# RECORD de48aa9a311d709ef0a33453d7042001c2e721a6 # TITLE: Public transport, noise complaints, and housing: Evidence from sentiment analysis in Singapore # YEAR: 2021.0 VENUE: Journal of Regional Science DOI: 10.1111/jors.12524 # AUTHORS: Yi Fan; Ho-Pin Teo; Wayne Xinwei Wan # PAGES: 27 CANDIDATE TABLE PAGES (1-based): [12, 14, 15, 19, 20, 21] # ABSTRACT: This paper investigates the effect of a new bus route on noise complaints of residents and the influence of noise on housing price. To overcome the challenge of mapping noise data with subjective emotion, we use a novel data source — text ‐ based noise complaint records from residents in a town in Singapore — and apply natural language processing tools to conduct sentiment analysis. To address the endogeneity concern regarding the bus route, we use a hypothetical least cost path as an instrument for the existing bus route. We find that living closer to the bus route for every 100 m increases noise complaints by around 10 percentage points, and the effect is more severe on medium floor levels (5th – 8th floors) and near bus stops (within 100 m). We further link noise with housing price and discover a price reduction of 3% with a 1 ‐ scale ‐ point increase in noise complaints. This implies that bus noise offsets 17.8% of the benefit from convenience, which sheds light on the importance of noise insulation in transit ‐ oriented developments. propose a novel methodology to measure the quasi real ‐ time noise sentiment at finer detailed level using the noise complaints data, which naturally exists with the ===== PAGE 1 (score 10, numeric-paren 0, table-words 0, var-words 10) ===== J Regional Sci. 2021;61:570–596. 570 | wileyonlinelibrary.com/journal/jors Received: 22 January 2020 | Revised: 25 November 2020 | Accepted: 19 December 2020 DOI: 10.1111/jors.12524 R E S E A R C H A R T I C L E Public transport, noise complaints, and housing: Evidence from sentiment analysis in Singapore Yi Fan1 | Ho Pin Teo2 | Wayne X. Wan3 1Department of Real Estate, National University of Singapore, Singapore, Singapore 2Department of Building, National University of Singapore, Singapore, Singapore 3Department of Land Economy, The University of Cambridge, Cambridge, UK Correspondence Wayne X. Wan, Department of Land Economy, The University of Cambridge. 19 Silver St, Cambridge CB3 9EP, UK. Email: xw357@cam.ac.uk Funding information National University of Singapore, Grant/Award Number: R‐297‐000‐134‐133 Abstract This paper investigates the effect of a new bus route on noise complaints of residents and the influence of noise on housing price. To overcome the challenge of mapping noise data with subjective emotion, we use a novel data source—text‐based noise complaint records from re- sidents in a town in Singapore—and apply natural language processing tools to conduct sentiment analysis. To address the endogeneity concern regarding the bus route, we use a hypothetical least cost path as an in- strument for the existing bus route. We find that living closer to the bus route for every 100 m increases noise complaints by around 10 percentage points, and the effect is more severe on medium floor levels (5th–8th floors) and near bus stops (within 100 m). We further link noise with housing price and discover a price reduction of 3% with a 1‐scale‐point increase in noise complaints. This implies that bus noise offsets 17.8% of the benefit from convenience, which sheds light on the importance of noise insulation in transit‐ oriented developments. K E Y W O R D S housing, noise, public transport, sentiment analysis This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2021 The Authors. Journal of Regional Science published by Wiley Periodicals LLC. ===== PAGE 12 (score 36, numeric-paren 12, table-words 1, var-words 10) ===== TABLE 1 Summary statistics of noise complaints and housing transactions Total Near = 0 (100–200 m) Near = 1 (within 100 m) Diff ((5)–(8)) N Mean SD N Mean SD N Mean SD t‐test (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) Noise sentiment 593 0.409 0.165 328 0.416 0.170 265 0.399 0.159 0.017 Distance (100 m) 593 1.111 0.493 328 1.483 0.317 265 0.650 0.187 0.833*** LCP (100 m) 593 1.737 1.323 328 2.136 1.349 265 1.243 1.108 0.893*** ECP (100 m) 593 1.068 0.794 328 1.516 0.649 265 0.514 0.578 1.001*** Launch (after = 1) 593 0.575 0.495 328 0.512 0.501 265 0.653 0.477 −0.141*** Near (within 100 m = 1) 593 0.447 0.498 RC center (with = 1) 593 0.069 0.254 328 0.0671 0.251 265 0.072 0.258 −0.005 Building age 593 29.022 2.267 328 28.902 2.584 265 29.170 1.794 −0.267 Floor level 593 6.408 3.960 328 6.479 3.976 265 6.321 3.946 0.158 Morphology 593 2.926 0.293 328 2.878 0.371 265 2.985 0.122 −0.107*** Gender (Male = 1) 527 0.467 0.499 300 0.503 0.501 227 0.419 0.494 0.085* To train station (100 m) 593 2.125 1.155 328 2.435 1.224 265 1.741 0.933 0.693*** To LRT line (100 m) 593 1.531 1.154 328 1.884 1.155 265 1.093 0.994 0.790*** To bus stop (100 m) 593 1.202 0.501 328 1.335 0.548 265 1.038 0.377 0.233*** To expressway (100 m) 593 4.281 2.030 328 4.553 2.357 265 3.945 1.468 0.608*** To major road (100 m) 593 1.217 0.816 328 1.359 0.758 265 1.041 0.851 0.318*** To shopping center (100 m) 593 5.302 2.863 328 5.181 3,154 265 5.452 2.467 −0.271 Price (thousand SGD) 1450 375.207 73.564 1003 364.924 69.114 447 398.282 77.968 −33.359*** (Continues) FAN ET AL. | 581 ===== PAGE 13 (score 6, numeric-paren 1, table-words 0, var-words 4) ===== Total Near = 0 (100–200 m) Near = 1 (within 100 m) Diff ((5)–(8)) N Mean SD N Mean SD N Mean SD t‐test (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) Floor 1450 6.710 3.630 1003 6.671 3.588 447 6.799 3.724 −0.128 Area (m2) 1450 103.595 20.399 1003 99.984 19.56 447 111.696 19.928 −11.712*** Note: Morphology equals to 1 if the block follows the new generation building layout, 2 if it follows the point block layout, or 3 if it follows the slab block layout. Abbreviations: ECP, Euclidean cost path; LCP, least cost path; LRT, light rail train. *p < 0.1. **p < 0.05. ***p < 0.01. 582 | FAN ET AL. ===== PAGE 14 (score 77, numeric-paren 56, table-words 2, var-words 8) ===== TABLE 2 First‐stage IV estimation results of the effects of bus route on noise complaints at individual level (1) (2) (3) (4) Launch × Near Launch × Near Launch × Distance Launch × Distance Launch × ECP −0.3653*** −0.3306*** 0.4184*** 0.4025*** (0.0546) (0.0615) (0.0520) (0.0602) ECP 0.0190 0.0367 −0.0070 −0.0491 (0.0419) (0.0451) (0.0364) (0.0395) Launch × LCP −0.0787** 0.0491 (0.0360) (0.0352) LCP −0.0790 0.1558** (0.0651) (0.0644) Launch 0.7781*** 0.8410*** 0.8278*** 0.7932*** (0.2049) (0.2067) (0.2051) (0.2057) Building age −0.0040 −0.0023 −0.0117 −0.0158 (0.0119) (0.0119) (0.0104) (0.0102) Floor 0.0007 −0.0000 0.0029 0.0033 (0.0123) (0.0126) (0.0102) (0.0105) Floor squared 0.0005 0.0005 −0.0008 −0.0008 (0.0007) (0.0007) (0.0006) (0.0006) Point block 0.0401 0.0605 0.3776** 0.3339** (0.1951) (0.1908) (0.1789) (0.1692) Slab block 0.0943 0.1315 0.1492 0.0789 (0.1448) (0.1457) (0.1397) (0.1330) Male −0.0402 −0.0405 0.0156 0.0149 (0.0299) (0.0286) (0.0239) (0.0228) RC center −0.0094 −0.0105 −0.0135 −0.0083 (0.0796) (0.0803) (0.0684) (0.0692) Block and time fixed effect Y Y Y Y First‐stage F‐Stats 22.69 26.81 32.67 38.07 J‐Statistics (p value) 0.2787 0.2235 Observations 527 527 527 527 Note: Columns (1) and (2) report results for the binary closeness indicator. Columns (3) and (4) report results for the continuous distance variable. Columns (1) and (3) use the ECP, the Euclidean straight lines connecting bus stops, as the instrument. Columns (2) and (4) use both ECP and LCP, the least travel time path, as the instrument. Unreported control variables include distance to train stations, LRT viaduct line, bus stops, expressways, major roads, and shopping centers. Standard errors are clustered by building blocks. Robust standard errors in parentheses. Abbreviations: ECP, Euclidean cost path; LCP, least cost path. *p < 0.1. **p < 0.05. ***p < 0.01. FAN ET AL. | 583 ===== PAGE 15 (score 109, numeric-paren 82, table-words 3, var-words 9) ===== TABLE 3 OLS and second‐stage IV estimation results of the effects of bus route on noise complaints at individual level Noise sentiment (1) (2) (3) (4) (5) (6) OLS ECP IV Both IVs OLS ECP IV Both IVs Launch × Near 0.0496 0.1090** 0.1118** (0.0324) (0.0459) (0.0437) Near −0.0136 −0.0105 −0.0300 (0.0303) (0.0529) (0.0476) Launch × Distance −0.0405 −0.0953** −0.0965** (0.0338) (0.0430) (0.0422) Distance 0.0074 0.0125 0.0301 (0.0328) (0.0462) (0.0423) Launch −0.1123 −0.1330 −0.1365 −0.0400 0.0319 0.0333 (0.1217) (0.1069) (0.1054) (0.1167) (0.1140) (0.1114) Building age −0.0016 −0.0011 −0.0015 −0.0019 −0.0024 −0.0022 (0.0048) (0.0044) (0.0044) (0.0048) (0.0044) (0.0043) Floor −0.0130* −0.0126** −0.0128** −0.0128* −0.0122* −0.0125** (0.0070) (0.0063) (0.0063) (0.0071) (0.0063) (0.0063) Floor squared 0.0008* 0.0007* 0.0007* 0.0008* 0.0007* 0.0007* (0.0004) (0.0004) (0.0004) (0.0004) (0.0004) (0.0004) Point block −0.0487 −0.0764 −0.0593 −0.0423 −0.0457 −0.0415 (0.0811) (0.0786) (0.0786) (0.0792) (0.0739) (0.0728) Slab block −0.0429 −0.0675 −0.0505 −0.0409 −0.0484 −0.0393 (0.0543) (0.0549) (0.0554) (0.0508) (0.0475) (0.0480) Male 0.0181 0.0195 0.0186 0.0171 0.0166 0.0156 (0.0201) (0.0188) (0.0186) (0.0199) (0.0187) (0.0186) RC center 0.0484* 0.0448* 0.0501** 0.0453* 0.0420* 0.0463* (0.0269) (0.0251) (0.0251) (0.0260) (0.0236) (0.0239) Block and time fixed effect Y Y Y Y Y Y Observations 527 527 527 527 527 527 R2 0.214 0.203 0.207 0.213 0.206 0.208 Note: Columns (1)–(3) report results for the binary closeness indicator and Columns (4)–(6) report results for the continuous distance variable. Columns (1) and (4) are OLS estimation results. Columns (2) and (5) use the ECP, the Euclidean straight lines connecting bus stops, as the instrument. Columns (3) and (6) use both ECP and LCP, the least travel time path, as the instrument. Unreported control variables include distance to train stations, LRT viaduct line, bus stops, expressways, major roads, and shopping centers. Standard errors are clustered by building blocks. Robust standard errors in parentheses. *p < 0.1. **p < 0.05. ***p < 0.01. 584 | FAN ET AL. ===== PAGE 16 (score 14, numeric-paren 0, table-words 3, var-words 8) ===== instrument(s), respectively. First‐stage results reveal that both ECP and the combination of ECP and LCP are strongly and statistically significantly correlated with the actual bus service route, controlling for the physical features, gender of the complainants, and the fixed effect from time and building. The F‐statistics in all specifications are around 20–30, miti- gating concerns about weak instruments. For estimations with more instrumental variables than endogenous variables (Columns (2) and (4)), the J‐statistics for over‐identification test are 0.2787 and 0.2235, respectively. Table 3 presents OLS and second‐stage IV estimation results. Column (1) presents OLS estimates from Equation (1), while Columns (2) and (3) display IV estimates using ECP and the combination of ECP and LCP, respectively. Columns (4)–(6) show corresponding estimates from Equation (2). The OLS estimate is positive, though with no statistical significance, in Column (1), and it is likely contaminated by unobserved factors. For example, residents who are less sensitive to noise will choose to live in units closer to roads and will also make less noise complaints. Therefore, the OLS estimate of the noise effect will be downward biased in magnitude. Using ECP as an instrument, being close to the bus service route (within 100 m) results in a higher negative sentiment score of 0.109 (Column (2)) and 0.112 (Column (3)) using both ECP and LCP as IVs. Both of the two IV estimates are statistically significant at the 5% level. Since the sentiment score is normalized to the range of 0 to 1, this indicates that intensification of public transport services worsens the noise sentiment in surrounding public housing by approximately 11 percentage points. The continuous distance effect is estimated to be −0.095 (Column (5)) using ECP as the IV, or −0.097 (Column (6)) using the combined IVs. Both estimates are statistically significant at the 5% level. Consistent with previous findings using a binary indicator of closeness, the distance estimates reveal that by living closer to road traffic by 100 m, the negative noise sentiment will increase by around 10 percentage points on average. One assumption in the interpretations above is that the intensification of the bus service is the only source of changing noise levels along the bus route. A possible concern about the validity of this assumption is that with the newly opened bus route, increased bus traffic will change the traffic patterns of other vehicles on the route. For instance, commuters using private vehicles instead of public buses may choose other routes to avoid congestion. However, under this scenario, the traffic volume from other vehicles is expected to decrease after the treatment, and the measured increase in noise sentiment in buildings near the bus route will be smaller than the real increase due to the new bus. In other words, the real impact of closeness to the new bus service on noise sentiment is likely larger than our estimates. 6.2 | Robustness checks We first examine the robustness of our baseline results by setting different cut‐off distances for the treatment and control groups in the DID estimations. Since the maximum distance to the bus route for buildings in our sample is 198.5 m, we set the cut‐off distance to be 100 m in the baseline estimation to balance sample size in each group. This 100 m boundary for road traffic noise insulation is also supported by the acoustics literature (Avsar & Gonullu, 2005; Martin & Hothersall, 2002). As robustness checks, we follow the same empirical strategy as Equation (1) but change the cut‐off distances to 110 or 90 m. The corresponding estimation results are reported in Appendix Table C1. The estimates are very close to those in our baseline results, for both the magnitude and statistical significance. Another possible concern about the baseline estimation result is that an individual's sentiment about a new noise incident is dependent on previous exposure to noise. If the surrounding environment has been noisy for years, residents may not notice additional noise incidents, while residents living in quiet housing units may be less tolerant of a sudden increase in the noise level. To alleviate this concern, the average sentiment score of noise complaints made in the same building with a 1‐year lag is included as an additional control. Results are reported in Appendix Table C2. The estimates remain robust in magnitude and level of significance. In addition, the occurrence time of noise incidents may impact the noise sentiment, because residents may be disrupted more easily at night. Therefore, we use the report time of the noise complaints as a proxy for the occurrence FAN ET AL. | 585 ===== PAGE 19 (score 43, numeric-paren 16, table-words 6, var-words 11) ===== estimations, using ECP as IV. Results are presented in Panel B of Table 4. Columns (1) and (2) show estimates using the dummy variable measuring closeness, while Columns (3) and (4) present estimates using distance variations. The effects at buildings within 100 m of a bus stop show larger magnitude (0.511 for the binary closeness variable and −0.288 for the continuous distance variable), with statistical significance at the 1% level. This indicates that the noise effect from bus service is more severe around bus drop‐off points. A possible explanation is the influx of visitors around bus stops. Also, it is possible that buses generate more noise when they stop at or leave from the TABLE 4 Heterogeneous effects of bus route on noise complaints Panel A: Noise sentiment across floor levels (1) (2) (3) (4) (5) (6) 1–4 Storey 5–8 Storey Above 8 Storey 1–4 Storey 5–8 Storey Above 8 Storey Launch × Near 0.0738 0.2141*** −0.0290 (0.0674) (0.0799) (0.0802) Launch × Distance −0.0552 −0.2428*** 0.0282 (0.0527) (0.0820) (0.0608) Block and time fixed effect Y Y Y Y Y Y First‐stage F‐stats 14.83 18.11 7.85 32.74 20.66 11.65 Observations 221 144 162 221 144 162 R2 0.477 0.605 0.544 0.479 0.598 0.564 Panel B: Noise sentiment with different distance to bus stops (1) (2) (3) (4) Within 100 m Out of 100 m Within 100 m Out of 100 m Launch × Near 0.5114*** 0.1315* (0.1924) (0.0739) Launch × Distance −0.2875*** −0.1330** (0.0853) (0.0607) Block and time fixed effect Y Y Y Y First‐stage F‐stats 17.24 21.35 38.59 26.27 Observations 179 348 179 348 R2 0.447 0.274 0.590 0.314 Note: Columns (1)–(3) of Panel A report results for the binary closeness indicator. Columns (4)–(6) of Panel A report results for the continuous distance variable. Columns (1) and (2) of Panel B report results for the binary closeness indicator. Columns (3) and (4) of Panel B report results for the continuous distance variable. All estimations use ECP, the Euclidean straight lines connecting bus stops, as the instrument. Unreported control variables include building age, floor and floor squared, gender, morphology, RC center, and distance to train stations, LRT viaduct line, bus stops, expressways, major roads, and shopping centers. Standard errors are clustered by building blocks. Robust standard errors in parentheses. *p < 0.1. **p < 0.05. ***p < 0.01. 588 | FAN ET AL. ===== PAGE 20 (score 61, numeric-paren 42, table-words 3, var-words 8) ===== TABLE 5 Net effects of the new bus service on housing price (1) (2) log (price) log (price) Launch × Near 0.0129** (0.0054) Near −0.0097** (0.0038) Launch × Distance −0.0134*** (0.0050) Distance 0.0104*** (0.0037) Launch 0.0101 0.0299*** (0.0077) (0.0094) Prime lending rate −2.8766*** −2.8815*** (0.3558) (0.3563) Floor 0.0070*** 0.0070*** (0.0003) (0.0003) Area 0.0030*** 0.0030*** (0.0008) (0.0008) Building age −0.0009 −0.0009 (0.0006) (0.0006) Distance to train station −0.0035** −0.0036** (0.0015) (0.0015) Distance to bus stop −0.0042 −0.0046 (0.0031) (0.0032) Distance to expressway 0.0025*** 0.0024*** (0.0008) (0.0008) Distance to major road −0.0014 −0.0010 (0.0016) (0.0017) Distance to shopping center 0.0037*** 0.0037*** (0.0009) (0.0009) Block and time fixed effect Y Y Observations 1450 1450 R2 0.941 0.941 Note: Column (1) reports results for the binary closeness indicator and column (2) reports results for the continuous distance variable. Unreported control variables include building morphology and RC center. Standard errors clustered by building blocks. Robust standard errors in parentheses. *p < 0.1. **p < 0.05 ***p < 0.01. FAN ET AL. | 589 ===== PAGE 21 (score 49, numeric-paren 25, table-words 4, var-words 13) ===== bus stops. In addition, with frequent visual exposure to noise sources at bus stops, subjective feelings of annoyance by surrounding residents may be intensified. 7 | COST‐BENEFIT ANALYSIS: PUBLIC TRANSPORT AND HOUSING PRICE Public transport offers convenience to surrounding residents, and thus raises housing price in the neighborhood (Chalak et al., 2016; Cohen & Paul, 2007; Holmgren, 2014; Monchambert & De Palma, 2014). Nonetheless, it also generates noise pollution, which exerts a negative impact on the housing price (Diao et al., 2016). To implement a cost‐benefit analysis, we start with an estimation on the overall impact of the new bus route on housing price. Specifically, we follow the same specification in Equations (1) and (2), but replace the dependent variable of noise sentiment with housing price (Diao et al., 2017): β β β θ μ φ ω ε = + + ∗ + + + + + ′ ′ Price Near Launch Launch Near X U log ( ) , ijt i t t i i j t i ijt 1 2 3 (6) β β β θ μ φ ω ε = + + ∗ + + + + + ′ ′ Price Distance Launch Launch Distance X U log ( ) . ijt i t t i i j t i ijt 1 2 3 (7) TABLE 6 Effects of noise complaints on housing price (1) (2) log (price) log (price) Noise sentiment in previous 12 months −0.0300** −0.0262** (0.0149) (0.0132) Noise sentiment in previous 12 months × Low/high floors −0.0053 (0.0084) Distance to nearest bus stop connecting CBD −0.0027* −0.0027* (0.0016) (0.0016) Prime lending rate −3.5344*** −3.5089*** (0.4423) (0.4638) Floor 0.0064*** 0.0065*** (0.0005) (0.0006) Area 0.0075*** 0.0075*** (0.0002) (0.0002) Building age −0.0035*** −0.0035*** (0.0009) (0.0009) Block and time fixed effect Y Y Observations 893 893 R2 0.919 0.919 Note: Unreported control variables include unit layout, building morphology, RC center, and distance to train stations, LRT viaduct line, bus stops, expressways, major roads, and shopping centers. Standard errors are clustered by building blocks. Robust standard errors in parentheses. *p < 0.1. **p < 0.05. ***p < 0.01. 590 | FAN ET AL. ===== PAGE 22 (score 29, numeric-paren 0, table-words 9, var-words 11) ===== The definitions for the other variables are the same as in Equations (1) and (2). Table 5 displays the corresponding results using all of the resale transaction data in our study area from 2010 to 2018. Column (1) reveals that before the bus starts operation, the housing prices within 100 m of the route are 0.97% lower than those farther away (100–200 m). This is probably because the route is designed along the community road, generating traffic noise but offering limited convenience before the new bus service begins. After the introduction of bus service, the housing price within 100 m of the bus route increases by 1.3% compared to units within 100–200 m of the bus route. A similar conclusion can be drawn if we use a continuous variable of distance to estimate the benefit from the convenience of public transport (Column (2)). The prices for units closer to the new bus route by 100 m increase by 1.34%. The estimate is statistically significant at the 1% level. Nevertheless, this explicit benefit is likely to be offset by an implicit decrease in housing price due to the noise generated by the new bus route. We thus examine the negative effect of noise sentiment on housing price using the same set of resale transaction records. Column (1) in Table 6 presents the corresponding OLS regression results of Equation (3). We include all the transaction records in our study area which can be matched with the lagged noise sentiment. To estimate the exact economic costs of noise pollution on housing price, we also control for the distance to the nearest bus stop connecting the CBD before and after the launch of bus no. 972. It reveals that a 1‐scale‐point increase in noise sentiment over the past 12 months is correlated with a 3% decrease in housing price.9 This estimate is statistically significant at the 5% level. Finally, we analyze the cost and benefit for intensifying public transport on housing price. Since living closer to the new bus service route by 100 m has caused the noise sentiment score to increase by around 9.53% (Column (5) in Table 3), the negative effect of its noise on housing price can be interpolated as approximately 0.29% per 100‐m distance to the bus route. Taking the explicit 1.34% increase in housing price per 100 m closer to the new bus route, we estimate that the implicit effect of traffic noise on housing value has offset around 17.79% of the economic benefit brought by the improvement of public transport. We also investigate the heterogeneous impact of noise from the new bus route on housing price across floor levels in two steps. First, we examine the heterogeneous impact of the new bus service on noise sentiment on low, medium, and high floors. We find that the noise nuisance from the new bus service is positive and statis- tically significant on medium floors only, as reported in Table 4. Second, we estimate the impact of sentiment from general noise on housing price across floor levels. Specifically, we modify Equation (3) by interacting − SIi t, 1 with a dummy variable denoting the units on the low and high floors. The estimation results are reported in Column (2), Table 6. We find that if the 1‐year lagged noise sentiment increases by 1 scale point, the housing price on medium floors decreases by 2.62%. This estimate is statistically significant at the 5% level. In addition, the overall impact of a 1‐scale‐point increase in sentiment from general noise on housing price is similar across housing units on low/high floors and on medium floors, which is reflected by the statistically insignificant coefficient for the interaction term between the lagged noise sentiment and the dummy variable for units on low/high floors. Combining the results from these two steps, we conclude that for units on medium floors, a decrease of distance to the bus route by 100 meters increases the noise sentiment by 24.3 percentage points (Column (5) in Panel A, Table 4), which translates to a 0.64% drop in housing price, or equivalently, a loss of around 2401 SGD (1766 USD) per housing unit. In comparison, for units on high/low floors, as the impact of the new bus service on noise sentiment is statistically insignificant (Columns (4) and (6) in Panel A, Table 4), the direct impact of noise from the new bus on housing price is likely small. 9The results remain robust if we use the noise sentiment over the past 6 months instead. The estimation results are reported in Appendix Table C8. FAN ET AL. | 591