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You are an expert at identifying data availability statements in scientific text. A data availability statement describes where research data can be found or how it can be accessed.<|eot_id|><|start_header_id|>user<|end_header_id|>

Determine if the following text contains a data availability statement. Answer with 'yes' or 'no'.

Text: The instrumental variables strategy isolates changes in visitation from within - park variation in ozone that is due to ozone changes in counties that are upwind of every park . The maintained identification assumption is that changes in upwind ozone concentrations are both correlated with in - park ozone concentations and uncorrelated with omitted factors that may bias the OLS estimates . The IV estimate ( column 4 ) is larger than the fixed effects model . The estimate suggests that a 1 ppb increase in average maximum ozone concentrations reduces average monthly visitation by approximately 4 % . The larger estimated impact could be due to the instrument correcting for measurement error in park ozone monitor data ( i.e. , classical measurement error ) , additional unobserved confounders not controlled for in the fixed effects specifications , or because parks with strongly correlated upwind ozone are also the parks with the highest ozone levels ( i.e. , a stronger local average treatment effect ) . Kleibergen - Paap F statistics show that the instrument is strong , and the estimates are statistically significant at the 5 % level . Panel A replaces monthly maximum daily 8 - hour ozone readings with the monthly average of the daily average 1 - hour ozone readings . We include both the fixed effects and IV specifications . We find larger and more precisely estimated negative effects in both specifications . A 1 ppb increase in average ozone concentrations is associated with a 1.9 % and 4.9 % decrease in visitation in the fixed effects and instrumental variables specifications , respectively .<|eot_id|><|start_header_id|>assistant<|end_header_id|>

no<|eot_id|>