counteracting the negative effect of form auto-completion on the privacy calculus

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Counteracting the negative effect of form auto-completion on the privacy calculus Bart Knijnenburg, Alfred Kobsa, Hongxia Jin

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Talk given in the "Privacy Calculus" session of the ICIS2013 conference

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Page 1: Counteracting the negative effect of form auto-completion on the privacy calculus

Counteracting the negative effect of form auto-completion on the privacy calculus

Bart Knijnenburg, Alfred Kobsa, Hongxia Jin

Page 2: Counteracting the negative effect of form auto-completion on the privacy calculus

Form auto-completion: the bright side

Modern browsers offer an auto-completion feature that reduces the effort of filling out web forms

�2

Bart

Page 3: Counteracting the negative effect of form auto-completion on the privacy calculus

Form auto-completion: the bright side

Modern browsers offer an auto-completion feature that reduces the effort of filling out web forms

!Imagine such tools could fill out any form, on any website

�3

Page 4: Counteracting the negative effect of form auto-completion on the privacy calculus

Form auto-completion: the bright side

Modern browsers offer an auto-completion feature that reduces the effort of filling out web forms

!Imagine such tools could fill out any form, on any website

!This would be particularly useful for mobile browsers

�4

Page 5: Counteracting the negative effect of form auto-completion on the privacy calculus

Form auto-completion: the dark side

Preibusch et al. (2012) warn that such auto-completion tools may cause users to complete more form fields than they intended

Page 6: Counteracting the negative effect of form auto-completion on the privacy calculus

Form auto-completion: the dark side

Preibusch et al. (2012) warn that such auto-completion tools may cause users to complete more form fields than they intended

!Auto-completion tools make it so easy to submit a fully completed form that users may skip weighing the benefits and risk of disclosing a certain piece of information in a specific situation (privacy calculus!)

Page 7: Counteracting the negative effect of form auto-completion on the privacy calculus

Form auto-completion: the dark side

Preibusch et al. (2012) warn that such auto-completion tools may cause users to complete more form fields than they intended

!Auto-completion tools make it so easy to submit a fully completed form that users may skip weighing the benefits and risk of disclosing a certain piece of information in a specific situation (privacy calculus!)

!Can we overcome these problems with a better auto-completion tool?

Page 8: Counteracting the negative effect of form auto-completion on the privacy calculus

Research outline

We introduce two new tools that we hypothesize will reinstate the privacy calculus

!Specifically, we compare three auto-completion tools: – Auto FormFiller (automatically fills

fields, users can remove manually)  – Remove FormFiller (same but

users can click to remove each field)  

– Add FormFiller (no automatic filling, users can click a button to fill each field)

�8

Please tell us more about yourselfBlogHeroes  will  assign  a  "guild"  to  you  based  on  the  information  you  provide  below.  Note  that  noneof  the  fields  are  required,  but  our  classification  will  be  better  if  you  provide  more  information.

General  info  about  mePlease  provide  some  background  info  to  get  our  matching  process  started.

Name  (first): John (last): Smith

E-­mail  address: [email protected]

Gender: Male

Age  (years): 23

Address: 123 Main St.City: New York State: NY Zip: 12345

What  I  do  for  a  livingSome  guilds  write  about  their  jobs.  Tell  us  more  about  yours,  and  we  can  provide  a  better  match.

Employment  status: Employed for wages

Experience  (years): 5

Current/previous  job: Researcher Sector: Education / training / library

Income  level: between $50K and $100K/year

Education: Doctoral

My  healthSome  guilds  write  about  their  health.  Providing  us  with  some  info  will  help  us  match  them  to  you.

Physical  health: About average

Dietary  restrictions: allergic to nuts

Birth  control  usage: None

> For employers

> For investors

> Contact

> About us

Please  enter  your  informationI WRK will find jobs based on the information you enter on this form.None of the items on the form are required, but if you provide moreinformation the jobs will be a better match.

GENERAL AND CONTACT INFO

General and contact information

FIRST NAME

JohnLAST NAME

Smith clear

AGE

23 clear

GENDER

Male clear

E-MAIL ADDRESS

[email protected] clear

ADDRESS

123 Main St.CITY

New YorkSTATE

NYZIP

12345 clear

WORK EXPERIENCE

Please tell us about your education and work experience, so that wecan find a suitable job for you.

HIGHEST DEGREE EARNED

Doctoral clear

CURRENT EMPLOYMENT STATUS

Employed for wages clear

CURRENT/PREVIOUS JOB

ResearcherSECTOR

Education, library, or training clear

EXPERIENCE (IN YEARS)5 clear

Enter your details, please

Your personal Codacare health insurance policy will be based on theinformation you provide. Please note that none of the items arerequired, but the insurance will be better tailored to your needs if youprovide more information.

General information

Please provide your general information.

Name (first): (last):fill

Address:

fillCity: State: Zip:

Gender:fill

Age:fill

E-‐mail:fill

Health

Please answer the following questions about your health. This is important to find thecorrect care package.

Birth control usage:fill

Weight (lbs):fill

Page 9: Counteracting the negative effect of form auto-completion on the privacy calculus

Research outline

People base their information disclosure decision on the perceived risk and relevance of the information

Perceived risk and relevance (and thus disclosure)

depend on the purpose-specificity of the request

The effect of risk and relevance is moderated by tool type: disclosure is more “calculated” when the add and remove tools are used

Page 10: Counteracting the negative effect of form auto-completion on the privacy calculus

Research model

Website

Item type

Disclosure

Risk

Relevance

Tool type

Page 11: Counteracting the negative effect of form auto-completion on the privacy calculus

Research model

Website

Item type

Disclosure

Risk

Relevance

Tool type

perceived risk and relevance

Page 12: Counteracting the negative effect of form auto-completion on the privacy calculus

Research model

Website

Item type

Disclosure

Risk

Relevance

Tool type

purpose-specificity

Page 13: Counteracting the negative effect of form auto-completion on the privacy calculus

Research model

Website

Item type

Disclosure

Risk

Relevance

Tool type

moderation by tool type

Page 14: Counteracting the negative effect of form auto-completion on the privacy calculus

�14

What causes information disclosure?

Page 15: Counteracting the negative effect of form auto-completion on the privacy calculus

What causes information disclosure?

Typical answer: privacy calculus (Laufer and Wolfe 1977)

�15

Page 16: Counteracting the negative effect of form auto-completion on the privacy calculus

What causes information disclosure?

Typical answer: privacy calculus (Laufer and Wolfe 1977)

!Privacy calculus is like utility maximization (Li 2012): people trade off the different aspects and then choose the option that maximizes their utility (Bettman et al. 1998; Simon 1959)

�16

Page 17: Counteracting the negative effect of form auto-completion on the privacy calculus

What causes information disclosure?

Typical answer: privacy calculus (Laufer and Wolfe 1977)

!Privacy calculus is like utility maximization (Li 2012): people trade off the different aspects and then choose the option that maximizes their utility (Bettman et al. 1998; Simon 1959)

!So what are these aspects that people trade off?

�17

Page 18: Counteracting the negative effect of form auto-completion on the privacy calculus

What causes information disclosure?

Risk !Operationalization:

Providing my [item] to [site] is:

(-3 = very risky; +3 = very safe)

!!Relevance !Operationalization:

The fact that [site] asked for my [item] was:

(-3 = very inappropriate; +3 very appropriate) �18

Disclosure

Risk

Relevance

Page 19: Counteracting the negative effect of form auto-completion on the privacy calculus

�19

What causes information disclosure?

perceived risk and relevance

Page 20: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

What causes information disclosure?

perceived risk and relevance

Page 21: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

On web forms, users selectively disclose different types of information in different extent to different types of websites (Hsu 2006)

Page 22: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

On web forms, users selectively disclose different types of information in different extent to different types of websites (Hsu 2006)

!Social media users also share selectively with others, depending on the purpose of the information (Olson et al. 2005)

Page 23: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

On web forms, users selectively disclose different types of information in different extent to different types of websites (Hsu 2006)

!Social media users also share selectively with others, depending on the purpose of the information (Olson et al. 2005)

!Does purpose-specificity play a role in commercial privacy as well?

Page 24: Counteracting the negative effect of form auto-completion on the privacy calculus

Please tell us more about yourselfBlogHeroes  will  assign  a  "guild"  to  you  based  on  the  information  you  provide  below.  Note  that  noneof  the  fields  are  required,  but  our  classification  will  be  better  if  you  provide  more  information.

General  info  about  mePlease  provide  some  background  info  to  get  our  matching  process  started.

Name  (first): John (last): Smith

E-­mail  address: [email protected]

Gender: Male

Age  (years): 23

Address: 123 Main St.City: New York State: NY Zip: 12345

What  I  do  for  a  livingSome  guilds  write  about  their  jobs.  Tell  us  more  about  yours,  and  we  can  provide  a  better  match.

Employment  status: Employed for wages

Experience  (years): 5

Current/previous  job: Researcher Sector: Education / training / library

Income  level: between $50K and $100K/year

Education: Doctoral

My  healthSome  guilds  write  about  their  health.  Providing  us  with  some  info  will  help  us  match  them  to  you.

Physical  health: About average

Dietary  restrictions: allergic to nuts

Birth  control  usage: None

But what causes risk and relevance?

In our experiment, participants: – entered a wide range of info into an auto-completion tool

– tested the tool on one of three websites

Create  a  ProfilePlease  create  your  profile  by  entering  your  information  below.Note  that  FormFiller  will  store  the  information  locally  on  your  device,  and  only  for  the  duration  ofthis  study.  We  will  never  submit  any  forms  automatically  or  disclose  this  information  to  otherswithout  your  active  involvement.

About  you:

First  name: Last  name:

Gender:

Age:

Address:

City: State: Zip:

E-­‐‑mail:

Phone:

Tastes  and  Preferences:

Favorite  movie:

Favorite  band/artist:

Favorite  food:

Favorite  weekendpastime:

Last  holiday  location:

Political  views:

Work  and  education:

Current/previous  job: Sector:

Employment  status:

> For employers

> For investors

> Contact

> About us

Please  enter  your  informationI WRK will find jobs based on the information you enter on this form.None of the items on the form are required, but if you provide moreinformation the jobs will be a better match.

GENERAL AND CONTACT INFO

General and contact information

FIRST NAME

JohnLAST NAME

Smith clear

AGE

23 clear

GENDER

Male clear

E-MAIL ADDRESS

[email protected] clear

ADDRESS

123 Main St.CITY

New YorkSTATE

NYZIP

12345 clear

WORK EXPERIENCE

Please tell us about your education and work experience, so that wecan find a suitable job for you.

HIGHEST DEGREE EARNED

Doctoral clear

CURRENT EMPLOYMENT STATUS

Employed for wages clear

CURRENT/PREVIOUS JOB

ResearcherSECTOR

Education, library, or training clear

EXPERIENCE (IN YEARS)5 clear

Enter your details, please

Your personal Codacare health insurance policy will be based on theinformation you provide. Please note that none of the items arerequired, but the insurance will be better tailored to your needs if youprovide more information.

General information

Please provide your general information.

Name (first): (last):fill

Address:

fillCity: State: Zip:

Gender:fill

Age:fill

E-‐mail:fill

Health

Please answer the following questions about your health. This is important to find thecorrect care package.

Birth control usage:fill

Weight (lbs):fill

Page 25: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

In our experiment, participants: – entered a wide range of info into an auto-completion tool  – tested the tool on one of three websites

Please tell us more about yourselfBlogHeroes  will  assign  a  "guild"  to  you  based  on  the  information  you  provide  below.  Note  that  noneof  the  fields  are  required,  but  our  classification  will  be  better  if  you  provide  more  information.

General  info  about  mePlease  provide  some  background  info  to  get  our  matching  process  started.

Name  (first): John (last): Smith

E-­mail  address: [email protected]

Gender: Male

Age  (years): 23

Address: 123 Main St.City: New York State: NY Zip: 12345

What  I  do  for  a  livingSome  guilds  write  about  their  jobs.  Tell  us  more  about  yours,  and  we  can  provide  a  better  match.

Employment  status: Employed for wages

Experience  (years): 5

Current/previous  job: Researcher Sector: Education / training / library

Income  level: between $50K and $100K/year

Education: Doctoral

My  healthSome  guilds  write  about  their  health.  Providing  us  with  some  info  will  help  us  match  them  to  you.

Physical  health: About average

Dietary  restrictions: allergic to nuts

Birth  control  usage: None

> For employers

> For investors

> Contact

> About us

Please  enter  your  informationI WRK will find jobs based on the information you enter on this form.None of the items on the form are required, but if you provide moreinformation the jobs will be a better match.

GENERAL AND CONTACT INFO

General and contact information

FIRST NAME

JohnLAST NAME

Smith clear

AGE

23 clear

GENDER

Male clear

E-MAIL ADDRESS

[email protected] clear

ADDRESS

123 Main St.CITY

New YorkSTATE

NYZIP

12345 clear

WORK EXPERIENCE

Please tell us about your education and work experience, so that wecan find a suitable job for you.

HIGHEST DEGREE EARNED

Doctoral clear

CURRENT EMPLOYMENT STATUS

Employed for wages clear

CURRENT/PREVIOUS JOB

ResearcherSECTOR

Education, library, or training clear

EXPERIENCE (IN YEARS)5 clear

Enter your details, please

Your personal Codacare health insurance policy will be based on theinformation you provide. Please note that none of the items arerequired, but the insurance will be better tailored to your needs if youprovide more information.

General information

Please provide your general information.

Name (first): (last):fill

Address:

fillCity: State: Zip:

Gender:fill

Age:fill

E-‐mail:fill

Health

Please answer the following questions about your health. This is important to find thecorrect care package.

Birth control usage:fill

Weight (lbs):fill

Page 26: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

In our experiment, participants: – entered a wide range of info into an auto-completion tool  – tested the tool on one of three websites  

Websites correspond to a particular type of info: – blogging community ⋍ personal interest items  – job search website ⋍ job skills items  – health insurer ⋍ health record items

Please tell us more about yourselfBlogHeroes  will  assign  a  "guild"  to  you  based  on  the  information  you  provide  below.  Note  that  noneof  the  fields  are  required,  but  our  classification  will  be  better  if  you  provide  more  information.

General  info  about  mePlease  provide  some  background  info  to  get  our  matching  process  started.

Name  (first): John (last): Smith

E-­mail  address: [email protected]

Gender: Male

Age  (years): 23

Address: 123 Main St.City: New York State: NY Zip: 12345

What  I  do  for  a  livingSome  guilds  write  about  their  jobs.  Tell  us  more  about  yours,  and  we  can  provide  a  better  match.

Employment  status: Employed for wages

Experience  (years): 5

Current/previous  job: Researcher Sector: Education / training / library

Income  level: between $50K and $100K/year

Education: Doctoral

My  healthSome  guilds  write  about  their  health.  Providing  us  with  some  info  will  help  us  match  them  to  you.

Physical  health: About average

Dietary  restrictions: allergic to nuts

Birth  control  usage: None

> For employers

> For investors

> Contact

> About us

Please  enter  your  informationI WRK will find jobs based on the information you enter on this form.None of the items on the form are required, but if you provide moreinformation the jobs will be a better match.

GENERAL AND CONTACT INFO

General and contact information

FIRST NAME

JohnLAST NAME

Smith clear

AGE

23 clear

GENDER

Male clear

E-MAIL ADDRESS

[email protected] clear

ADDRESS

123 Main St.CITY

New YorkSTATE

NYZIP

12345 clear

WORK EXPERIENCE

Please tell us about your education and work experience, so that wecan find a suitable job for you.

HIGHEST DEGREE EARNED

Doctoral clear

CURRENT EMPLOYMENT STATUS

Employed for wages clear

CURRENT/PREVIOUS JOB

ResearcherSECTOR

Education, library, or training clear

EXPERIENCE (IN YEARS)5 clear

Enter your details, please

Your personal Codacare health insurance policy will be based on theinformation you provide. Please note that none of the items arerequired, but the insurance will be better tailored to your needs if youprovide more information.

General information

Please provide your general information.

Name (first): (last):fill

Address:

fillCity: State: Zip:

Gender:fill

Age:fill

E-‐mail:fill

Health

Please answer the following questions about your health. This is important to find thecorrect care package.

Birth control usage:fill

Weight (lbs):fill

Page 27: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

Purpose-specificity will look like an interaction effect between Website and Item type

!!When the type of information requested matches the purpose of the website: – perceived risk will be lower  – perceived relevance will be higher

– people will be more likely to disclose the item

Website

Item type

Risk

Relevance

Page 28: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

Purpose-specificity will look like an interaction effect between Website and Item type

!!When the type of information requested matches the purpose of the website: – perceived risk will be lower  – perceived relevance will be higher

– people will be more likely to disclose the item

Website

Item type

Disclosure

Risk

Relevance

Page 29: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

Website

Item type

Disclosure

Risk

Relevance

odds: 0.818***

odds: 1.079***

see next slide

Model tested with 543 Mechanical Turk participants

�29

χ2(12) = 11.929, p = .451; CFI = 1.00, TLI = 1.00; RMSEA < .001, 90% CI: [.000, .011]

Page 30: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

When the type of item matches the purpose of the website, people perceive lower risk and higher relevance

Counteracting the negative privacy effect of form auto-completion

Thirty Fourth International Conference on Information Systems, Milan 2013 11

Figure 3. Perceived Risk and Perceived Relevance per Website and Item type. The arrows point to the matching item types. Error bars are ± 1 Standard Error.

Regarding perceived Risk, we find that the interaction between Website and Item type is significant (χ2(6) = 246.41, p < .0001). Moreover, for each website, the non-matching item types are perceived as significantly more risky than the matching item type. Also, for each item type, the non-matching websites are perceived as significantly more risky than the matching website13. H3 is thus supported.

Likewise, the interaction between Website and Item type is also significant for Perceived Relevance (χ2(6) = 913.47, p < .0001). For each website, the non-matching item types are perceived as significantly less relevant than the matching item type, and for each item type, the non-matching websites are perceived as significantly less relevant than the matching website. H4 is thus supported as well.

H5+H6. Tool type ! Disclosure

The last row in Table 2 presents the effect of Tool type on Disclosure. Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 6.3% higher for users of the Add tool than for users of the Remove tool, although this effect not significant (p = .631). Surprisingly then, H5 is rejected: there is no significant difference in Disclosure between the Add and Remove tools.

The planned contrast between the traditional Auto tool and the alternative tools is significant (χ2(1) = 4.037, p = .045). Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 24.0% lower for users of the Remove tool compared to users of the Auto tool, a small (d = .165) but significant (p = .047) effect. The odds of Disclosure are 18.9% lower for users of the Add tool compared to users of the Auto tool, a small (d = .107) effect that is not significant (p = .130). H6 is thus partially supported: Disclosure is indeed significantly higher for the Auto tool than for the Remove tool.

Hypotheses 7 and 8

To test H7 and H8, we introduce the interaction between Tool type and Perceived Risk and Relevance (dashed lines) to the path model described in Figure 2. Unfortunately, due to the high correlation between Perceived Risk and Perceived Relevance, we were unable to fit a model that includes both effects. We therefore introduce each effect to the model separately.

H7. Tool type × Perceived Risk ! Disclosure

To model the interaction between Tool type and Perceived Risk, we create a multiple group model, comparing the Add and Remove groups against the Auto group, fixing all parameters except for the intercept and the effect of Perceived Risk. This model again has an excellent fit (χ2(86) = 99.443, p = .152; CFI = .990, TLI = .988; RMSEA = .007, 90% CI: [.000, .013]). 13 To adjust for multiple comparisons, we compared the p-values in Tables 3-5 against Bonferroni-Holm corrected α levels; see http://en.wikipedia.org/wiki/Holm-Bonferroni_method.

80% 85% 90% 95% 100%

Contact info Interests Job skills Health record

" " " -3

-2

-1

0

1

2

3

BlogHeroes I♡WRK Codacare

Perceived risk

# # #

-3

-2

-1

0

1

2

3

BlogHeroes I♡WRK Codacare

Perceived relevance

Counteracting the negative privacy effect of form auto-completion

Thirty Fourth International Conference on Information Systems, Milan 2013 11

Figure 3. Perceived Risk and Perceived Relevance per Website and Item type. The arrows point to the matching item types. Error bars are ± 1 Standard Error.

Regarding perceived Risk, we find that the interaction between Website and Item type is significant (χ2(6) = 246.41, p < .0001). Moreover, for each website, the non-matching item types are perceived as significantly more risky than the matching item type. Also, for each item type, the non-matching websites are perceived as significantly more risky than the matching website13. H3 is thus supported.

Likewise, the interaction between Website and Item type is also significant for Perceived Relevance (χ2(6) = 913.47, p < .0001). For each website, the non-matching item types are perceived as significantly less relevant than the matching item type, and for each item type, the non-matching websites are perceived as significantly less relevant than the matching website. H4 is thus supported as well.

H5+H6. Tool type ! Disclosure

The last row in Table 2 presents the effect of Tool type on Disclosure. Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 6.3% higher for users of the Add tool than for users of the Remove tool, although this effect not significant (p = .631). Surprisingly then, H5 is rejected: there is no significant difference in Disclosure between the Add and Remove tools.

The planned contrast between the traditional Auto tool and the alternative tools is significant (χ2(1) = 4.037, p = .045). Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 24.0% lower for users of the Remove tool compared to users of the Auto tool, a small (d = .165) but significant (p = .047) effect. The odds of Disclosure are 18.9% lower for users of the Add tool compared to users of the Auto tool, a small (d = .107) effect that is not significant (p = .130). H6 is thus partially supported: Disclosure is indeed significantly higher for the Auto tool than for the Remove tool.

Hypotheses 7 and 8

To test H7 and H8, we introduce the interaction between Tool type and Perceived Risk and Relevance (dashed lines) to the path model described in Figure 2. Unfortunately, due to the high correlation between Perceived Risk and Perceived Relevance, we were unable to fit a model that includes both effects. We therefore introduce each effect to the model separately.

H7. Tool type × Perceived Risk ! Disclosure

To model the interaction between Tool type and Perceived Risk, we create a multiple group model, comparing the Add and Remove groups against the Auto group, fixing all parameters except for the intercept and the effect of Perceived Risk. This model again has an excellent fit (χ2(86) = 99.443, p = .152; CFI = .990, TLI = .988; RMSEA = .007, 90% CI: [.000, .013]). 13 To adjust for multiple comparisons, we compared the p-values in Tables 3-5 against Bonferroni-Holm corrected α levels; see http://en.wikipedia.org/wiki/Holm-Bonferroni_method.

80% 85% 90% 95% 100%

Contact info Interests Job skills Health record

" " " -3

-2

-1

0

1

2

3

BlogHeroes I♡WRK Codacare

Perceived risk

# # #

-3

-2

-1

0

1

2

3

BlogHeroes I♡WRK Codacare

Perceived relevance

Counteracting the negative privacy effect of form auto-completion

Thirty Fourth International Conference on Information Systems, Milan 2013 11

Figure 3. Perceived Risk and Perceived Relevance per Website and Item type. The arrows point to the matching item types. Error bars are ± 1 Standard Error.

Regarding perceived Risk, we find that the interaction between Website and Item type is significant (χ2(6) = 246.41, p < .0001). Moreover, for each website, the non-matching item types are perceived as significantly more risky than the matching item type. Also, for each item type, the non-matching websites are perceived as significantly more risky than the matching website13. H3 is thus supported.

Likewise, the interaction between Website and Item type is also significant for Perceived Relevance (χ2(6) = 913.47, p < .0001). For each website, the non-matching item types are perceived as significantly less relevant than the matching item type, and for each item type, the non-matching websites are perceived as significantly less relevant than the matching website. H4 is thus supported as well.

H5+H6. Tool type ! Disclosure

The last row in Table 2 presents the effect of Tool type on Disclosure. Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 6.3% higher for users of the Add tool than for users of the Remove tool, although this effect not significant (p = .631). Surprisingly then, H5 is rejected: there is no significant difference in Disclosure between the Add and Remove tools.

The planned contrast between the traditional Auto tool and the alternative tools is significant (χ2(1) = 4.037, p = .045). Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 24.0% lower for users of the Remove tool compared to users of the Auto tool, a small (d = .165) but significant (p = .047) effect. The odds of Disclosure are 18.9% lower for users of the Add tool compared to users of the Auto tool, a small (d = .107) effect that is not significant (p = .130). H6 is thus partially supported: Disclosure is indeed significantly higher for the Auto tool than for the Remove tool.

Hypotheses 7 and 8

To test H7 and H8, we introduce the interaction between Tool type and Perceived Risk and Relevance (dashed lines) to the path model described in Figure 2. Unfortunately, due to the high correlation between Perceived Risk and Perceived Relevance, we were unable to fit a model that includes both effects. We therefore introduce each effect to the model separately.

H7. Tool type × Perceived Risk ! Disclosure

To model the interaction between Tool type and Perceived Risk, we create a multiple group model, comparing the Add and Remove groups against the Auto group, fixing all parameters except for the intercept and the effect of Perceived Risk. This model again has an excellent fit (χ2(86) = 99.443, p = .152; CFI = .990, TLI = .988; RMSEA = .007, 90% CI: [.000, .013]). 13 To adjust for multiple comparisons, we compared the p-values in Tables 3-5 against Bonferroni-Holm corrected α levels; see http://en.wikipedia.org/wiki/Holm-Bonferroni_method.

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Page 31: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

Website

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Thirty Fourth International Conference on Information Systems, Milan 2013 11

Figure 3. Perceived Risk and Perceived Relevance per Website and Item type. The arrows point to the matching item types. Error bars are ± 1 Standard Error.

Regarding perceived Risk, we find that the interaction between Website and Item type is significant (χ2(6) = 246.41, p < .0001). Moreover, for each website, the non-matching item types are perceived as significantly more risky than the matching item type. Also, for each item type, the non-matching websites are perceived as significantly more risky than the matching website13. H3 is thus supported.

Likewise, the interaction between Website and Item type is also significant for Perceived Relevance (χ2(6) = 913.47, p < .0001). For each website, the non-matching item types are perceived as significantly less relevant than the matching item type, and for each item type, the non-matching websites are perceived as significantly less relevant than the matching website. H4 is thus supported as well.

H5+H6. Tool type ! Disclosure

The last row in Table 2 presents the effect of Tool type on Disclosure. Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 6.3% higher for users of the Add tool than for users of the Remove tool, although this effect not significant (p = .631). Surprisingly then, H5 is rejected: there is no significant difference in Disclosure between the Add and Remove tools.

The planned contrast between the traditional Auto tool and the alternative tools is significant (χ2(1) = 4.037, p = .045). Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 24.0% lower for users of the Remove tool compared to users of the Auto tool, a small (d = .165) but significant (p = .047) effect. The odds of Disclosure are 18.9% lower for users of the Add tool compared to users of the Auto tool, a small (d = .107) effect that is not significant (p = .130). H6 is thus partially supported: Disclosure is indeed significantly higher for the Auto tool than for the Remove tool.

Hypotheses 7 and 8

To test H7 and H8, we introduce the interaction between Tool type and Perceived Risk and Relevance (dashed lines) to the path model described in Figure 2. Unfortunately, due to the high correlation between Perceived Risk and Perceived Relevance, we were unable to fit a model that includes both effects. We therefore introduce each effect to the model separately.

H7. Tool type × Perceived Risk ! Disclosure

To model the interaction between Tool type and Perceived Risk, we create a multiple group model, comparing the Add and Remove groups against the Auto group, fixing all parameters except for the intercept and the effect of Perceived Risk. This model again has an excellent fit (χ2(86) = 99.443, p = .152; CFI = .990, TLI = .988; RMSEA = .007, 90% CI: [.000, .013]). 13 To adjust for multiple comparisons, we compared the p-values in Tables 3-5 against Bonferroni-Holm corrected α levels; see http://en.wikipedia.org/wiki/Holm-Bonferroni_method.

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Counteracting the negative privacy effect of form auto-completion

Thirty Fourth International Conference on Information Systems, Milan 2013 11

Figure 3. Perceived Risk and Perceived Relevance per Website and Item type. The arrows point to the matching item types. Error bars are ± 1 Standard Error.

Regarding perceived Risk, we find that the interaction between Website and Item type is significant (χ2(6) = 246.41, p < .0001). Moreover, for each website, the non-matching item types are perceived as significantly more risky than the matching item type. Also, for each item type, the non-matching websites are perceived as significantly more risky than the matching website13. H3 is thus supported.

Likewise, the interaction between Website and Item type is also significant for Perceived Relevance (χ2(6) = 913.47, p < .0001). For each website, the non-matching item types are perceived as significantly less relevant than the matching item type, and for each item type, the non-matching websites are perceived as significantly less relevant than the matching website. H4 is thus supported as well.

H5+H6. Tool type ! Disclosure

The last row in Table 2 presents the effect of Tool type on Disclosure. Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 6.3% higher for users of the Add tool than for users of the Remove tool, although this effect not significant (p = .631). Surprisingly then, H5 is rejected: there is no significant difference in Disclosure between the Add and Remove tools.

The planned contrast between the traditional Auto tool and the alternative tools is significant (χ2(1) = 4.037, p = .045). Controlling for Perceived Risk, Perceived Relevance, and Item type, the odds of Disclosure are 24.0% lower for users of the Remove tool compared to users of the Auto tool, a small (d = .165) but significant (p = .047) effect. The odds of Disclosure are 18.9% lower for users of the Add tool compared to users of the Auto tool, a small (d = .107) effect that is not significant (p = .130). H6 is thus partially supported: Disclosure is indeed significantly higher for the Auto tool than for the Remove tool.

Hypotheses 7 and 8

To test H7 and H8, we introduce the interaction between Tool type and Perceived Risk and Relevance (dashed lines) to the path model described in Figure 2. Unfortunately, due to the high correlation between Perceived Risk and Perceived Relevance, we were unable to fit a model that includes both effects. We therefore introduce each effect to the model separately.

H7. Tool type × Perceived Risk ! Disclosure

To model the interaction between Tool type and Perceived Risk, we create a multiple group model, comparing the Add and Remove groups against the Auto group, fixing all parameters except for the intercept and the effect of Perceived Risk. This model again has an excellent fit (χ2(86) = 99.443, p = .152; CFI = .990, TLI = .988; RMSEA = .007, 90% CI: [.000, .013]). 13 To adjust for multiple comparisons, we compared the p-values in Tables 3-5 against Bonferroni-Holm corrected α levels; see http://en.wikipedia.org/wiki/Holm-Bonferroni_method.

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Page 32: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

When the type of information requested matches the purpose of the website, people are more likely to disclose it.

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Page 33: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

What causes information disclosure?

perceived risk and relevance

purpose-specificity

Page 34: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

What causes information disclosure?

perceived risk and relevance

purpose-specificity

What is the influence of the auto-completion tool?

Page 35: Counteracting the negative effect of form auto-completion on the privacy calculus

Influence of tool type

We tested three tools: – Auto FormFiller (automatically fills

fields, users can remove manually)  – Remove FormFiller (same but users

can click to remove each field)  – Add FormFiller (no automatic filling,

users can click a button to fill each field)

Please tell us more about yourselfBlogHeroes  will  assign  a  "guild"  to  you  based  on  the  information  you  provide  below.  Note  that  noneof  the  fields  are  required,  but  our  classification  will  be  better  if  you  provide  more  information.

General  info  about  mePlease  provide  some  background  info  to  get  our  matching  process  started.

Name  (first): John (last): Smith

E-­mail  address: [email protected]

Gender: Male

Age  (years): 23

Address: 123 Main St.City: New York State: NY Zip: 12345

What  I  do  for  a  livingSome  guilds  write  about  their  jobs.  Tell  us  more  about  yours,  and  we  can  provide  a  better  match.

Employment  status: Employed for wages

Experience  (years): 5

Current/previous  job: Researcher Sector: Education / training / library

Income  level: between $50K and $100K/year

Education: Doctoral

My  healthSome  guilds  write  about  their  health.  Providing  us  with  some  info  will  help  us  match  them  to  you.

Physical  health: About average

Dietary  restrictions: allergic to nuts

Birth  control  usage: None

> For employers

> For investors

> Contact

> About us

Please  enter  your  informationI WRK will find jobs based on the information you enter on this form.None of the items on the form are required, but if you provide moreinformation the jobs will be a better match.

GENERAL AND CONTACT INFO

General and contact information

FIRST NAME

JohnLAST NAME

Smith clear

AGE

23 clear

GENDER

Male clear

E-MAIL ADDRESS

[email protected] clear

ADDRESS

123 Main St.CITY

New YorkSTATE

NYZIP

12345 clear

WORK EXPERIENCE

Please tell us about your education and work experience, so that wecan find a suitable job for you.

HIGHEST DEGREE EARNED

Doctoral clear

CURRENT EMPLOYMENT STATUS

Employed for wages clear

CURRENT/PREVIOUS JOB

ResearcherSECTOR

Education, library, or training clear

EXPERIENCE (IN YEARS)5 clear

Enter your details, please

Your personal Codacare health insurance policy will be based on theinformation you provide. Please note that none of the items arerequired, but the insurance will be better tailored to your needs if youprovide more information.

General information

Please provide your general information.

Name (first): (last):fill

Address:

fillCity: State: Zip:

Gender:fill

Age:fill

E-‐mail:fill

Health

Please answer the following questions about your health. This is important to find thecorrect care package.

Birth control usage:fill

Weight (lbs):fill

Page 36: Counteracting the negative effect of form auto-completion on the privacy calculus

Influence of tool type

Website

Item type

Disclosure

Risk

Relevance

Tool type

χ2(86) = 99.443, p = .152; CFI = .990, TLI = .988; RMSEA = .007, 90% CI: [.000, .013]

χ2(86) = 95.140, p = .235; CFI = .993, TLI = .992; RMSEA = .006, 90% CI: [.000, .012]

Disclosure

Risk

Relevance

Tool type

Page 37: Counteracting the negative effect of form auto-completion on the privacy calculus

Influence of tool type

!!!!!!!Odds are closest to 1 for the Auto tool, so Risk and Relevance influence Disclosure the least for users of the Auto tool

Auto 0.863***

Remove 0.754***

Add 0.811***

Auto 0.989

Remove 1.133***

Add 1.114***

Disclosure

Risk

Relevance

Tool type

Page 38: Counteracting the negative effect of form auto-completion on the privacy calculus

Influence of tool type

Results:

– Disclosure was not purpose-specific for users of the Auto tool

– Disclosure was purpose-specific for users of the Remove and Add tools. These tools help users consider the website’s purpose in their disclosure decisions

– Additional note: Users of the Add tool were more satisfied, despite having to click more frequently on average!

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Remove

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Page 39: Counteracting the negative effect of form auto-completion on the privacy calculus

But what causes risk and relevance?

What causes information disclosure?

perceived risk and relevance

purpose-specificity

What is the influence of the auto-completion tool?

moderates effect of risk and relevance

Page 40: Counteracting the negative effect of form auto-completion on the privacy calculus

Take-home message

People base their information disclosure decision on the perceived risk and relevance of the information

Perceived risk and relevance (and thus disclosure)

depend on the purpose-specificity of the request

The effect of risk and relevance is moderated by tool type: disclosure is more “calculated” when the add and remove tools are used