{"id":"79e21a88-ebe2-4f95-92d9-a531a3d3f84a","arxiv_id":"2411.13427","paper_version":1,"verdict":"CONDITIONAL","confidence":"MODERATE","novelty_score":6.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":3,"one_line_summary":"Israel's 2014 ban on non-zero price endings eliminated a small rounding tax but shifted retailers to 90-ending prices, likely raising shopper costs by 0.27 to 0.66 percent of fast-moving consumer goods revenue.","lead":"This paper studies Israel's 2014 ban on prices that do not end in zero, which forced stores to round prices such as 9.99 to 9.90 or 10.00. It finds that the ban removed a tiny rounding tax but pushed retailers toward 90-ending prices, so shoppers may now pay more, not less.","discovery_kind":"extension","skeptic_critique":{"model":"deepseek-v4-flash","headline":"The 0.27%–0.66% cost estimate is a before–after difference in penny digits with no control group; the regulation's exempted price-capped goods provide a natural counterfactual the paper never uses.","rationale":"The reader's CONDITIONAL verdict is appropriate. The single most vulnerable step is causal attribution, not the rounding-tax simulation or the left-digit-bias regression. Even if the left-digit bias parameter is imprecisely estimated (0.11–0.69 across specifications), the cost calculation in Table 3 does not rely on that parameter; it relies entirely on the before–after difference in penny digits. That difference is identified off time-series variation only, with no comparison group. The paper has multiple datasets and rich institutional knowledge, but it never exploits the natural control group created by its own exemption rules. The exempted price-capped goods are mentioned in Section 2 but are not used as a counterfactual. A difference-in-differences against those exempt goods would settle whether the penny-digit rise is actually caused by the ban. If it supports the paper, the estimate may still be affected by the use of 2013 quantity weights, but the direction and rough magnitude would be credible. If it does not, the headline conclusion fails. The paper's own caveats about rounding down and about shoppers' willingness to pay are honest but do not repair the missing counterfactual. Therefore the reader's conditional recommendation stands: accept after the causal magnitude is better supported.","tokens_in":23310,"tokens_out":5542,"duration_ms":63129,"concrete_test":"In the CBS CPI data, classify products into treated (FMCG subject to the ban, excluding goods sold by weight) and control (the 21 price-capped goods and fresh produce and meat sold by weight, which were exempt). For prices below NIS 20, compute average penny digits in 2013 and 2021 by group, with product-store fixed effects and a CPI-inflation adjustment. Run a difference-in-differences: if the control group shows an increase in penny digits similar to the treated group, the Table 3 estimate is not caused by the regulation; if the control group is flat, the causal claim is supported.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim is that the 3.3–8.6 agora increase in average penny digits per price (Table 3) is caused by the 2014 ban and therefore costs shoppers NIS 110–269 million per year. This is identified entirely from a 2013 vs 2021 (or 2012 vs 2021) comparison of average penny digits, with no comparator. Inflation, product mix, COVID-19, payment-method trends, or a gradual industry-wide shift toward 90-ending price points could move average penny digits over eight years without any role for the regulation. The paper's own institutional details supply a natural control group: the regulation explicitly exempts 21 price-capped basic goods and goods sold by weight (fresh produce and meat), whose posted prices were allowed to remain non-0-ending. A difference-in-differences comparing penny digits of exempt vs non-exempt FMCG products would directly test whether the penny-digit rise is attributable to the ban. The paper does not run this or any equivalent control comparison. If exempt goods' penny digits rose by the same amount, the headline 'shoppers pay more because of the regulation' collapses. A secondary issue is that Table 3 multiplies 2021 penny differences by 2013 sales volumes, ignoring demand response and entry and exit; this affects the magnitude, but the causal attribution is the load-bearing step.","agreement_with_reader":"agree"},"referee_report":{"model":"deepseek-v4-flash","summary":"The paper evaluates Israel's 2014 price rounding regulation that outlawed non-0-ending prices, using four datasets: CPI price quotes, Nielsen retail scanner data, a 2013 household expenditure survey, and a large supermarket chain's scanner data. The authors first simulate the pre-regulation 'rounding tax' from cash rounding and estimate it at 0.001%–0.002% of FMCG revenue. They then document that following the ban the share of 90-ending prices rose sharply, increasing the average number of agora (pennies) per price by 3.3–8.6 between 2013 and 2021, which they multiply by 2013 sales volumes to obtain an 'inattention penalty' of NIS 111–269 million per year (0.27%–0.66% of FMCG revenue). The paper concludes that the regulation backfired: shoppers pay more, not less.","tokens_in":23550,"tokens_out":4027,"duration_ms":41856,"significance":"If the causal interpretation is correct, the paper provides a striking, policy-relevant unintended consequence of price-ending regulation, with a concrete monetary magnitude and a natural link to the left-digit bias literature. The paper is transparent about its data sources and simulation procedures, and it includes several robustness checks (2012 baseline, all prices, two-week price-duration restriction, and an appendix test of whether 90-endings arise from rounding up rather than down). The headline cost estimate is a direct accounting of observed price-ending changes rather than a prediction from an estimated model, which is a strength. However, the causal claim that the penny-digit increase is attributable to the regulation rests entirely on a before-after comparison with no control group; the paper's own institutional setting offers exempted product categories that could serve as a natural comparator but are not used. The left-digit bias estimates are unstable across specifications and are reported without standard errors.","major_comments":[{"comment":"The central claim that the 3.3–8.6 agora increase in average penny digits between 2013 and 2021 is caused by the 2014 price rounding regulation is identified solely from a before-after difference with no control group; inflation, changes in product mix, payment-method trends, or a gradual industry shift in price-point conventions could move average penny digits over eight years absent any role for the ban. The paper itself notes in footnote 8 that the regulation exempts 21 price-capped basic goods and goods sold by weight such as fresh produce and meat, whose non-0-ending prices remained legal; a difference-in-differences comparison of penny-digit changes between exempt and non-exempt FMCG products would directly test the causal attribution, but the paper does not run this or any equivalent control comparison.","section":"Section 6, Table 3"},{"comment":"The cost estimate multiplies the 2021-vs-2013 penny-digit difference by 2013 sales volumes, ignoring any demand response to higher prices, entry and exit of products, and changes in the composition of products sold over the eight-year horizon; this affects the magnitude of the NIS 111–269 million estimate, and the authors should at least report robustness to using 2021 sales volumes or contemporaneous quantities.","section":"Section 6, Table 3 and Appendix C"},{"comment":"The left-digit bias estimates are not accompanied by standard errors and are highly specification-dependent: theta-hat is 0.22 in the main sample, 0.30 for prices below NIS 10, 0.69 in the alternative identification, and 0.11 when the sample ends in December 2019; these estimates do not support the text's conclusion that the authors have confirmed a left-digit bias of about 0.2, and the instability weakens the interpretation that the regulation encouraged retailers to exploit inattention to a greater extent.","section":"Section 6, Table 2"}],"minor_comments":[{"comment":"The rounding tax simulation assumes that basket sizes and price endings are independent within store type, but the paper does not state this assumption explicitly; the household expenditure survey and CPI data could at least be used to assess the sensitivity of the rounding tax estimate to this independence assumption.","section":"Section 5, Table 1"},{"comment":"The text and figure notes mix '90–99 ending prices' (pre-2014) with '90-ending prices' (post-2014); please clarify that the series after 2014 is the share of exactly 90-ending prices, and make the figure legend consistent.","section":"Section 6, Figure 2"},{"comment":"The paper acknowledges in the final caveat that if shoppers strongly oppose 9-ending prices, the regulation might still make them better off even if they pay a few pennies more; this caveat is important enough to be mentioned in the abstract, which currently states unambiguously that 'shoppers end up paying more, not less.'","section":"Section 7, caveat"},{"comment":"There is a typo in the appendix: 'the likelihood that a “spurious” price change would last more than 1 week is mute' should read 'moot.'","section":"Appendix A"}],"recommendation":"major_revision","confidential_remarks":"The paper's policy conclusion hinges entirely on a causal attribution that is not currently identified. Given that the authors clearly know the institutional details, the absence of any use of the exempted product categories as a control group is the single biggest weakness. I would encourage the editor to request a difference-in-differences design or a credible alternative control comparison before publication; without it, the headline 'shoppers pay more' claim is not supported. The paper is otherwise transparent and well-written, and the topic is a good fit for the journal."},"author_rebuttal":null,"desk_editor":{"model":"deepseek-v4-flash","letter":"Short version: this is a useful descriptive accounting of a real policy change, and the rounding-tax estimate is careful, but the headline claim that the 2014 ban made shoppers pay 0.27-0.66% more is a before-after difference in price-ending digits with no control group. The paper even describes an obvious control group (exempted price-capped goods and goods sold by weight) and then doesn't use it.\n\nWhat's new: the quantitative welfare accounting. Ater & Gerlitz and Strulov-Shlain already showed the shift to 90-endings and the left-digit bias. The contribution here is combining four datasets to size the rounding tax (tiny) and the inattention penalty (much larger). That's worth having.\n\nWhat's good: the simulation for the rounding tax is transparent and uses actual basket-size and price-ending distributions, which is better than Lombra-style guesses. The paper is honest about the direction of rounding (down vs up) and tests it. It also flags the welfare caveat that consumers might value the prohibition of 9-endings even if they pay more.\n\nSoft spots, in order of severity. First, the central cost estimate is identified from a 2013-vs-2021 change in average agora per price, with no comparator. Inflation, product mix, COVID-19, payment-method trends, or a general drift toward 90-endings could move that number. The regulation's exemptions (21 price-capped basic goods and weight-sold items) are a natural comparison group; the paper mentions them in a footnote but never uses them. That's the missing test. Second, Table 3 multiplies 2021 penny differences by 2013 sales volumes, so it ignores any quantity response to higher prices and any entry/exit. That affects magnitude, not attribution, but it should be fixed. Third, the left-digit bias estimates are noisy and specification-dependent (theta from 0.11 to 0.69), with no standard errors; they're used for interpretation, so this is uncomfortable but not load-bearing. The rounding-tax simulation relies on a crude 25% cash share and independence of basket size and price endings, but since the estimated tax is so tiny, these choices don't matter much for the conclusion.\n\nBottom line: the descriptive facts are credible and the policy question is interesting, but the 'shoppers pay more because of the regulation' claim is not established at the stated magnitudes. I'd send this to a serious referee, with the expectation that the causal magnitude gets reworked—ideally with a diff-in-diff using the exempt goods, and with time trends and volume weights handled properly. Not a desk reject, but not a publish-as-is either.","headline":"The paper's clean descriptive accounting of Israel's price-rounding ban is undercut by a headline welfare cost that rests on a before-after comparison with no control group.","tokens_in":24136,"tokens_out":3326,"would_cite":true,"duration_ms":32989,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"deepseek-v4-flash","headline":"This paper argues that Israel's 2014 ban on non-zero-ending prices backfired: it eliminated a negligible rounding tax but let retailers shift to 90-ending prices, so shoppers pay more overall.","keywords":["price rounding regulation","rounding tax","inattention penalty","left-digit bias","9-ending prices","just-below prices","90-ending prices","Israel"],"falsifier":"Compare the penny-digit trends of regulated FMCG items with exempt products in the same stores after 2014; if exempt items such as fresh produce sold by weight or price-capped goods show the same increase in average pennies, the attribution to the regulation is falsified.","tokens_in":23072,"feed_emoji":"🛒","tokens_out":10633,"duration_ms":94056,"temperature":0.7,"pith_summary":"The paper studies Israel's January 2014 regulation that outlawed all non-zero-ending prices, a rule intended to eliminate the rounding tax on cash bills and to stop retailers from using 9-ending just-below prices. Using four datasets on fast-moving consumer goods, it finds the rounding tax had been tiny, about 0.001% to 0.002% of market revenue, while the regulation itself created a much larger cost. Retailers responded by making 90-ending prices the new just-below price, raising the average number of pennies per price; by 2021 shoppers were paying an estimated NIS 269 million (0.66% of FMCG revenue) more than in 2013, or NIS 111 million (0.27%) more than in 2012. The paper's bottom line is that the regulation made shoppers pay more, not less, and that policies should be judged by results rather than intentions.","feed_headline":"Shoppers paid more after Israel banned odd price endings","feed_subtitle":"Retailers switched to .90 endings, costing shoppers up to 0.66% of grocery market revenue.","key_machinery":"The load-bearing object is the left-digit bias parameter $\\theta$ from the perceived-price model $\\hat p = (1-\\theta)p + \\theta(\\Delta + \\lfloor p \\rfloor)$, where $\\lfloor p \\rfloor$ is the price's integer part and $\\Delta$ is the focal ending. The paper estimates $\\theta$ from the natural experiment created by the regulation: for products whose 2013 modal price was 99-ending, the ban forced some prices to NIS 0.01 above that modal price (a 00-ending) and others NIS 0.09 below (a 90-ending); the demand gap between these two outcomes, beyond what the price elasticity predicts, identifies $\\theta \\approx 0.22$ in the main sample. This parameter carries the argument because it explains why retailers can raise penny digits without losing sales. The rounding-tax side is carried by Monte Carlo simulations that combine the store-level distribution of price endings with the basket-size distribution from the household survey, following the standard method of simulating 10,000 cash transactions per store type.","core_discovery":"The paper's central claim is that Israel's 2014 price rounding regulation, which outlawed all non-zero-ending prices, achieved its first goal but failed its second and made shoppers worse off overall. Using consumer-price-index price data, retail scanner data, a household expenditure survey, and one large retailer's scanner data, the authors estimate that the pre-regulation rounding tax was negligible, about NIS 507,000 in 2013, or 0.001% to 0.002% of FMCG revenue. They then show that retailers responded to the ban by making 90-ending prices the dominant ending; by 2021, 90-ending prices made up 71.8% of prices in supermarkets and drugstores, 57.0% in small grocery stores, and 42.0% in convenience stores. Because shoppers process prices left-to-right and underweight the rightmost digits, these 90-ending prices act as just-below prices, allowing retailers to raise the average number of pennies per price by 3.3 to 8.6 agora depending on store type. The paper estimates the resulting inattention penalty at NIS 269 million in 2021 relative to 2013 (0.66% of FMCG revenue), or NIS 111 million relative to 2012 (0.27%), concluding that the regulation's cost to shoppers exceeds the rounding tax it eliminated.","pith_inferences":["A natural causal test would compare penny-digit trends in regulated products with exempt categories in the same stores, such as fresh produce sold by weight or price-capped goods; if exempt items show a similar rise in average pennies, the regulation is not the cause.","The welfare verdict could still favor the regulation if shoppers' documented aversion to 9-ending prices translates into a real willingness to pay for their abolition, a quantity the paper leaves unmeasured.","The same mechanism may apply wherever rounding rules are adopted: retailers may migrate to the highest permitted ending, converting an intended consumer protection into a price-level increase.","Recomputing the cost with 2021 rather than 2013 sales weights, or separating the pandemic years, would show how much of the 0.27% to 0.66% range depends on the before-after design."],"forward_implications":["The pre-2014 rounding tax was so small, 0.001% to 0.002% of FMCG revenue, that eliminating low-denomination coins was not, by itself, a meaningful consumer cost.","Banning non-zero endings did not remove psychological price points: 90-ending prices became the new just-below price, with 2021 shares reaching 71.8%, 57.0%, and 42.0% across the three store types.","The regulation raised the average number of pennies per price by 3.3 to 8.6 agora depending on store type, adding an estimated NIS 269 million (0.66%) to shoppers' annual FMCG spending relative to 2013.","Because the penny-digit increase applies to every item and to both cash and card payments, while the rounding tax applied only to cash bills, the post-regulation cost far outweighs the eliminated tax.","A coarser allowed price grid of only ten endings makes small price changes less likely, which may increase price rigidity and reduce market efficiency."],"supporting_citations":[{"why":"Defines the rounding tax and supplies the coin-elimination framework that the paper's simulation builds on.","marker":"Lombra (2001)"},{"why":"Provides the alternative small-estimate method and the transaction-level basket assumptions used for comparison.","marker":"Chande and Fisher (2003)"},{"why":"Adds the sales-tax-adjusted rounding tax estimates that the paper benchmarks against.","marker":"Whaples (2007)"},{"why":"Documents the left-digit effect in price cognition that underlies the inattention penalty.","marker":"Thomas and Morwitz (2005)"},{"why":"Supplies the left-digit bias model, the US bias estimate of about 0.2, and the demand estimation approach the paper adapts.","marker":"Strulov-Shlain (2023)"},{"why":"Shows Israeli shoppers also perceive 90-endings as low and provides the reform-based identification strategy used here.","marker":"Strulov-Shlain (2021)"},{"why":"Shows Israeli shoppers learned to associate 90-endings with low prices after the regulation, supporting the new just-below price claim.","marker":"Snir et al. (2017)"},{"why":"Documents how outlawing odd prices affects price endings and rigidity, the setting this paper extends.","marker":"Ater and Gerlitz (2017)"}],"fun_headline_variants":["Israel's price-ending ban backfired on shoppers","Price rounding law made Israelis pay more","Odd price ban cost shoppers 269M shekels","Retailers' .90 endings beat Israel's price law"],"cache_read_input_tokens":3200,"weakest_assumption_plain":"The calculation that shoppers pay more rests on the assumption that the 2013-to-2021 rise in the average number of pennies per price was caused by the rounding regulation, rather than by inflation, product mix changes, the pandemic, or payment trends.","fun_headline_variants_meta":{"raw":{"variants":["Israel's price-ending ban backfired on shoppers","Price rounding law made Israelis pay more","Odd price ban cost shoppers 269M shekels","Retailers' .90 endings beat Israel's price law"]},"model":"deepseek-v4-flash","effort":"low","cost_usd":0.000507,"raw_usage":{"total_tokens":2501,"prompt_tokens":1007,"completion_tokens":1494,"prompt_tokens_details":{"cached_tokens":384},"prompt_cache_hit_tokens":384,"prompt_cache_miss_tokens":623,"completion_tokens_details":{"reasoning_tokens":1431}},"tokens_in":623,"tokens_out":1494,"duration_ms":13314,"temperature":1.0,"reasoning_tokens":1431,"cache_read_input_tokens":384,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-08-12T16:25:15.152022+00:00","model_set":{"reader":"deepseek-v4-flash"},"falsifier":"Compare the penny-digit trends of regulated FMCG items with exempt products in the same stores after 2014; if exempt items such as fresh produce sold by weight or price-capped goods show the same increase in average pennies, the attribution to the regulation is falsified.","supporting_citations":[],"review_version":1}