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The Future of Traditional Telephone Research New Data from the Field | April 2016 [email protected] | 484-840-4300 | [email protected]

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Page 1: The Future of Traditional Telephone Research · 2016-04-14 · 20: Dutwin/Buskirk: Major comparison of three telephone samples, two opt-in panels, and one in-person sample with a

The Future of Traditional Telephone Research

New Data from the Field | April 2016

[email protected] | 484-840-4300 | [email protected]

Page 2: The Future of Traditional Telephone Research · 2016-04-14 · 20: Dutwin/Buskirk: Major comparison of three telephone samples, two opt-in panels, and one in-person sample with a

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Overview

• A Brief Review of Telephone as a Survey Platform: Past and Present– Historical Trends– Trends in Telephone Dispositions, 1970s to Present

• Two Metrics: Quality and Cost– Quality: Comparisons to Opt-In Panels– Quality: Comparison to Present-Day Low Response

Rate Telephone vs. High Response Rate Telephone– Quality: Data Quality in the Future—Cell Phones– Costs: Trend Analysis of Costs in Telephone Surveys

• Conclusions and Q&A

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A Brief History of Telephone Survey Research /

Past-Present Trends

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• The 1980s – 90s: A Golden Age– Computerized listing of “white pages” allows survey

research firms to develop highly efficient RDD frames of all U.S. households (that own a phone).

– Computerization allows for auto-dialing capabilities.

• 2000+: The Age of Chaos!!!!– Response rates begin to decline in the age of

telemarketing as households begin to screen calls via caller ID and Lose That Loving Feeling.

– Households slowly/steadily eschew landlines. – Internet surveys invented…and by the way they are

MUCH cheaper.– TCPA + trail lawyers = Firms interpreting/complying.

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Landline Ownership

0.0%

20.0%

40.0%

60.0%

80.0%

100.0%

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025

Percent of HH Cell Phone Only

Landline has 5-10 years left.

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Declining Response Rates

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Response Rates, 1995 - 2013

ABC

Pew

CBS

BRFSS

SCA

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• AAPOR Task Force on the Future of Telephone Interviewing– Call to firms to provide outcome dispositions for all call attempts on

general population studies, dual-frame, trackers, 2008 – present.

Trends in Telephone Dispositions in the Age of Cell Phones

Data Study Scrub LL Scrub Cell First year

Last year LL Sample Cell Sample

ABC ABC PollsBiz Purge 2010-2015

None 2008 2015 259,677 188,177

Gallup Gallup Daily Tracking Surveys

None None 2009 2015 18,490,017 14,465,292

GfK AP PollsAug 2012 to present

None 2009 2014 434,405 100,586

NBC NBC Polls 2012 2015 125,382 140,384

PSRAI Pew Omnibus Biz Purge None 2010 2015 285,708 165,711

Pew Pew Internet & American Life Polls

Biz Purge None 2007 2015 369,301 185,385

RTI Survey of Consumer Attitudes

None None 2010 2013 197,878 432,149

SRBI Confidential Biz PurgeInactive 2014+

2007 2014 280,880 85,329

SSRS SSRS Omnibus MSG ID+ None 2009 2015 696,688 622,684

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Trends in Dispositions: Refusals and Callbacks

0%

20%

40%

60%

80%

2008 2009 2010 2011 2012 2013 2014 2015

Refusal Rate: Cellphones

0%

20%

40%

60%

80%

2008 2009 2010 2011 2012 2013 2014 2015

Refusal Rate: Landlines

Landlines: 4% increase

Cell Phones: 2% decrease

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Trends in Dispositions: No Answer/Answering Machines

0%

20%

40%

60%

80%

2008 2009 2010 2011 2012 2013 2014 2015

NA/AM Rate: Cellphones0%

20%

40%

60%

80%

2008 2009 2010 2011 2012 2013 2014 2015

NA/AM Rate: Landlines

Landlines: 10% increase(4% since 2009)

Cell Phones: 24% increase(14% since 2010)

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Trends in Dispositions: Non-Working

0%

20%

40%

60%

2008 2009 2010 2011 2012 2013 2014 2015

NW Rate: Cellphones0%

20%

40%

60%

2008 2009 2010 2011 2012 2013 2014 2015

NW Rate: Landlines

Landlines: 12% increase

Cell Phones: 15% decrease(10% since 2009)

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Trends in Dispositions: Yield

-

0.02

0.04

0.06

0.08

0.10

2008 2009 2010 2011 2012 2013 2014 2015

Yield: Cellphones

-

0.02

0.04

0.06

0.08

0.10

0.12

2008 2009 2010 2011 2012 2013 2014 2015

Yield: Landlines

Landlines: decreased yield by a factor of 2.4 (2.0 since 2009)

Cell Phones: decreased yield by a factor of 1.3 (1.15 since 2009)

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Changes in Telephone Survey Demographics

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

2008 2009 2010 2011 2012 2013 2014 2015

Trends in Respondent Age, 2008-2015

Poly. (Landline 18-29)

Poly. (Cellphone18-29)

Poly. (Landline65+)

Poly. (Cellphone65+)

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Changes in Telephone Survey Demographics

Note: Pew Research Center 2014

34% 33%

65%

36% 32%

26%31% 34%

7%

0%

20%

40%

60%

80%

100%

Benchmark Cell Sample LandlineSample

18-34

35-54

55+

Missing

8% 8% 6%

15% 12%6%

12% 12%

8%

66% 66%79%

0%

20%

40%

60%

80%

100%

Benchmark Cell Sample LandlineSample

White Non-Hisp

Black Non-Hisp

Hispanic

Other/Mixed Non-Hisp

Missing

Age Distribution by Sample Race Distribution by Sample

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Data Quality: A Review of Telephone vs. Opt-In

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Lets Be Clear Here…

Many claims have been made regarding whether telephone has “lost steps” in data quality, such that opt-in surveys are just as good.

I don’t agree or disagree. However….

This is an empirical question, embedded in a logical argument:1. High response rate telephone is superior in data quality to

opt-in.2. High response rate telephone is a thing of the past.3. (Research question): Has the loss of response rate

resulted in low data quality? How much lower relative to data quality in opt-in?

…So lets see what the data says….

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How do we compare?

• Direct comparisons• Mean absolute error• Largest absolute error• Number of significant differences• Standard deviation of the absolute biases• Weighted cost per interview (cost per effective

interview)

Callegaro, Mario, Villar, Ana, Yeager, David, and Krosnick, Jon (2014). A critical review of studies investigating the quality of data obtained with online panels based on probability and nonprobability samples. In Online Panel Research: A Data Quality Perspective (M. Callegaro, R. Baker, J. Bethlehem, A. Goritz, J. Krosnick, and P. Lavrakas, eds), pp. 23 – 53.

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ARF Study

• The Advertising Research Foundation (ARF) set up the Online Research Quality Council (ORQC) in August 2007.

• 17 US online panel providers (all using nonprobability samples) a telephone sample panel, and a mail sample panel.

• Factual and behavioral questions were asked with the same question wording as the benchmarks they would be compared against; data weighted.

• Wide variation across panels in the survey estimates.

• Sample tenure effected estimates derived from panels.

Walker, R., Pettit, R., & Rubinson, J. (2009). A special report from the Advertising Research Foundation: The foundations of quality initiative: A five-part immersion into the quality of online research. Journal of Advertising Research, 49, 464–485.

1819

2020

2123

242626

2727

2828

3030

3132

33

0 10 20 30 40

BenchmarkABCDEFGHIJKLMNOPQ

Comparison of Smoking Prevalence; Benchmark vs. 17 Opt-In Panels

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Stanford Studies

• Yeager: Data from one Random Digit Dialing (RDD) telephone survey, one Internet survey of a probability sample recruited by RDD, and seven Internet surveys of non-probability samples were compared against benchmarks.

• Mean absolute error based on dozens of metrics from demographics to drinking habits to ownership of a number of products/household features.

• Bias about 40% worse on opt-in; weighting essentially made no difference.

Yeager, David S., Krosnick, Jon A., Chang, LinChait, Javitz, Harold S., Levendusky, Matthew S., Simpser, Alberto, & Wang, Rui (2011). Comparing the accuracy of RDD telephone surveys and internet surveys conducted with probability and non-probability samples. Public Opinion Quarterly, 75, 709–747.

• Similar results found in other Stanford studies including Malhotra et al (2007) and Chiang et al (2009).

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Weighting Approaches• Given a clear tendency toward bias, alternative approaches have been applied to opt-in in

the attempt to reduce survey error:– Propensity weighting (w/ or w/o webographics)– Calibration– Sample matching

• Success has been quite mixed.*

* See Dever & Shook-Sa, 2015; DiSogra et al., 2015; Peters, 2015; Rivers, 2009; Schonlau, 2007; ZuWallack, 2015.

Scho

nlau

, Van

Soe

st &

Kap

teyn

, 201

5

Phone Web RawWeb

Raked

WebRaked &

Webo

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Dutwin/BuskirkMajor comparison of three telephone samples, two opt-in panels, and one in-person sample with a range of weighting applications tested, across key demographic interactions.

Dutwin, David, and Buskirk, Trent (2016). Apples to Oranges or Gala versus Golden Delicious? Comparing Data Quality of Non-Probability Internet Samples to Low Response Rate Probability Samples. Special 2016 Issue of Public Opinion Quarterly on the Future of Survey Research.

5.9

6.9

3.4

3.5

3.5

2.2

0 2 4 6 8

Panel 1 Unweighted

Panel 2 Unweighted

Telephone 3 Unweighted

Telephone 1 Unweighted

Telephone 2 Unweighted

In Person Unweighted

Overall Average Absolute Biases for Row/Column Percentages by Unweighted Samples

2.2

2.8

3.9

2.7

2.8

2.7

3.9

2.2

1.6

1.5

2.1

0.8

0 1 2 3 4

Panel 1 Raked

Panel 2 Raked

Panel 2 Propensity Weighted

Panel 2 Propensity Weighted…

Panel 2 Matched

Panel 2 Matched and Raked

Panel 1 Matched

Panel 1 Matched and Raked

Telephone 3 Raked

Telephone 1 Raked

Telephone 2 Raked

In Person Weighted

Overall Average Absolute Biases for Row/Column Percentages by Weighted/Matched Samples

1.32.42.52.4

1.11.61.6

1.00.70.8

0.90.2

0 1 2 3

Panel 1 RakedPanel 2 Raked

Panel 2 Propensity WeightedPanel 2 Propensity Weighted…

Panel 2 MatchedPanel 2 Matched and Raked

Panel 1 MatchedPanel 1 Matched and Raked

Telephone 3 RakedTelephone 1 RakedTelephone 2 RakedIn Person Weighted

Average Standard Deviation of Absolute Biases for Weighted Samples

2.712.83

6.355.43

1.181.331.361.21

0 5 10

Panel 1 RakedPanel 2 Raked

Panel 2 Propensity WeightedPanel 2 Propensity Weighted…Panel 1 Matched and Raked

Telephone 3 RakedTelephone 1 RakedTelephone 2 Raked

Unequal Weighting Effects

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Opt-In vs. Telephone: Conclusions

• Researchers should avoid nonprobability online panels when one of the research objectives is to accurately estimate population values.

• The few studies that have disentangled mode of administration from sample source indicate that nonprobability samples are generally less accurate than probability samples.

• There are times when a nonprobability online panel is an appropriate choice.

• Not all research is intended to produce precise estimates of population values, and so there may be survey purposes and topics where the generally lower cost and unique properties of Web data collection are an acceptable alternative to traditional probability-based methods.

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Data Quality: A Review of Telephone Data Quality 1996

- Present

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Research Justification

• Telephone response rates have plummeted over the past 20 years.

• Research conducted 15 years ago (Groves 2006; 2008; Keeter, 2000; 2006) found no significant differences between high response rate surveys and low response rate surveys artificially created from the high response rate studies.

• But since then response rates have dropped further still, so a modern analysis is necessary.

• However: if there are no modern high response rate telephone polls then there is no way to replicate the old method; rather, the only option is to analyze changes in bias on studies that strive to be operationally unchanged over time.

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Data

Sample Name

Mode of Data Collection

Cumulative Sample Size

Response Rate Formula

Notes

The BRFSS Telephone 6,118,156 BRFSS CASRO

Weighted by age by gender, race/ethnicity, education, marital status, tenure, gender by race/ethnicity, age by race/ethnicity, region, and phone ownership (where applicable)

CBS Polls Telephone 61,112 RR1

No data available for 2004, and 2005; Response rates reported are AAPOR RR1. Weighted by age, sex, race, education, region, and phone status (where applicable).

ABC Polls Telephone 130,099 RR3

No data available for 1995, 1996, and 1998; Screened out cellphone respondents not cell phone only; Weighted by age, race/ethnicity, sex, education, and phone status (where applicable).

Pew Polls Telephone 98,535 RR3

No data available until 1999. Weighted by gender by age, gender by education, age by education, region, race/ethnicity, population density, and phone use (where applicable).

The GSS In-Person 32.749 RR3 Occurs only every other year; No post-stratification weighting

The NHIS In-Person 1,244,070 RR3No data available 1995 and 1996; Oversamples Hispanics, thus bias with race more pronounced: Weighted by age by sex by race.

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Dutwin and Buskirk on Telephone Data Quality

• Same interaction analysis of demographics used in Dutwin and Buskirk, 2016.

Dutwin, David, and Buskirk, Trent (2016). Telephone Sample Surveys: Dearly Beloved or Nearly Departed? Trends in Survey Errors in the Age of Declining Response Rates. Special 2016 Issue of Public Opinion Quarterly on the Future of Survey Research.

0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

8.0%

BRFSS CBS Pew ABC GSS NHIS

Mean Absolute Error by Dataset, Unweighted

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

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Dutwin and Buskirk on Telephone Data Quality

• Two statistically significant trends:– 2005 – 2007 increase in telephone bias– 2010 – 2015 decrease in telephone bias– No significant changes in in-person

Dutwin, David, and Buskirk, Trent (2016). Telephone Sample Surveys: Dearly Beloved or Nearly Departed? Trends in Survey Errors in the Age of Declining Response Rates. Special 2016 Issue of Public Opinion Quarterly on the Future of Survey Research.

0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

Average Telephone Average In Person

Mean Absolute Error by Mode, Unweighted

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Dutwin and Buskirk on Telephone Data Quality

• Weighting eliminates all bias trends by year in both telephone and in -person samples

Dutwin, David, and Buskirk, Trent (2016). Telephone Sample Surveys: Dearly Beloved or Nearly Departed? Trends in Survey Errors in the Age of Declining Response Rates. Special 2016 Issue of Public Opinion Quarterly on the Future of Survey Research.

0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

4.0%

Average Telephone Average In Person

Mean Absolute Error by Mode, Weighted

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Dutwin and Buskirk on Telephone Data Quality

• There is no overall relationship between response rates and weighted survey error over time.

Dutwin, David, and Buskirk, Trent (2016). Telephone Sample Surveys: Dearly Beloved or Nearly Departed? Trends in Survey Errors in the Age of Declining Response Rates. Special 2016 Issue of Public Opinion Quarterly on the Future of Survey Research.

4.8%

5.0%

5.2%

5.4%

5.6%

5.8%

6.0%

0%

10%

20%

30%

40%

50%

60%

2008 2009 2010 2011 2012 2013 2014

Dec

line

in B

ias

(Ora

nge)

Cel

l Pho

ne S

hare

(Blu

e)

Cell Phone Share vs. Decline in Bias

0%

5%

10%

15%

20%

25%

30%

35%

0%

1%

2%

3%

4%

Res

pons

e R

ate

Surv

ey E

rror

Error in CBS/NYT/ABC/WP/Pew Polls, Response Rate Overlaid, 1999-2014

Error Response Rates

• The share of cell phone interviewed conducted in a given study explains over 40% of the variance in survey error since 2008.

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Telephone Survey Costs

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The Guterbock Studies

• Telephone survey providers polled about the costs of telephonic research.

• Study completed in 2010, repeated in 2013 and again in 2016.• Factors in variables that impact costs, such as use of dialers,

dialer settings, sample scrubbing, etc.• Key metrics:

– Interviewer Hours per Completion = HPC = hours/completes – HPC = 1/CPH– Screening and Recruiting Hours per Completion = SRHPC– HPC = SRHPC + interview length

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Guterbock 2010 Study

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Guterbock 2013 Study

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Guterbock Cost Trends

0

0.5

1

1.5

2

2.5

3

2010 2013 2015

Analysis of Hours per Completion and Frame Ratio

LL HPC Cell HPC HPC Ratio

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Costs: Opt-In versus Telephone

• Based on a typical 15 minute political opinion poll requiring some projectmanagement, programming, incentives, weighting and estimation (no analysis andreporting which is constant between frames).

Opt-In Telephone Cost RatioCPI $15 $60 4:1Design Effect

2.0 1.3

Effective N on 1,000

500 770

CPEI $30 $78 2.6:1

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Conclusion: What is the Future of Telephone Survey Research?

Costs:

• Landline costs are up, cell phone costs are down, but cell phone surveys are still more expensivethan landline.

• Given that cell phones are the future of telephone surveying, it is encouraging however thatcosts are still going down.

• That said, even with effective sample sizes factored in, opt-in surveys are, and surely always wilbe significantly less expensive/

Quality:

• Telephone errors increased in the early 2000s, but have been in decline since then, likely due tothe discarding of landlines.

• Telephone errors minimally two times less than opt-in.• Variance of errors substantially greater in opt-in surveys compared to telephone.

What does this mean?• Groves noted the importance of “fit for purpose” in research; never has it been more true! In so

far that telephone costs now remain stable, and the quality assessments do as well, AND thereare no major improvements on opt-in, then there will be a role for telephone research well intothe future.

• That said, a change in any of the three variables will impact the future of telephone research.

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contact uswith any questions

@ssrs_solutions | 484-840-4300 | [email protected]