184 research outputs found
Food Habits & the Utilization of Drift Organisms by Larval Fishes in the Middle Fork of Drake\u27s Creek, Kentucky
Food habits of larvae of the northern hog sucker, common shiner, rosyface shiner, and Micropterus sp. from the Middle Fork of Drake\u27s Creek, Kentucky were identified from 18 March to 12 August 1982. Eighteen taxa of animals were observed in the stream drift and a total of seventeen taxa, including larval fish, were identified in the stomach analysis. Eggs, rotifers, hydracarina, and diptera represented the greatest component of the drift comprising 34%, 32%, 8%, and 6%, respectively. The major organisms observed in the gut analysis included eggs (fish, rotifer, and copepod species), rotifers (Euchlanis sp.), diptera (Chironomidae), annelida (Naididae), copepoda (cyclopoids), and cladocera (Alona, Camptocercus, and unknown spp.). The northern hog sucker had the most diverse diet ingesting 15 different taxa, whereas the rosyface shiner consumed only 8 taxa. Rosyface shiners selected rotifers in their diet during their first four weeks of life and during the last two weeks as larvae (Ivlev\u27s Electivity Index). shiners selected for week while selecting hog suckers selected a greater variety of organisms during their only for dipterans during their last week. for dipterans Common first Northern annelids, dipterans, and copepods throughout their larval period. Micropterus sp. selected rotifers, annelids, cladocerans, and copepods during their first two weeks and annelids, cladocerans, and copepods during their last four weeks as larvae. Piscivory was observed in Micropterus sp. during the third week of life with 12% of the meta-larvae consuming other larvae. With the exception of Micnoptetuz sp., larvae ingested progressively more taxa as they developed from pro - to meta-larvae. The greatest percentage of empty stomachs in all species was observed in the pro-larvae and the fewest in the meta-larvae. Likewise, the rosyface shiner had the greatest percentage of empty stomachs of the four major species studied.
Even as larvae, the four species studied demonstrated resource sharing and positive interrelationships in their food habits
Humans vs. Machines: Comparing Coding of Interviewer Question-Asking Behaviors Using Recurrent Neural Networks to Human Coders
Standardized survey interviewing techniques are intended to reduce interviewers’ effects on survey data. A common method to assess whether or not interviewers read survey questions exactly as worded is behavior coding. However, manually behavior coding an entire survey is expensive and time-consuming. Machine learning techniques such as Recurrent Neural Networks (RNNs) may offer a way to partially automate this process, saving time and money. RNNs learn to categorize sequential data (e.g., conversational speech) based on patterns learned from previously categorized examples. Yet the feasibility of an automated RNN-based behavior coding approach and how accurately this approach codes behaviors compared to human behavior coders are unknown.
In this poster, we compare coding of interviewer question-asking behaviors by human undergraduate coders to the coding of transcripts performed by RNNs. Humans transcribe and manually behavior code each interview in the Work and Leisure Today II telephone survey (AAPOR RR3=7.8%) at the conversational turn level (n=47,900 question-asking turns) to identify when interviewers asked questions (1) exactly as worded, (2) with minor changes (i.e., changes not affecting question meaning), or (3) with major changes (i.e., changes affecting question meaning). With a random subset of interview transcripts as learning examples, we train RNNs to classify interviewer question-asking behaviors into these same categories. A random 10% subsample of transcripts (n=94) were also coded by master coders to evaluate inter-coder reliability. We compare the reliability of coding (versus the master coders) by the human coders with the reliability of the coding (versus the master coders) by the RNNs. Preliminary results indicate that the human coders and the RNNs have equal reliability (p\u3e.05) for questions with a large proportion of major and minor changes. We conclude with implications for behavior coding telephone interview surveys using machine learning in general, and RNNs in particular
Ranking: Perceptions of Tied Ranks and Equal Intervals on a Modified Visual Analog Scale
This study examined a novel paper-based ranking system (called the BINS format) that was designed to address two limitations of traditional ranking formats. This new system allows respondents to: 1) assign ties to ranked alternatives and 2) indicate distance between ranked alternatives. Participants reported high satisfaction with the ability to express ties using the BINS format, and preferred to use a ranking format that allowed for ties over a format that did not. Two versions of the BINS format (a numbered continuum and an unnumbered continuum) were compared to examine participants’ perception of the distance between ranked alternatives. When a numbered continuum was used, participants saw the relationship between ranked alternatives as both multiplicative and divisible; conversely, participants using the unnumbered continuum did not see either relationship. This lends support to the notion that participants perceived the numbered BINS format as having equal psychological intervals
Why Do Cell Phone Interviews Last Longer? A Behavior Coding Perspective
Why do telephone interviews last longer on cell phones than landline phones? Common explanations for this phenomenon include differential selection into subsets of questions, activities outside the question-answer sequence (such as collecting contact information for cell-minute reimbursement), respondent characteristics, behaviors indicating disruption to respondents’ perception and comprehension, and behaviors indicating interviewer reactions to disruption. We find that the time difference persists even when we focus only on the question-answer portion of the interview and only on shared questions (i.e., eliminating the first two explanations above). To learn why the difference persists, we use behavior codes from the U.S./Japan Newspaper Opinion Poll, a dual-frame telephone survey of US adults, to examine indicators of satisficing, line-quality issues, and distraction. Overall, we find that respondents on cell phones are more disrupted, and that the difference in interview duration occurs because cell phone respondents take longer to provide acceptable answers. Interviewers also slow their speed of speech when asking questions. A slower speaking rate from both actors results in a longer and more expensive interview when respondents use cell phones.
Includes Supplementary Data
How Do Interviewers and Respondents Navigate Sexual Identity Questions in a CATI Survey?
Survey-based research has demonstrated that sexual minority individuals experience unique outcomes in areas such as physical and mental health (Boehmer et al. 2007; Hatzenbuehler 2014, 2017), crime (Herek 2009), public education (Kosciw et al. 2015), same-sex romantic relationships and family (Powell and Downey 1997; Umberson et al. 2015), and economics (Black et al. 2007). Having a reliable and valid measure of sexual identity (i.e., the way in which an individual self-describes their sexual orientation) (Gagnon and Simon 1973) is essential for conducting research on sexual minorities. Indeed, many national surveys such as the General Social Survey, the National Health Interview Survey, and the National Survey of Family Growth ask survey respondents about their sexual identity.
The percentage of US adults identifying as a sexual minority has increased from 3.5% (8.3 million) in December 2012 to 4.1% (10.05 million) in December 2016 (Gates 2017). As the prevalence of sexual minorities is still low, inaccurate answers or item nonresponse to sexual identity questions (SIQs) may result in large distortions of estimates of sexual minorities. In a meta-analysis, Ridolfo et al. (2012) demonstrate that item nonresponse rates for SIQs range from 1.6% to 4.3%, with an average of approximately 2%. For context, this places item nonresponse for SIQs higher than education questions (1.1%), but below income questions (11.2%) (Conron et al. 2008). The threat of item nonresponse due to concerns over question sensitivity has led many researchers to advocate against the use of interviewers to administer SIQs (SMART 2009; Ridolfo et al. 2012). Instead, they recommend that survey researchers ask SIQs using only self-administered modes of data collection (i.e., using mail surveys, web surveys, or Computer-Assisted Self-Interview [CASI] devices for face-to-face surveys) (SMART 2009; Ridolfo et al. 2012).
Yet asking SIQs exclusively in a self-administered context may not be a feasible approach. First, self-administered modes are not without drawbacks of their own: mail surveys are time consuming, face-to-face surveys using CASI are time consuming and expensive, and web surveys do not have a sampling frame with adequate coverage of the US population (Dillman et al. 2014). In contrast, researchers using telephone surveys can collect nationally representative data quickly. Second, while SIQs provide important demographic information, they are often not the primary focus of a survey. Many private survey companies (e.g., Pew, Gallup, Abt Associates) and government surveys (e.g., the Behavioral Risk Factor Surveillance System) rely on telephone surveys to achieve a variety of cost, quality, and timeliness objectives; these organizations are not likely to switch modes to improve data quality for a single demographic question like sexual identity. Thus, understanding the implications of administering SIQs in all modes, including telephone, is of continued interest
Food Habits and the Utilization of Drift Organisms by Larval Fishes in the Middle Fork of Drake\u27s Creek, Kentucky
Food habits of larvae of the northern hog sucker, common shiner, rosyface shiner, and Micropterus sp. from the Middle Fork of Drake\u27s Creek, Kentucky were identified from 18 March to 12 August 1982. Eighteen taxa of animals were observed in the stream drift and a total of seventeen taxa, including larval fish, were identified in the stomach analysis. Eggs, rotifers, hydracarina, and diptera represented the greatest component of the drift comprising 34%, 32%, 8%, and 6%, respectively. The major organisms observed in the gut analysis included eggs (fish, rotifer, and copepod species), rotifers (Euchlanis sp.), diptera (Chironomidae), annelida (Naididae), copepoda (cyclopoids), and cladocera (Alona, Camptocerus, and unknown spp.). The northern hog sucker had the most diverse diet ingesting 15 different taxa, whereas the rosyface shiner consumed only 8 taxa. Rosyface shiners selected for rotifers in their diet during their first four weeks of life and dipterans during the last two weeks as larvae (Ivlev\u27s Electivity Index). Common shiners selected for a greater variety of organisms during their first week while selecting only for dipterans during their last week. Northern hog suckers selected annelids, dipterans, and copepods throughout their larval period. Micropterus sp. selected rotifers, annelids, cladocerans, and copepods during their first two weeks and annelids, cladocerans, and copepods during their last four weeks as larvae. Piscivory was observed in Micropterus, sp. during the third week of life with 12% of the meta-larvae consuming other larvae. With the exception of Micropterus sp., larvae ingested progressively more taxa as they developed from proto meta-larvae. The greatest percentage of empty stomachs in all species was observed in the pro-larvae and the fewest in the meta-larvae. Likewise, the rosyface shiner had the greatest percentage of empty stomachs of the four major species studied. Even as larvae, the four species studied demonstrated resource sharing and positive interrelationships in their food habits
Your Best Estimate is Fine. Or is It?
Providing an exact answer to open-ended numeric questions can be a burdensome task for respondents. Researchers often assume that adding an invitation to estimate (e.g., “Your best estimate is fine”) to these questions reduces cognitive burden, and in turn, reduces rates of undesirable response behaviors like item nonresponse, nonsubstantive answers, and answers that must be processed into a final response (e.g., qualified answers like “about 12” and ranges). Yet there is little research investigating this claim. Additionally, explicitly inviting estimation may lead respondents to round their answers, which may affect survey estimates. In this study, we investigate the effect of adding an invitation to estimate to 22 open-ended numeric questions in a mail survey and three questions in a separate telephone survey. Generally, we find that explicitly inviting estimation does not significantly change rates of item nonresponse, rounding, or qualified/range answers in either mode, though it does slightly reduce nonsubstantive answers for mail respondents. In the telephone survey, an invitation to estimate results in fewer conversational turns and shorter response times. Our results indicate that an invitation to estimate may simplify the interaction between interviewers and respondents in telephone surveys, and neither hurts nor helps data quality in mail surveys
“I Don’t Need No White Validation”: On Blackness, Belonging, And Community In The Southeastern United States
This project is an autoethnographic sharing of my embodied experiences as a black person in predominantly white spaces. Specifically, I choose to think through my (and some others whom I love) experiences in punk and DIY (do-it-yourself) spaces; these are spaces that are close to my heart, spaces that have, and can, feel like a home. Sometimes, these DIY spaces can feel like a home in which I am in a plastic hamster ball, meandering around, but feeling separated by some things, and someones, which can result in alienation. This project is concerned with working through this “weirdness” of the body and body-centered knowledges of anti-black violence in examining the contrasts between white experiences of reality and what Christina Sharpe (2016) calls “the wake,” an “afterlife” of slavery. By doing so, I hope to contribute to on-going conversations about knowledge production, black being, and ideas of community in spaces that both racialized and non-racialized (white) bodies occupy, whereanti-racist liberation is valued, but nonetheless subject to the complications and intricacies of racism and the resulting hierarchization of oppression(s)
Temporal Use Patterns of Wintering Starlings at a Southeastern Livestock Farm: Implications for Damage Control
The farm use patterns of individually marked and transmitter-equipped starlings at a livestock farm in south-central Kentucky were studied each month during the principal damage period (December-February) of 1982-83 and 1984-85 following a pilot study in January and February of 1980. In addition to intensive observation at the farm, sightings of tagged starlings away from the farm were solicited from the public and mapped. For each year of data on individual starlings that used the farm at least once after marking, the expected frequencies of farm occurrence were calculated and compared to observed frequencies. In all 3 years, there was a significant (P \u3c 0.01) heterogeneity among birds in their frequency of farm use. The observed frequencies of daily farm use appeared bimodal suggesting starling subpopulations of frequent versus infrequent farm users. The preponderance of individuals occurred at the farm infrequently. Analysis of starling foraging patterns indicated that frequent farm visitors were also likely to use livestock feed sites more often than infrequent visitors. In 1984-85 the monthly starling turnover at the farm was calculated at 70.3% from December to January and 67.4% from January to February. Data on marked starling sightings away from the farm indicated that these individuals only moved a median distance of only 2.7 km from the farm suggesting a strong fidelity to their foraging area near the farm. The management implications of these data are discussed relative to integrated strategies of starling damage reduction at livestock farms in the southeastern United States
Optimal Duration for Continuation of Statin Therapy in Bacteremic Patients
Background: Evidence suggests statins may improve survival in patients with bloodstream infections. However, there is no consensus on optimal timing and duration of exposure.
Objectives: To quantify statin therapy duration associated with decreased mortality in bacteremic statin users.
Methods: We conducted a case-control study using OptumClinformatics™ with matched Premier hospital data (1 October 2009–31 March 2013). Cases who died during the hospitalization were matched 1:1 to survivors on disease risk scores (DRSs). Post-admission statin therapy duration was evaluated in patients with at least 90 days of pre-admission continuous statin use. Classification and regression tree (CART) analysis was conducted to identify the optimal duration of statin continuation which provided the lowest inpatient mortality. Logistic regression was used to calculate the odds of mortality.
Results: We included 58 DRS matched pairs of cases and controls: 47 patients (41%) continued statin therapy during the hospital admission, 15 (32%) cases and 32 (68%) controls. The CART analysis partitioned the continuation of statin therapy at ⩾2 days, representing lower mortality for patients who continued statins for 2 days or more and higher mortality for patients who did not continue or remained on statins for only 1 day. Inpatient mortality was 76% lower among those with at least 2 days of continued statin use (odds ratio 0.24, 95% confidence interval 0.11–0.55)
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