Cited by 4Information Retrieval and Search BehaviorCensus and Population EstimationWeb visibility and informetrics

The DOI matches its Crossref record; 28 of the 28 references it cites were found in a registry or an index; 1 of the 21 sources its claims cite were checked for support.

Estimating the Total Volume of Queries to a Search Engine

Open access
Lillo, Fabrizio, Ruggieri, Salvatore·2022·IEEE Transactions on Knowledge and Data Engineering

Abstract

We study the problem of estimating the total number of searches (volume) of queries in a specific domain, which were submitted to a search engine in a given time period. Our statistical model assumes that the distribution of searches follows a Zipf’s law, and that the observed sample volumes are biased accordingly to three possible scenarios. These assumptions are consistent with empirical data, with keyword research practices, and with approximate algorithms used to take counts of query frequencies. A few estimators of the parameters of the distribution are devised and experimented, based on the nature of the empirical/simulated data. For continuous data, we recommend using nonlinear least square regression (NLS) on the top-volume queries, where the bound on the volume is obtained from the well-known Clauset, Shalizi and Newman (CSN) estimation of power-law parameters. For binned data, we propose using a Chi-square minimization approach restricted to the top-volume queries, where the bound is obtained by the binned version of the CSN method. Estimations are then derived for the total number of queries and for the total volume of the population, including statistical error bounds. We apply the methods on the domain ofrecipes and cookingqueries searched in Italian in 2017. The observed volumes of sample queries are collected from Google Trends (continuous data) and SearchVolume (binned data). The estimated total number of queries and total volume are computed for the two cases, and the results are compared and discussed.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

The paper proposes Zipf-law-based estimators for the total number and total volume of queries in a search-engine domain from biased SEO-tool samples, with separate methods for continuous and binned data. Applied to Italian recipe/cooking queries in 2017, it estimates totals from Google Trends and SearchVolume and compares the two.

Key findings

  • Simulations favor nonlinear least squares (NLS) regression for continuous data and Chi-square minimization for binned data; NLS converges for non-uniform and noisy sampling, while sketchy sampling causes overestimation of total volume.
  • For Google Trends continuous data, the paper estimates β = 0.7745 and ĉ = e^17.5189 = 40,584,860, with Δβ = 0.0025 and Δc = 199,263; the NLS fit uses the top max = 1725 queries determined by the CSN method.
  • For SearchVolume binned data, it estimates β = 0.5545 and ĉ = e^14.9551 = 3,125,485, with Δβ = 0.0352 and Δc = 549,134; the Chi-square fit uses the top max = 119 queries determined by Binned-CSN.
  • Table 1 reports, for at least 12 searches/year (monthly average 1), Google Trends Nv = 269,214,520 ± 18,507,467 and Vv = 14,169.58M ± 827.91M, versus SearchVolume Nv = 5,849,311,206 ± 10,205,374,040 and Vv = 157,547.70M ± 262,434.70M; the smaller SearchVolume β implies a larger long tail, with 5.85B queries searched at least once a month versus about 270M for Google Trends.

Methods

  • The model assumes the population rank-volume distribution follows Zipf’s law and models observed-volume bias through non-uniform sampling, noisy sampling, and sketchy sampling; simulations use N = 10^6, c = 10^5, β = 0.7745, n = 1000, p = 0.001, γ = 0.001, and bin ratio δ = 1.2324.
  • Continuous estimation uses CSN for β and NLS regression for c and β on top-volume queries; binned estimation uses Binned-CSN for β and Chi-square minimization for c and β, with a constrained Chi-square variant and a sketchy-optimized restriction to volumes ≥ 10γv1.
  • Empirical data consist of 120K distinct Italian recipe/cooking queries crawled from 18 popular websites and validated by humans; observed volumes for 2017 were collected from Google Trends (about 18.5K queries) and SearchVolume (about 12.5K queries), then used to estimate Nv and Vv with error propagation.

Limitations

  • The paper states that the approach depends on the population being Zipfian and the domain being coherent; it also states that sample construction must include top-volume queries, that the SEO-tool bias scenario is unknown, and that Google Trends has an additional scaling bias from relative to absolute volumes.
  • The paper notes that SearchVolume returned no result for about 6K queries, including 26 of the top 100 Google Trends observed-volume queries, and that correlation between SearchVolume and Google Trends volumes is weak (Kendall’s τ = 0.3717); binned data also produce larger statistical errors than continuous data.
  • Evident from the text: empirical validation is limited to one domain, language, and year, with no ground-truth total volume; simulation conclusions depend on assumed parameters, and the sketchy-optimized method requires knowing γ.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1109/tkde.2021.3054668

Cites

28 of 28 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Figures

Fig. 1 Empirical rank-volume distribution (scaled Google Trends estimates) for the investigated dataset (see Section 7 for details). Best view in color.
Fig. 1 Empirical rank-volume distribution (scaled Google Trends estimates) for the investigated dataset (see Section 7 for details). Best view in color.CC-BY · From the PDF
Fig. 2 Simulation of different samplings from a Zipf's law.
Fig. 2 Simulation of different samplings from a Zipf's law.CC-BY · From the PDF
Fig. 3 Simulations on estimation of c : error bars (mean ± stdev).
Fig. 3 Simulations on estimation of c : error bars (mean ± stdev).CC-BY · From the PDF
Fig. 4 Simulations on estimation of β : error bars (mean ± stdev).
Fig. 4 Simulations on estimation of β : error bars (mean ± stdev).CC-BY · From the PDF
Image 5
CC-BY · From the PDF
Image 6
CC-BY · From the PDF
Fig. 5 Simulations on the estimation of the total volume V : error bars (mean ± stdev).
Fig. 5 Simulations on the estimation of the total volume V : error bars (mean ± stdev).CC-BY · From the PDF
Image 8
CC-BY · From the PDF
Fig. 6 Simulations on estimation of the population size N : error bars (mean ± stdev). Sketchy case in the left plot exceeds the y-axis limits.
Fig. 6 Simulations on estimation of the population size N : error bars (mean ± stdev). Sketchy case in the left plot exceeds the y-axis limits.CC-BY · From the PDF
Image 10
CC-BY · From the PDF
Fig. 7 Estimated volume (Eq. 8) as a function of ˆ β , assuming ˆ c = c . Simulation parameters: N = 10 6 , c = 10 5 , β in title.
Fig. 7 Estimated volume (Eq. 8) as a function of ˆ β , assuming ˆ c = c . Simulation parameters: N = 10 6 , c = 10 5 , β in title.CC-BY · From the PDF
Fig. 8 Scatterplot of empirical vs estimated total volume.
Fig. 8 Scatterplot of empirical vs estimated total volume.CC-BY · From the PDF
Fig. 9 Left: empirical rank-volume distribution (SearchVolume estimates). Right: bins from the empirical distribution.
Fig. 9 Left: empirical rank-volume distribution (SearchVolume estimates). Right: bins from the empirical distribution.CC-BY · From the PDF
Fig. 10 Simulation of binned sampling from a Zipf's law.
Fig. 10 Simulation of binned sampling from a Zipf's law.CC-BY · From the PDF
Fig. 11 Simulations on estimation of c for binned data: error bars (mean ± stdev). The horizontal line is the true value of c .
Fig. 11 Simulations on estimation of c for binned data: error bars (mean ± stdev). The horizontal line is the true value of c .CC-BY · From the PDF
Image 16
CC-BY · From the PDF
Fig. 12 Simulations on estimation of β for binned data: error bars (mean ± stdev). The horizontal line is the true value of β .
Fig. 12 Simulations on estimation of β for binned data: error bars (mean ± stdev). The horizontal line is the true value of β .CC-BY · From the PDF
Image 18
CC-BY · From the PDF
Image 19
CC-BY · From the PDF
Image 20
CC-BY · From the PDF
Image 21
CC-BY · From the PDF
Image 22
CC-BY · From the PDF

Verification

Claims the paper makes

75 Own result · 54 Own interpretation · 9 Not checked yet · 6 No basis given · 3 No full text of the sources · 2 Check pending · 2 Own method · 1 Partly supported · accuracy not yet measured

Verify all 12 references — free account

Show all 96 claims

  • It may state two separate claims as one. 30
  • The quote only partly states this claim. 2
  • Probably not a substantial claim. 27
56 of 56
  • The authors state this as an assumption.

    The distribution of searches follows a Zipf's law.

    “Our statistical model assumes that the distribution of searches follows a Zipf's law”
    “We start from the basic assumption that the rank-volume distribution of the whole population of queries (i.e.observed and unobserved) follows a Zipf's law.”
    “We assume that the distribution of searches follows a Zipf's law”
  • The authors state this as an assumption.

    The observed sample volumes are biased according to three possible scenarios.

    “Our statistical model assumes that the distribution of searches follows a Zipf's law, and that the observed sample volumes are biased accordingly to three possible scenarios.”
  • The authors state this as an assumption.

    The sample of observed volumes is not uniform, but depends on the rank of queries over the population (non-uniform sampling).

    “We are able to model this behavior by assuming that the sample of observed volumes is not uniform, but it depends on the rank of queries over the population (non-uniform sampling).”
  • The authors state this as an assumption.

    The sampling probability decays exponentially with rank (geometric sampling).

    “we consider a geometric sampling p i ∝ p(1 -p) i-1 , i.e., the sampling probability decays exponentially with the rank.”
  • The authors state this as an assumption.

    The smallest volume of a query in the population V_N is known and equals 1.

    “We assume that V N , the smallest volume of a query in the population, is known.This assumption is realistic for absolute frequencies, since V N = 1.”
  • The paper relies on this without support.

    Low-volume queries are monitored with low probability by SEO tools, and for such queries SEO tools return no observed volume.

    “Low volume queries are monitored with low probability by SEO tools.For such queries, SEO tools return no observed volume.”
  • The paper relies on this without support.

    The biases behind observed volumes reported by SEO tools remain unknown.

    “The biases behind observed volumes reported by SEO tools remain unknown.”
  • The paper relies on this without support.

    Most SEO tools do not provide an absolute observed volume of a query, but rather provide an interval estimate of the volume (binned observed volumes).

    “Most SEO tools do not provide an absolute observed volume of a query, but rather they provide an interval estimate of the volume, i.e., binned observed volumes.”
  • The paper relies on this without support.

    Intervals ameliorate the noise introduced in the estimation process.

    “The motivation is that intervals ameliorate for the noise introduced in the estimation process.”
  • The authors state this as an assumption.

    There are M bins, and for j ∈ [1, M], the j-th bin consists of the interval [ℓ_{j-1}, ℓ_j), where ℓ_0 = V_N.

    “We assume that there are M bins, and that for j ∈ [1, M ], the j-th bin consists of the interval [ℓ j-1 , ℓ j ), where ℓ 0 = V N (the smallest volume).”
  • The paper relies on this without support.

    SEO tools typically report as observed volume the upper bound ℓ_j of the bin.

    “SEO tools typically report as observed volume the upper bound ℓ j of the bin.”
  • The authors state this as an assumption.

    The errors ∆β on β and ∆c on c are independent.

    “Using the propagation of errors under the assumption that the errors ∆β on β and ∆c on c are independent, the error on N is:”
  • The authors state this as an assumption.

    The unobserved rank distribution of query volumes in the reference population follows a Zipf's law.

    “By doing the sensible assumption that the unobserved rank distribution of query volumes follows a Zipf's law”
    “This motivated our assumption that the reference population, namely the queries searched in a reference domain, follows a Zipf's law.”
  • The authors state this as an assumption.

    Observed volumes are biased only as modeled in Section 4.

    “It is worth noting that these conclusions hold under the assumption that observed volumes are biased only as modeled in Section 4.”
  • The authors state this as an assumption.

    There is no information on the sampling bias.

    “Assuming no information on the sampling bias”
15 of 15

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

4 of 4

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Metadata

Authors
Lillo, F., & Ruggieri, S.
Affiliations
  • University of Bologna (IT)
  • University of Pisa (IT)
Venue
IEEE Transactions on Knowledge and Data Engineering
Published
2022-11-01
Volume
34
Issue
11
Pages
5351-5363
ISSN
  • 1041-4347 (ISSN-L)
  • 1558-2191
  • 2326-3865
OpenAlex
W3122354058
Cited by
4
References
28
Citations by year
2026: 3 · 2023: 1
FWCI
0.16
Type
journal article
Language
en
Open access
Locations
  • IEEE Transactions on Knowledge and Data Engineering (publishedVersion)
  • arXiv (Cornell University) (submittedVersion, cc-by)
  • Archivio istituzionale della ricerca (Alma Mater Studiorum Università di Bologna) (submittedVersion, other-oa)
  • arXiv (Cornell University) (submittedVersion)
  • CINECA IRIS Institutial research information system (University of Pisa) (submittedVersion, other-oa)
  • Scuola Normale Superiore di Pisa (submittedVersion, other-oa)
  • arXiv (Cornell University) (cc-by)
Funders
ForTop S.R.L.
Topics
  • Physical Sciences › Computer Science › Information Systems › Information Retrieval and Search Behavior
  • Physical Sciences › Mathematics › Statistics and Probability › Census and Population Estimation
  • Physical Sciences › Computer Science › Information Systems › Web visibility and informetrics
Keywords
web search queries, Zipf's law, power-law distribution, sampling bias, nonlinear least squares, chi-square minimization, Google Trends, keyword research, Italian language

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