The DOI matches its Crossref record; none of the 11 sources its claims cite is checked for support yet.
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Written from the paper’s full text.
TL;DR
The authors defend their survey-based estimate that the 1+ listed telephone frame covers about 95% of residential landline households against criticism that their denominator estimate of 87.1 million landlines was too low. They argue their proportion estimates are valid regardless of the absolute count and present evidence that their total landline estimates align reasonably with FCC data.
Key findings
- Estimated 87.1 million residential voice landlines in their survey, compared to a FCC-based estimate of 92.9 million and Fahimi's estimate of 111.7 million.
- Found 2.4% of households have multiple voice landlines (contradicting Fahimi's figure of approximately 7%).
- The 1+ listed banking frame covers approximately 95% of residential landlines when stratified analysis is applied.
- Identified underestimation due to 13.3% of households categorized as "cell phone mostly" who less frequently answer their landlines and may be underrepresented in their resolved sample.
Methods
- Conducted interviewer-administered screening of sampled telephone numbers to classify them as residential voice lines and identified the proportion in each stratum.
- Applied stratum-specific residential proportions to the universe of telephone banks and numbers in each stratum to project totals.
- Validated results against FCC data on residential switched access lines from 2007.
Limitations
- Authors note their estimate of total landlines may be lower than FCC figures partly because "cell phone mostly" households are less likely to answer landlines and thus underrepresented in interviewer-resolved cases (stated in paper).
- The assumption that unresolved cases share the same residential rate as resolved cases may be incorrect, potentially biasing household counts (stated in paper).
- Original publication length restrictions prevented detailed documentation of methods and other study objectives (stated in paper).
Model-written summary. Check it against the paper before relying on it.
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Claims the paper makes
0 of 11 cited sources checked · 0 supported · 0 flagged
- Findingown data§ critical problem
In our study, actual residential multiple landlines for voice was about 2.4%.
“Actual residential multiple landlines for voice was about 2.4% in our study.”
- Also stated in: § secondary issues · plain
“since only 2.4% of households with landlines have more than one voice landline”
Quote in the paperSubstantial claim - Also stated in: § secondary issues · plain
- Findingreasoning§ critical problem
The proportion of residential voice landlines in the 1+ listed banks is 95%.
“we could calculate the proportion (95%) from the 1+ listed banks.”
Quote in the paperSubstantial claim - Findingown data§ secondary issues
Database matching yielded a lower incidence of residential lines for unresolved cases than resulted from using a simple allocation based on resolved cases.
“We found that the database matching yielded a lower incidence of residential lines for the unresolved cases than resulted from using a simple allocation based on the resolved cases.”
Quote in the paperNot a substantial claim - Findingown data§ secondary issues
In our analysis, the non-Telcordia stratum included less than 1% of eligible residence lines.
“Nevertheless, we included this stratum in our analysis (labeled non-Telcordia), and found that it included less than 1% of eligible residence lines.”
Quote in the paperNot a substantial claim - Interpretationreasoning§ critical problem
The FCC-based estimate of 92.9 million residential voice landlines falls in the same range as the earlier estimate of 92 million.
“This falls in the same range of our earlier estimate of 92 million residential voice landlines.”
Quote in the paperNot a substantial claim
- Interpretationreasoning§ critical problem
After subtracting 966,701 for US Territories and Protectorates, there are 92,907,333 residential access lines, including households with multiple landline numbers.
“When you subtract 966,701 for US Territories and Protectorates (counts withheld for CLECs but probably insignificant since suppressed), this translates to 92,907,333 Residential access lines, including households with multiple landline numbers.”
Quote in the paperSubstantial claim - Interpretationreasoning§ critical problem
The number of residential voice landlines in the United States today is probably about 92 million.
“So, we would project that the number of residential voice landlines in the United States, today, is probably about 92 million (112.4 × 0.80 × 1.024) rather than the 97.1 million estimated by Fahimi.”
Quote in the paperNot a substantial claim - Interpretationreasoning§ critical problem
There will be bias against cell phone mostly households in the interviewer resolved numbers because they are less likely or unlikely to answer their landlines.
“Since the cell phone mostly households are less likely or unlikely to answer their landlines, we would anticipate that there will be bias against cell phone mostly households in the interviewer resolved numbers, although they are certainly in the sampling frame.”
Quote in the paperSubstantial claim - Premisecitation§ critical problem
NCHS estimates that 13.3% of households are cell phone mostly, having received all or almost all calls on wireless telephones despite having a landline telephone in the home.
“the NCHS estimates that there are another 13.3% of households who are cell phone mostly, having received all or almost all calls on wireless telephones despite having a landline telephone in the home.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites NCHS
- Premisecitation§ critical problem
Approximately 2.5% of U.S. households have no telephones.
“approximately 2.5% of these households have no telephones”
Quote in the paperSubstantial claim0 of 1 sources checked- cites Fahimi
- Premisecitation§ critical problem
The Brock-Roth paper cited by Fahimi was based on 1999 NHES data.
“It is also important to note that the Brock-Roth paper cited by Fahimi was based on 1999 NHES data.”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites Brock-Roth
- Interpretationreasoning§ critical problem
The survey estimate of 87.1 million residential voice landlines is not dramatically different from the FCC-based estimate of 92.9 million.
“Although we believe that the survey estimate of 87.1 million residential voice landlines is not dramatically different than the FCC based estimate of 92.9 million, it is worth considering why the survey estimate might be lower.”
Quote in the paperNot a substantial claim - Interpretationreasoning§ critical problem
The current rate of multiple landlines used for voice is much smaller than estimated by Fahimi.
“However, we believe the current rate of multiple landlines used for voice is much smaller than estimated by Fahimi.”
Quote in the paperSubstantial claim - Premisecitation§ critical problem
In the Brock-Roth study, the proportion of households with more than one residential landline number was approximately 4%.
“So, the proportion of households with more than one residential landline number appears to have been approximately four percent in that study.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites Brock-Roth
- Premisecitation§ critical problem
There are approximately 112.4 million households in the United States.
“We accept Fahimi's estimates that there are approximately 112.4 million households in the United States”
Quote in the paperSubstantial claim0 of 1 sources checked- cites Fahimi
- Interpretationreasoning§ critical problem
The number of households in the U.S. with residential voice landlines is approximately 89.9 million.
“Hence, the number of households in the U.S. with residential voice landlines would be approximately 89.9 million (112.4 × 0.80).”
Quote in the paperSubstantial claim - Premisecitation§ critical problem
Approximately 17.5% of U.S. households have cell phones only.
“another 17.5% of these households have cell phones only”
Quote in the paperSubstantial claim0 of 1 sources checked- cites Fahimi
- Study design and conductreasoning§ critical problem
The approach outlined in the paper provides an unbiased estimate of the proportion of residential voice landlines in listed and unlisted banks.
“We believe the approach we have outlined in our paper provides for an unbiased estimate of the proportion of residential voice landlines in listed and unlisted banks.”
Quote in the paperSubstantial claim - Interpretationreasoning§ secondary issues
The non-Telcordia stratum represents no impact on the study conclusion because it is already included in the total 5% estimated non-coverage of residential voice landlines for 1+ block samples.
“Most importantly, it represents no impact on the study conclusion because it is already included in the total 5% estimated non-coverage of residential voice landlines for 1+ block samples.”
Quote in the paperNot a substantial claim - Premisecitation§ critical problem
In their AAPOR presentation, Fahimi and colleagues applied their estimated residential rate to the population of their three strata to yield residential estimates of 16,151,285 in the zero listed, 89,902,643 in the 1+ listed, and 5,615,877 in the remaining POTS.
“However, in their AAPOR presentation they applied their estimated residential rate from their survey to the population of their three strata to yield residential estimates of 16,151,285 in the zero listed, 89,902,643 in the 1+ listed, and 5,615,877 in the remaining POTS.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites AAPOR presentation
- Interpretationreasoning§ critical problem
If the assumption of equal hit rate is incorrect, it would affect the total number of estimated households in individual strata and total.
“Although this approach is fine for generating estimates of proportions, if the assumption is incorrect it would affect the total number of estimated households in the individual strata and total.”
Quote in the paperSubstantial claim- The authors state this as an assumption: The residential hit rate in resolved cases is the same as in unresolved cases.
- Interpretationreasoning§ critical problem
If the undetermined cases were allocated, the Fahimi estimate for total residential voice landline would be even larger.
“If they were allocated then the Fahimi estimate for total residential voice landline would be even larger.”
Quote in the paperNot a substantial claim - Interpretationreasoning§ critical problem
The Fahimi study yields a total count of 111.7 million residential landline numbers.
“Hence, while we believe the total number of residential landline numbers should be about 92.9 million, the Fahmi study yields a total count of 111.7 million residential landline numbers.”
Quote in the paperSubstantial claim - Interpretationreasoning§ critical problem
The bias from cell phone mostly cases should have no impact on estimates of proportion by stratum since there is no reason to assume a differential effect by stratum.
“While this may account for some of the difference between our estimated 87.1 million residential voice landlines and an estimated 92.9 million from the FCC figures, it should have no impact on our estimates of proportion by stratum since there is no reason to assume a differential effect by stratum.”
Quote in the paperNot a substantial claim- Rests on an assumption: The residential hit rate does not behave differently by strata.
- Interpretationnone given§ critical problem
Using reciprocal weights to estimate proportions would have produced the same results without the controversy.
“we acknowledge that the use of reciprocal weights to estimate proportions would have produced the same results without the controversy.”
Quote in the paperNot a substantial claim
- It may state two separate claims as one. 10
- Probably not a substantial claim. 3
It may state two separate claims as one.
Findingown data§ critical problemIn our study, 14.7% of households reported more than one phone, most of which were wireless numbers.
“In our study, while we found that 14.7% of households reported more than one phone, most of these were reported as wireless numbers.”
Quote in the paperSubstantial claimProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
Premisecitation§ critical problemThe FCC Report 'Local Telephone Competition: Status as of December 31, 2007' provides 129.7 million incumbent LEC switched access lines, 28.7 million CLEC switched access lines, and 158.4 million total switched access lines.
“For example, the FCC Report”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites FCC Report
It may state two separate claims as one.
Premisecitation§ critical problemIn the Brock-Roth paper, 7% of households had multiple telephone numbers, but only 59% of those households had additional residential landline numbers.
“Although Fahimi correctly cites 7% of households as having multiple telephone numbers in the Brock-Roth paper, he fails to mention that only 59% of those households had additional residential landline numbers (see Table 1 in that paper).”
Quote in the paperSubstantial claim0 of 1 sources checked- cites Brock-Roth
It may state two separate claims as one.
Interpretationcitation§ critical problemThe FCC estimates that 59% of lines are provided to residential customers, yielding 93,477,687 residential switched access lines (83% of all households).
“The FCC also estimates the Percentage of Lines Provided to Residential Customers=59%, yielding the result 158,436,758*0.59=93,477,687residential switched access lines (83% of all households).”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites FCC
It may state two separate claims as one.
Premisereasoning§ critical problemThe number of residential landlines is larger than the number of residential households because some households have more than one landline used for voice.
“We also agree that the number of residential landlines will be larger than the number of residential households as a result of those households with more than one landline used for voice.”
Quote in the paperSubstantial claimIt may state two separate claims as one.
Interpretationown data§ secondary issuesThe distinction between households and residential landlines is less critical to our estimates because only 2.4% of households with landlines have more than one voice landline.
“As noted above, while the distinction between households and residential landlines is absolutely valid as a unit of measure, since only 2.4% of households with landlines have more than one voice landline, the difference is less critical than it might otherwise be to our estimates.”
Quote in the paperSubstantial claimIt may state two separate claims as one.
Interpretationreasoning§ critical problemThe apples-to-apples comparison of projected number of residential voice landlines is 87.1 million in our study and 111.7 million in the Fahimi study, compared to an FCC-based estimate of 92.9 million.
“So, the apples to apples comparison of the projected number of residential voice landlines for the two studies is 87.1 million in our study and 111.7 million in the Fahimi study, compared to an FCC based estimate of 92.9 million.”
Quote in the paperSubstantial claimIt may state two separate claims as one.
Interpretationown data§ secondary issuesThe allocation was chosen because it was based on superior information from interviewer resolved cases and provided a higher (more conservative) allocation of residential lines to unlisted segments.
“We chose the allocation because we felt it was based on the superior information gained from the interviewer resolved cases and also provided a higher (more conservative) allocation of residential lines to the unlisted segments.”
Quote in the paperSubstantial claimIt may state two separate claims as one.
Interpretationreasoning§ critical problemIf a disproportionate amount of cell phone mostly cases cannot be interviewer resolved because they never answer their landline, then the household rate would be higher in unresolved compared to resolved cases, yielding an underestimate of the total number of residential voice landlines.
“If a disproportionate amount of cell phone mostly cases cannot be interviewer resolved because they never answer their landline, then the household rate would be higher in the unresolved compared to resolved cases, yielding an underestimate of the total number of residential voice landlines.”
Quote in the paperSubstantial claim- The authors state this as an assumption: The residential hit rate in resolved cases is the same as in unresolved cases.
Probably not a substantial claim. The paper may give no reason why it holds.
Interpretationreasoning§ critical problemEven if the true household rate is lower or higher in unresolved cases, the result is unbiased so long as it does not behave differently by strata.
“Even if the true household rate is actually lower or higher in the unresolved cases, the result is unbiased so long as it does not behave differently by strata.”
Quote in the paperNot a substantial claim- The authors state this as an assumption: The residential hit rate in resolved cases is the same as in unresolved cases.
- Rests on an assumption: The residential hit rate does not behave differently by strata.
Probably not a substantial claim. The paper may give no reason why it holds.
Interpretationreasoning§ critical problemThe assumption that the residential hit rate in resolved cases is the same for unresolved cases is reasonable for generating an unbiased estimate across strata.
“We believe that -in the absence of evidence to the contrary -this is a reasonable approach to generating an unbiased estimate across strata.”
Quote in the paperNot a substantial claim- The authors state this as an assumption: The residential hit rate in resolved cases is the same as in unresolved cases.
It may state two separate claims as one.
Premisecitation§ critical problemFahimi leaves 4.0% of zero-listed numbers, 2.1% of 1+ listed numbers, and 3.7% of remaining POTS as undetermined, effectively treating these cases as non-residential for the estimates.
“In addition, Fahimi leaves 4.0% of zero-listed numbers, 2.1% of 1+ listed numbers, and 3.7% of remaining POTS as undetermined, so instead of allocating these numbers between residential and non-residential these cases are effectively treated as non-residential for the estimates.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites Fahimi
The authors state this as an assumption.
The residential hit rate in resolved cases is the same as in unresolved cases.
“we assume the residential hit rate in resolved cases would be the same for unresolved cases.”
The paper relies on this without support.
The residential hit rate does not behave differently by strata.
“Even if the true household rate is actually lower or higher in the unresolved cases, the result is unbiased so long as it does not behave differently by strata.”
“since there is no reason to assume a differential effect by stratum.”
Citations
Metadata
- Authors
- Boyle, J., Weiss, A., Bucuvalas, M., & Piekarski, L.
- Affiliations
- Schulman, Ronca & Bucuvalas (US)
- Survey Sampling Inc.
- ORCID
- Boyle, John
- Venue
- Survey Practice
- Publisher
- Survey Practice
- Published
- 2009-01-01
- Volume
- 2
- Issue
- 1
- Pages
- 1-5
- ISSN
- 2168-0094 (ISSN-L)
- OpenAlex
- W1480404197
- Cited by
- 0
- References
- 0
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Survey Practice (publishedVersion)
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