported by Facebook Ads. We may invalidate

repetitive or incomplete clicks, and we cap the number

of times any user can see or click on your ad or

sponsored story in a day.”

24

So they say!

…but still, they may passively approve

some bot traffic

• e.g., bounce rate in GDN +80%!

• e.g., Facebook botgate (which, by the way, died

surprisingly fast)

25

8. optimization goal dilemma =

optimizing for platform-specific

metrics leads to un-optimal business

results, and vice versa.

26

Solution: making a

judgment call

Optimization for platform metrics can be in

conflict with optimizing for business goals

27

Which ad is more successful?

Ad A Ad B

Quality score 10 3

CTR 10 % 3 %

Impressions 1000 1000

Clicks 100 30

Conversions 15 15

Revenue 1500 € 1500 €

Cost 500 € 150 €

Optimization for platform metrics can be in

conflict with optimizing for business goals

28

Ad A Ad B

Quality score 10 3

CTR 10 % 3 %

Impressions 1000 1000

Clicks 100 30

Conversions 15 15

Revenue 1500 € 1500 €

Cost 500 € 150 €

ROI 200 900%

The metric conflict can be seen as an issue

of local vs. global maximum

• This is a common computer science problem

– Platform-specific metrics: local maximum

– Business goals: global maximum

• It can be very very hard to achieve a global

maximum, but metrics should be chosen to support

the path towards it…

29

…so, I just choose the most important

business KPI, right?

• Not necessarily. (Need to look at the whole funnel.)

30

Which one, leads

or applications,

predict closes?

(Yamaguchi,

2013)

9. zero value problem = a marketing

channel shows poor results in direct

conversions (usually sales); as a

result, investments are stopped and

after a while results in other channels

decrease as well

31

proxy metrics Solution:

Why does the problem take place?

because channels are not isolated, but there are

spillover effects

a. horizontal spillover effects = between channels (e.g.,

Facebook creates interest, Google captures it)

b. vertical spillover effects = between funnel steps (e.g.,

conversion optimization and traffic generation; the

more you improve the bottom funnel metrics, the

more higher funnel metrics improve as well (but not

vice versa))

32

When & Why To Use Proxy Metrics

(Yamaguchi, 2013)

1. “Short-Term Goals: There are cases where a proportion of the

marketing budget is allocated […]towardincreasing higher-funnel

metrics such as leads or registrations under the assumption that

these efforts will eventually lead to a greater revenue base.

2. Trackability: For offline, or when there is a long conversion funnel

that involves non-digital steps such as call centers, lower-funnel

metrics may be difficult to link back to marketing touchpoint(s).

3. Attribution Bias: Different channels, or even individual campaigns

within a channel, are located at different points in the conversion

funnel. As a result, assessing performance only using final

conversion results in attribution […]notreflective of actual impact.

4. Conversion Delay: If the conversion funnel is long, there may be a

significant delay between top-of-funnel conversion to final conversion

in the order of weeks or even months. For these cases, proxy metrics

are useful for getting more timely feedback of campaign

performance.”

33

The problem of deferred conversion

34

~60% of conversions are within the

first day of click, but a considerable

amount only after a week or more

(case: ElämysLahjat.fi)

Path length report shows the number of

visits leading to conversions

35

Typically less than half of conversions

are made during the first visit (case:

ElämysLahjat.fi)

10.churn problem = a special case of

aggregation problem; the aggregate

numbers show growth whereas in

reality we are losing customers

36

cohort analysis Solution:

The basics of churn (WikiHow, 2015)

“Monitoringcustomerchurnisveryimportant,sinceitis

normally easier to retain customers than it is to

secure new ones. By calculating the churn rate

regularly, and investigating the reasons for that rate, it

may be possible to make changes in the way customers

are managed and reduce that rate in future.”

37

Makes sense.

You marketers

are so fine!

The growth paradox (York, 2010)

38

Should churn rate

remain constant, it

leads into an

increasingly large

quantity of churned

customers, regardless

of how much the

number of new

customers increases

Essentially, it’s like

pouring water into a

leaking bucket.

So what? So,

increasing retention

(loyalty) is super

important.

The trap of customer acquisition (York,

2010)

39

Growth slows

down inevitably

unless the number

of acquired

customers grows

faster than churn.

Churn affects

how much we

can pay for new

customers!

Essentially, churn problem is another

variant of the good ’ol aggregation problem

“Whenyou compare to the week 1 to week 2 cohort, you can

tell that 1) there was a 25% increase in new users (100k to

125k), and that the retention rate DECREASED to 40%

(50k/100k versus 50k/125k). This would be a red flag that your

site was sucking, even if your aggregate stats looked good:

In either case, this might hint at a bad systematic condition

within the site, but ultimately the aggregate numbers hide

the problem. In either case, not being able to acquire and retain

brand new users is a problem, and without measuring the

groups separately, it seems impossible to assess the true

situation.”(Chen, 2007)

40

How to calculate churn? (WikiHow, 2015)

“Customerchurn is normally presented as a percentage.

For example, if a company with 100 customers should

lose 10 clients but gain 7, this amounts to a net loss of

3 clients, and a customer churn of 3 percent. If the

same company lost 10 clients but gained 15, this would

constitute a net gain of 5 clients and result in a negative

churn rate.”

41

Customers both

come and go.

How to calculate churn rate? An example

42

Include both customer churn and revenue

churn (Macleod, 2012)

43

Remember: loyalty is the opposite of churn!

• 𝐿 = 1 − 𝑐, in which

• L = loyalty

• c = churn

44

Makes sense.

Why not use

loyalty then?

What is a cohort?

“Acohort is a group of people who share a

common characteristic or experience within a

defined period (e.g., are born, are exposed to a

drug or vaccine or pollutant, or undergo a certain

medical procedure). Thus a group of people who

were born on a day or in a particular period, say

1948, form a birth cohort.”(Wikipedia,2015)

45

I’m in the cohort of

1985. Compared to my

cohort average, I must

say I rock. Thug for

life, baby!

Cohort: an example (Cutroni, 2012)

“Here’san ecommerce example. If I was an ecommerce

business owner I would want to create a cohort of

customers who make their first purchase on Black

Friday. This cohort is important because they made

their first purchase during a very important time, the

holiday buying season.”

For example, comparing loyalty or lifetime value of

people buying/joining in a given day/week/month.

46

How is cohort segmentation different from

user segmentation?

• Well, it is a form of user segmentation

• But, segmentation criteria in cohort analysis needs to

include TIME (other criteria can be behavior, source,

etc.)

• For example,

– bought on December 2013

– visited the site January 2014

– came from Facebook in 2012

47

Cohort analysis: an example (Cutroni, 2012)

“Froman analysis perspective we want to segment this

group to observe their behavior over a longer period of

time.

• Do these customer behave differently?

• How do they differ from customers that buy at

other times of the year?

• Do they buy multiple times? Do they spend the

same amount?”

48

Why use cohorts?

• Well, as said, there are several ways why time of first

interaction would affect people’s behavior. Also our

actions differ:

– Monthly marketing campaigns differ

– Changes to product

– Gives a view to the change, not the aggregate picture

• Ultimately, cohorts segment by time and can

therefore uncover time-related aggregation issues.

• Free to choose criteria: demographics, source,

month, week…(but always tied to time)

49

Let’s practice!

1. Open the files (Exercise 4.xlsx, churn_instructions.txt)

2. Insert the data

3. Answer the questions

50

The setting • You're the marketing manager in a SaaS startup. You've done different

marketing campaigns throughout the year, and now have to evaluate their

performance in terms of user loyalty.

• Here's the information you have:

• In January, you closed 10 customers.

• Due to great marketing, you doubled your monthly new customers each month until

the end of May.

• After that, the number of new customers settled to a healthy 100 per month.

• It stayed at that level until the end of the year.

• From January's customers, you lost two each month.

• For February's customers, the loaylty rate after each month was 70%. (Round to

even numbers.)

• March customers had a churn rate of 20% throughout their known lifetime. (Round

to even numbers.)

• In April, you ran a discount campaign at Groupon. The customers were only about

the price, and none returned the following month.

• For May's cohort, the churn rate was 40% for the first two months, but after that it

stabilized to 20%. (Round to even numbers.)

• In June, you launched a loyalty campaign which rewards sticking customers with a

monthly free gift. As a result, the monthly churn for these users is 5%. (Round to

even numbers.)

• In all other cohorts, you lost 10 customers per month.

51

Now, answer the questions

How many customers we had in total during the whole

year?

How many customers does the company have in the

end of December?

What is the churn rate for July?

How many customers churned in October?

What was the overall churn rate for the whole year?

How many customers were lost during the year?

How many (in %) of February’s customers are still

around in September?

Which cohort performs the best? Why?

52

The answers

How many customers we had in total during the whole

year? 1010

How many customers does the company have in the

end of December? 481

What is the churn rate for July? 11%

How many customers churned in October? 52

What was the overall churn rate for the whole year? 52%

How many customers were lost during the year? 529

How many (in %) of February’s customers are still

around in September? 5%

Which cohort performs the best? Why? June, probably

because of the loyalty program.

53

In regular churn calculations, there’s no

problem. You just input numbers you have.

The problem emerges when you have to

predict.

• When using relative churn (%), it only approaches

zero. How to solve?

– constant (e.g., losing 20 customers per month)

– theory of lifetime prediction? (lim →0)(survival

analysis)

– maximum lifetime assumption (e.g., 5 years)

– using running average

• in prediction, it would be realistic to consider that

churn, whether constant or relative, is not static by

nature (polynomial or rational function)

54

Why does it matter? (1. Extrapolating, 2.

Maximum CAC)

“Atypical pattern found in subscription businesses is that after a

steep drop off after an initial period, month-on-month attrition

rates tend to level off.

If you see a pattern like this, you can extrapolate forward using the

same month-on-month attrition across several years. As you can

see in the model, we extrapolate an average lifetime of 9.77 months by

extrapolating forward over 5 years of data.

So if you were a subscription business charging $20/month with 90%

gross margins (after accounting for customer service costs for

example), then you would attribute a lifetime value for a new

customer of 9.77 x $20 x 90% = $176. This sets an upper bound of

what you would be willing to pay to acquire a customer (although

in practice, you would prefer to see a ratio of CAC/LTV in the 25-35%

range).”(Liew, 2010)

55

The time discrepancy causes problems

• Problem: how much can you spend on customer

acquisition?

• Problem: customer acquisition needs to be paid

NOW, but the money will be recovered only during

the lifetime

– paradox: it’s possible to have a situation in which the

more a company gains new customers, the more

unprofitable it becomes

– tactics: ask customers pay the whole year beforehand

(discount); upselling; buffer (VC money)

• Problem: churn

– the absolute number of lost customer increases with

the number of customers, even if the churn-% remains

stable

– how to minimize churn? 56