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Assessment is necessary, but difficult, in statistics education. Multiple choice assessments are common, particularly for research purposes. Open-ended assessments may be more adept at revealing student understanding, but ensuring their validity can be difficult. The study presented here examines differences in student descriptions of histograms for different question prompts and scenarios in order to understand how best to ask such questions in research and teaching situations. The results show that different ways of asking students to describe histograms and different scenarios and shapes of histograms lead to systematic differences in student descriptions of histograms. The paper concludes with suggestions for phrasing questions, both for research and classroom assessment, and provides directions for future research based on our results.

Individual person fit analyses provide important information regarding the validity of test score inferences for an "individual" test taker. In this study, we use data from an undergraduate statistics test (N = 1135) to illustrate a two-step method that researchers and practitioners can use to examine individual person fit. First, person fit is examined numerically with several indices based on the Rasch model (i.e., Infit, Outfit, and Between-Subset statistics). Second, person "mis"fit is presented graphically with person response functions, and these person response functions are interpreted using a heuristic. Individual person fit analysis holds promise for improving score interpretation in that it may detect potential threats to validity of score inferences for some test takers. Individual person fit analysis may also highlight particular subsets of items (on which a test taker performs unexpectedly) that can be used to further contextualize her or his test performance.

Recent stream restoration approaches, such as Stage 0 restoration, aim to restore natural processes to regain lost ecosystem functions, but project implementation can also represent a reach‐scale disturbance. Assumed outcomes of these restoration actions, like greater biological productivity, are rarely evaluated. In this study, we examined the short‐term effects of Stage 0 floodplain restoration on the secondary production of aquatic macroinvertebrate communities in the South Fork McKenzie River, Oregon, 1–2 years following project implementation. We seasonally sampled macroinvertebrates from benthic and submerged wood surfaces in the restored reach, and two unrestored reference reaches located upstream, to estimate annual secondary production. Macroinvertebrate production estimates were 3× lower on a per‐meter‐squared basis in the restored reach than in the upstream unrestored reference reaches (9764 vs. 29,636 mg DM/m2/yr). However, because there was 4.5‐times greater wetted area available in the restored reach, overall macroinvertebrate production per unit of valley length was 3.4× higher in the restored reach than in unrestored reference reaches (2744 vs. 802 kg DM/km). Additionally, the mosaic of aquatic habitats created via restoration (main‐channel, side‐channel, and wetted forest habitats) supported a diversity of macroinvertebrate assemblages both within and among reaches. Our findings suggest Stage 0 project implementation, which can include dewatering and filling incised channels, may reduce aquatic macroinvertebrate production on a per‐unit‐area basis for at least 1 or 2 years following restoration. However, this short‐term disturbance effect may be offset by channel aggradation and widening, which can provide a more wetted area for macroinvertebrate production and may support greater macroinvertebrate community diversity. Future studies are needed to examine the longer term (2–10 years) aquatic macroinvertebrate response to Stage 0 restoration, and the impacts of shifting resource availability on stream fishes. [ABSTRACT FROM AUTHOR]