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Showing posts from May, 2016

Linear regressions and confidence intervals

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My one remaining use of Gnumeric had been the regression statistical function which produced confidence intervals for slopes and intercepts along with p-values against a null hypothesis that either one was zero. With Gnumeric having opted to be "Linux only" in 2014, I wanted to have some of those same capabilities in cross-platform LibreOffice.org. Although the LibreOffice 5 includes a statistics add-in by default with a regression option, that option did not produce the values I sought.

The core to the solution was on board LibreOffice all along. The LINEST function, entered as an array formula produces the values necessary to generate confidence intervals. 



When entered into a two by five array of cells as an array formula, the results of the function generate standard error values for the slope and intercept. The values generated by LINEST can then be used to feed other functions.




Values such as t-critical, the margin of error, bounds on the confidence intervals, an…

Assessing learning in physical science

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SC 130 Physical Science proposes to serve two institutional learning outcomes (ILO) through four general education program learning outcomes (GE PLO) addressed by four course level student learning outcomes (CLO). Not listed are proposed specific student learning outcomes that in turn serve the course level learning outcomes.  This report assesses learning under the proposed course level learning outcomes which in turn supports program and institutional learning outcomes.

ILO 8. Quantitative Reasoning: ability to reason and solve quantitative problems from a wide array of authentic contexts and everyday life situations; comprehends and can create sophisticated arguments supported by quantitative evidence and can clearly communicate those arguments in a variety of formats.

GE PLO SC 130 CLO 3.5 Perform experiments that use scientific methods as part of the inquiry process. 1. Explore physical science systems through experimentally based laboratories using scientific methodologies 3…

Assessing Learning in Ethnobotany

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SC/SS 115 Ethnobotany proposes to serve four program learning outcomes through three course level outcomes. The course serves learning outcomes in general education, the Micronesian studies program, and the Agriculture and Natural Resources program.

PLO SC/SS 115 CLO GE 3.4 Define and explain scientific concepts, principles, and theories of a field of science. 1. Identify local plants, their reproductive strategies, and morphology. GE 4.2 Demonstrate knowledge of the cultural issues of a person’s own culture and other cultures.

MSP 2 Demonstrate proficiency in the geographical, historical, and cultural literacy of the Micronesian region. 2. Communicate and describe the cultural use of local plants for healing, as food, as raw materials, and in traditional social contexts. ANR 2 Demonstrate basic competencies in the management of land resources and food production. 3. Demonstrate basic field work competencies related to management of culturally useful plant resources and foods.
CLO 1

I…

Assessing learning in introductory statistics

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MS 150 Introduction to Statistics has utilized an outline based in part on the 2007 Guidelines for Assessment and Instruction in Statistics Education (GAISE), the spring 2016 draft GAISE update, and the ongoing effort at the college to incorporate authentic assessment in courses. The three course level student learning outcomes currently guiding MS 150 Introduction to Statistics are:
Perform basic statistical calculations for a single variable up to and including graphical analysis, confidence intervals, hypothesis testing against an expected value, and testing two samples for a difference of means.Perform basic statistical calculations for paired correlated variables.Engage in data exploration and analysis using appropriate statistical techniques including numeric calculations, graphical approaches, and tests. The first two outcomes involve basic calculation capabilities of the students and are assessed via an item analysis of the final examination (original was a test inside Schoolog…

Hints that partial attendance is better than none

Students arriving late for class, especially early morning classes, is not uncommon at the college where I teach. There are a variety of factors that contribute to this, all of which are discussed perpetually by faculty. Each new faculty member discovers anew the issue of late arrivals. Some faculty in the past have gone as far as locking the class room doors. Others, intentionally or unintentionally, may embarrass the late arriving student.

Late arrivals can be disruptive to a class, especially if group work is the plan for the day. How one handles late arrivals also determines the impact those late arrivals may or may not have.

While rummaging through attendance and late arrival data looking for signals, a practice strongly discouraged by the statistical test community, I noticed that absences appeared to be correlated to weaker performance in class while late arrival - partial attendances if you will - were not correlated to performance.

The course examined was MS 150 Statistics co…

Ethnobotany review for authentic assessment final

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Years ago a researcher arrived on Pohnpei who I had been led to believe had expertise in tropical plants. Upon arrival, the researcher asked for a tour of the rather small if not completely pathetic ethnobotanical garden my class had been tinkering around in for a few years. I was excited by the chance to get come help in identifying plants I could not identify.

As we walked down to the garden we passed Terminalia catappa, our local dipwopw tree also known as a seaside almond. The researcher looked at the tree and gave some Latin binomial I did not recognize. I asked if maybe the tree was not Terminalia catappa, and the researcher agreed that the tree could be T. catappa. For the first few plants, plants I already knew well, the researcher was citing Latin-sounding names that were unconnected to the plants. When I would suggest the name I knew, the researcher would agree with words to the effect, "Oh, yes, of course."  Eventually the researcher fell silent. I already knew I …