What are the consequences of including a “don’t know” (DK) response option to attitudinal survey questions? Existing research, based on traditional survey modes, argues that it reduces the effective sample size without improving the quality of responses. We contend that it can have important effects not only on estimates of aggregate public opinion, but also on estimates of opinion differences between subgroups of the population who have different levels of political information. Through a pre-registered online survey experiment conducted in the United States, we find that the DK response option has consequences for opinion estimates in the present day, where most organizations rely on online panels, but mainly for respondents with low levels of political information and on low salience issues. These findings imply that the exclusion of a DK option can matter, with implications for assessments of preference differences and our understanding of their impacts on politics and policy.

Get natural gas historical data, energy prices historical data, and more. ICE Endex iMpact is the primary data feed for ICE Endex, the leading energy exchange in continental Europe. It covers a diverse range of energy products, including European gas, emissions, and power markets, providing valuable data for energy firms, EU ETS compliance entities, and financial participants to effectively manage price risk. This dataset includes all listed spot contracts, outrights, spreads, options, and options combinations on ICE Endex.

Asset class: Futures, Options

Origin: Captured at Aurora DC3 with an FPGA-based network card and hardware timestamping. Synchronized to UTC with PTP

Supported data encodings: DBN, CSV, JSON (Learn more)

Supported market data schemas: MBO, MBP-1, MBP-10, TBBO, Trades, OHLCV-1s, OHLCV-1m, OHLCV-1h, OHLCV-1d, Definition, Statistics (Learn more)

Resolution: Immediate publication, nanosecond-resolution timestamps

This study examines the impact of option listing on the volatility of underlying commodity futures markets in China. We construct the counterfactual volatility for these optioned commodity futures and estimate the average treatment effect of option listing. Using a panel data approach based on Hsiao et al. (2012), referred to as HCW, we incorporate conventional information criteria (including AIC, AICC and BIC) as well as the LASSO (Least Absolute Shrinkage and Selection Operator) method to select optimal control units from a large set of alternatives for the treatment units.

This paper estimates both option values and spillover damages associated with parcel-level coastal armoring in Oregon. This repository provides a Stata .do file for replication of main results of the paper. Proprietary housing data from CoreLogic was used in our analysis so we are unable to share our full data set. Data files are included with proprietary data deleted with a text string as placeholders.

Note. Each problem required participants to choose between a risky option (X with probability pnon-zero or $0 with probability 1 − pnon-zero) and a certain option (Y with probability 1.0). The value of Y was either slightly above or below the expected value of the risky option.Choice problems.

Browse EUA Futures Options (Futures Style Margin) (EFO) market data. Get instant pricing estimates and make batch downloads of binary, CSV, and JSON flat files.

ICE Endex iMpact is the primary data feed for ICE Endex, the leading energy exchange in continental Europe. It covers a diverse range of energy products, including European gas, emissions, and power markets, providing valuable data for energy firms, EU ETS compliance entities, and financial participants to effectively manage price risk. This dataset includes all listed spot contracts, outrights, spreads, options, and options combinations on ICE Endex.

Asset class: Futures, Options

Origin: Captured at Aurora DC3 with an FPGA-based network card and hardware timestamping. Synchronized to UTC with PTP

Supported data encodings: DBN, CSV, JSON (Learn more)

Supported market data schemas: MBO, MBP-1, MBP-10, TBBO, Trades, OHLCV-1s, OHLCV-1m, OHLCV-1h, OHLCV-1d, Definition, Statistics (Learn more)

Resolution: Immediate publication, nanosecond-resolution timestamps

An important feature of postsecondary schooling is the experimentation that accompanies sequential decision making. Specifically, by entering college, a student gains the option to decide at a future time whether it is optimal to remain in college or to drop out, after resolving uncertainty that existed at entrance about factors that affect the return to college. This paper uses data from the Berea Panel Study to quantify the value of this option. The unique nature of the data allows us to make a distinction between actual option values and perceived option values and to examine the accuracy of students' perceptions.

Browse Robusta Coffee Options (RC) market data. Get instant pricing estimates and make batch downloads of binary, CSV, and JSON flat files.

ICE Futures Europe iMpact is the primary data feed for ICE Futures Europe and covers 50% of worldwide crude and refined oil futures trading, as well as other options and futures contracts like natural gas, power, coal, emissions, and soft commodities. This dataset includes all commodities on ICE Futures Europe—all listed outrights, spreads, options, and options combinations across every expiration month. Interest rates and financial products are not included at this time and will be part of a separate dataset.

Asset class: Futures, Options

Origin: Captured at Aurora DC3 with an FPGA-based network card and hardware timestamping. Synchronized to UTC with PTP

Supported data encodings: DBN, CSV, JSON (Learn more)

Supported market data schemas: MBO, MBP-1, MBP-10, TBBO, Trades, OHLCV-1s, OHLCV-1m, OHLCV-1h, OHLCV-1d, Definition, Statistics (Learn more)

Resolution: Immediate publication, nanosecond-resolution timestamps

According to a 2023 survey, around 42 percent of consumers in the United Kingdom (UK) stated that a lack of their preferred delivery option stopped them from making a purchase with a retailer. However, a similar share reported that the non-availability of their favored delivery option did not deter them from online shopping.

PERFORMANCE STANDARDS OPTION (PSO) OVERLAY: The purpose of this chapter is to allow an option for more flexible design than is permissible under the conventional zoning codes. The design should stress energy efficiency, architectural creativity, and innovation; use the natural features of the landscape to their greatest advantage; provide a quality of life equal to or greater than that provided in developments built under the standard zoning codes; be aesthetically pleasing; provide for more efficient land use; and reduce the impact of development on the natural environment and neighborhood. See AMC 18.3.9 et. seq.

The options trading platform market is experiencing robust growth, driven by increasing retail investor participation, the rise of mobile trading, and the growing popularity of options strategies for income generation and risk management. The market, estimated at $15 billion in 2025, is projected to achieve a compound annual growth rate (CAGR) of 12% from 2025 to 2033. This expansion is fueled by several key factors. Firstly, the democratization of finance, with user-friendly platforms lowering the barrier to entry for individual investors, has significantly broadened the market's addressable audience. Secondly, the increasing availability of educational resources and online communities dedicated to options trading is empowering newcomers to confidently engage with this sophisticated asset class. Technological advancements, specifically the development of sophisticated yet intuitive mobile trading apps, have further contributed to market growth by providing convenient and accessible options trading capabilities anytime, anywhere. However, market growth is not without its challenges. Regulatory scrutiny of options trading platforms, aimed at protecting investors from excessive risk-taking, could act as a restraint. Furthermore, market volatility and potential economic downturns can impact investor sentiment and trading activity, thereby affecting overall market growth. The segmentation of the market reveals a dynamic landscape. Cloud-based platforms are gaining significant traction due to their scalability and accessibility, while the enterprise segment continues to dominate in terms of revenue generation due to higher trading volumes. Key players in the market, including established brokerages like Interactive Brokers, Charles Schwab, and Fidelity, alongside innovative fintech companies such as Robinhood and tastyworks, are constantly vying for market share through technological innovation, enhanced user experience, and competitive pricing strategies. The regional distribution of the market reveals a strong concentration in North America, followed by Europe and Asia Pacific, with growth opportunities anticipated in emerging markets as financial literacy improves.

?, insufficient evidence to warrant definitive decision; +, available evidence suggests this is a beneficial option, compared to the other expansion options; −, available evidence suggests this is an unfavourable option, compared to the other expansion options; •, available evidence supports neither that this is a beneficial option nor that it is an unfavourable option.

According to a recent survey conducted among online shoppers in the United Kingdom (UK), coronavirus-specific options was the least important factor for the customers both in lockdown and post-lockdown conditions. Over the four-month period, the easing of COVID-19 measures has decreased the importance of this criteria as its share among the respondents changed from 75 percent in May to 63 percent in August 2020.

This survey experiments analyses the effects of different ballot question structures on voting behaviour. Two types of questions are posed on the topic of reducing the maximum speed limit: one with ordinal alternatives (various speed limits) and one with categorical alternatives (alternative scenarios for applying speed limits). Respondents are questioned on these alternatives using two question structures: a single multi-option question and multiple binary questions. The experimental data can be used to analyse to which extent the question type, ballot question structure and order in which alternatives are offered affect voting behaviour.

Browse Brent Crude American-style Options (BRN) market data. Get instant pricing estimates and make batch downloads of binary, CSV, and JSON flat files.

ICE Futures Europe iMpact is the primary data feed for ICE Futures Europe and covers 50% of worldwide crude and refined oil futures trading, as well as other options and futures contracts like natural gas, power, coal, emissions, and soft commodities. This dataset includes all commodities on ICE Futures Europe—all listed outrights, spreads, options, and options combinations across every expiration month. Interest rates and financial products are not included at this time and will be part of a separate dataset.

Asset class: Futures, Options

Origin: Captured at Aurora DC3 with an FPGA-based network card and hardware timestamping. Synchronized to UTC with PTP

Supported data encodings: DBN, CSV, JSON (Learn more)

Supported market data schemas: MBO, MBP-1, MBP-10, TBBO, Trades, OHLCV-1s, OHLCV-1m, OHLCV-1h, OHLCV-1d, Definition, Statistics (Learn more)

Resolution: Immediate publication, nanosecond-resolution timestamps

Evaluating the impacts of limiting free choice in management option selection by Entry Level Stewardship (ELS) applicants

In 2022, more than half of Polish respondents stated that they would not take a job with a company that does not comply with the baseline ESG requirements.

The dataset contains estimates of how different scenarios of agricultural subsidy reform could affect agricultural production, food consumption, environmental impacts, diet-related health impacts, and economic impacts.

The results have been published as: Springmann, M, Freund, F. Options for reforming agricultural subsidies from health, climate, and economic perspectives. Nature Communications (accepted 30 November 2021)

During decision−making, animals consider not only the current but also the past quality of options. For example, when humans evaluate performance (e.g. sales) of employees, they do not only consider the average performance but also the trend of performance　ascending performance is often viewed as more favorable than descending performance. In our study, we test if non-human animals have a similar bias when they are evaluating options using house-hunting by the acorn ant, Temnothorax curvispinosus, as our model system. Our data show that when nest-site quality is static over time, ant colonies tend to prefer the nest site which was better (i.e. darker) between two nest options. However, when the nest quality changes—one improves and the other worsens—over time, more colonies choose the low-quality, but improving, nest than the high-quality, but worsening, nest. These results suggest that a continuous change of option quality may influence evaluation. We discuss alternative explanations for our results, possible mechanisms and potential ecological benefits for keeping track of the nest-site quality. Methods Experimental procedure Prior to the experiment, we induced a colony emigration to an empty home nest placed in the middle of the experimental arena (19 x 27 cm) (see Sasaki and Pratt 2018 for the detail of the emigration procedure). After 24 hours, we introduced two kinds of potential target nests, namely an “improving” nest and a “worsening” nest, one on each side (Figure 1a). These target nests were identical to the home nest except the interior light level, which was controlled by putting light filters on the roof (see Supplementary Information for the detail of the nest design; Figure S1). The home nest was always darker than target nests to prevent early migration. The improving nest initially had a very bright interior light level (approx. 1600 lux) but became darker, and more preferable (Franks et al. 2003; Sasaki et al. 2019), over time (Figure 1b). The interior light level of the worsening nest, on the other hand, was initially very dark (approx. 3 lux) but became brighter, and less preferable, over time (Figure 1b). Note that the interior light level of the worsening nest was always darker, thus more preferable, than that of the improving nest until day 4. Temnothorax ants have low sensitivity to light within a bright range, and thus light levels were chosen based on the previous finding (Sasaki et al. 2013). Every morning until day 5, we adjusted the interior light level by replacing the light filters of the secondary roof. To minimize changing the environmental cues, we used the same glass slides for the secondary roof throughout the experiment. To test whether decisions were influenced by the trend in quality, both potential nests had the same interior light level (approx. 400 lux) on day 5, and, on the following day (day 6), the roof of the home nest was removed to induce an emigration. We chose five days as the duration of the experiment based on the previous studies, which showed that Temnothorax ants retain nest information for at least six days (Langridge et al. 2004; Santos et al. 2022). We assayed nest-site preference by recording the site occupied by the colony 12 hours later. If one site contained more than 90% of colony members including all queens and brood items, we designated that as the choice. If no site achieved this criterion, we did not record a preference. This occurred only once out of a total of 30 tests. Until the roof of the home nest was removed on day 5, the interior light level of the home nest (approx. 1 lux) was always darker than those of the target nests, so the colony stayed at the home nest although some scouts might visit and assess these potential nests throughout the experiment. To confirm these visits and measure the number of scouts, we recorded the number of ants in the target nests at around 9 am each day until the secondary roof was replaced for each of the 10 colonies. The food (the agar-based diet (Bhatkar and Whitcomb 1970) and spam meat) and water tube were placed next to the home nest (Figure 1a) throughout the experiment. The arenas had three photography LED lights above them and received 1540-1690 lux light intensity. Note that the interior light levels reported above are estimations based on the light transmittance (i.e. f-stop) of the light filters. In addition to the “trend” condition described above, we also conducted two additional conditions as control conditions. In both the control conditions, the procedure was identical to the one used for the trend condition except that the interior light levels of the target nests were constant over time until day 4. In the “average” control condition and the “last-point” control condition, the interior light levels of the target nests were the average of the light levels for each nest type (1024 lux for the improving nest and 88 lux for the worsening nest) and the last level for each nest type (565 lux for the improving nest and 200 lux for the worsening nest), respectively (Figure 1c). On day 5, the light level for the target nests became identical (400 lux), and the roof of the home nest was removed to induce emigration. Out of the 30 tests conducted for each of the two control conditions, six tests in the average condition and two tests in the last-point condition did not achieve the consensus criterion. We used 30 colonies (see Supplementary Material for the detail of the subjects), all of which were tested for each condition, and the order of the conditions was randomized for each colony. The interval between the tests was at least two weeks. Before each test, all glass slides were washed using a commercial dishwasher, and the experimental arena was cleaned with ethanol. Cardboard plates were made fresh for each test and never reused. Colonies in the trend condition chose the improving nest over the worsening nest more frequently than the ones in the average condition did, suggesting that the nest-quality change influenced the nest preference (i.e. the nest with improving quality became more preferable than the one with worsening quality). However, because there was not a significant preference for the poor nest site in the trend condition (see Results for details), one possible alternative hypothesis was that the nest-quality change impaired the ability to assess nest quality (Burns et al. 2016), leading to no nest-site preference. To test this hypothesis, we collected additional 29 colonies (see Supplementary Material for the detail of the subjects) and ran another experiment similar to the trend condition. In this “follow-up trend” condition, we also changed the qualities of two nests—one improved and the other worsened over time—but, unlike the trend condition, the quality of the improving nest was better than that of the worsening nest in later days (days 3 and 4; Figure 1d). Note that the means of these over-time qualities were the same (approx. 700 lux). All colonies were tested only once, and four colonies did not achieve the consensus criterion. In the follow-up trend condition, we did not record the number of ants in the target nests each day as we did for the trend and control conditions.
Analysis Preferences in the binary choice were assayed with a χ2 goodness of fit test. The effect of the nest-quality change was tested with a χ2 test of independence. We have removed the choices that did not achieve the criterion for consensus. We ran a generalized linear mixed-effects model (GLMER) and tested colony size (the numbers of workers and brood) and order of the test as fixed effects and colony ID as a random effect . The statistical software R (v. 4.1.2) was used for all analyses. The data and code can be accessed online (Tyler et al. 2023).