Off on a Tangent
A Fortnightly Electronic Newsletter from the Hope College Department of Mathematics
 April 13, 2018 Vol. 16, No. 13

Colloquium: Predicting farm incomes in Uganda

Title: Predicting farm incomes in Uganda---Linear, Logistic, LASSO, and beyond
Speaker: Dr. Yew Ming Koh, Hope College
Time: Tuesday, April 17 at 4:00 pm
Place:  VanderWerf 102
A study on farming practices and farm characteristics was carried out in three sub-counties of Kibaale District in Uganda. Using techniques from Statistical Learning, we identify salient features of these farms which are most useful for predicting farm incomes. We discuss the various models used, methods for comparing their prediction accuracy and interpretability, and conclude with a list of levels of features which lead to the highest predicted likelihood of high farm incomes.

Colloquium: Analyzing ranking data

Title: Analyzing ranking data
Speaker: Dr. Martha Precup, Northwestern University
Time: Thursday, April 26 at 4:00 pm
Place:  VanderWerf 102
Suppose you are given data in which consumers were asked to pick their two favorite restaurants from a list of 5.  How can you analyze this information?  In this talk, we will use linear algebra to discern the effects of any one choice on the overall results.  Our methods will use important tools from representation theory called Young tableaux and can be applied to any kind of partial ranking data.

Students participate in the Lower Michigan Mathematics Competition

Seven students (Front row:  Jarrod Devette, Emily Marino, Kimberly Breyfogle.  Back row:  Calvin Gentry, Leah Krudy, Richie Frost, Dane Linsky) traveled to Hillsdale College on Saturday, April 7 to compete in the Lower Michigan Mathematics Competition along with many other teams from a number of other Michigan colleges and universities. They reportedly had a good time and the trip involved donuts, ice cream, show tunes, as well as a little mathematics.

The results should be announced later this month. To view the problems the students worked on click here.

Problem Solvers of the Fortnight

In our last problem of the fortnight we had the following:

To decorate my scrapbook, I cut a 4-inch wide parallelogram out of a square piece of  paper as shown in the diagram on the left.  Surprisingly enough, the parallelogram and each of the two leftover pieces of paper all had exactly the same area!  What are the exact dimensions of the original square?

Congratulations to the following who correctly determined the correct dimensions: Samuel Allbritten, Anna Carlson, Carolyn Cooper, Jordan Corstange, Adair Cutler, Christian Forester, Brandon Fuller, Ce Gao, Calvin Gentry, Hunter Giewswin, Mason Humphrey, Elizabeth Inthisane, Philip LaPorte, Kachikwu Nwike, Zheng Qu, Madeline Stanton, Caleb Stuckey, Fangtao Wang, and Yizhe Zhang

Problem of the Fortnight

Consider the graph of y = 5x - 7x3 in the first quadrant shown in the figure.  What is the constant k so that the areas of the two shaded regions are equal when sliced by the line y = k?

Write your solution (showing all relevant work) and drop it in the Problem of the Fortnight slot outside Professor Mark Pearson's office (VWF 212) by 3:00 p.m. on Friday, April 20.  As always, be sure to include your name and the name(s) of your math professor(s) -- e.g. 
Nadia Geddit, Dr. Eureka Garlic  --- on your solution.

Little darling, it's been a long cold lonely winter
Little darling, it feels like years since it's been here
Here comes the sun
Here comes the sun, and I say
It's all right

~George Harrison

(Okay, this is just hopeful thinking!)

Off on a Tangent