## Overview

You will take the statistics and calculus diagnostic exams in the summer prior to matriculating or during orientation.

Obtaining passing scores on the diagnostic exam is required for enrollment in many courses in the Nicholas School. For example, a frequently required course that necessitates passing the statistics diagnostic is ENVIRON 710 Applied Statistical Modeling for Environmental Management. Classes such as ENVIRON 520 & 521 Resource Environmental Economics I & II require passing scores on the calculus diagnostic exam.

### Statistics & Calculus Prerequisite Deficiencies

Students must show proof of completion of prerequisite level courses before they are permitted to take the diagnostic exams. If you have not had statistics/calculus previously, or were notified by the NSOE Registrar that you have not satisfied the prerequisite, you must take an introductory statistics/calculus course for graded credit (although this credit will not count toward the 48 hours required for the professional program).

If you are not qualified to take the exam(s) in year one, you will have another chance in year two during the summer between the first and second year of study. In the meantime, take the coursework you need to enhance your preparation.

## Statistics Diagnostic Exam

## Exam Prep for the Stats Diagnostic

- We have created a Nicholas statistics review site to assist you in review for the statistics diagnostic.

## Expectations for Statistics Experience

Upper-level statistics courses at Duke, such as Applied Data Analysis (ENVIRON 710, fall), assume mastery of the topics in prerequisite-level statistics. The topics from prerequisite-level statistics that you need include:

- data and descriptive statistics (mean, variance, etc.);
- probability, sampling and distributions;
- sampling concepts and methods (sample size calculations, etc.);
- elements of experimental design (randomization);
- point and interval estimation (confidence intervals), and elements of hypothesis testing;
- paired samples and simple linear regression and correlation.

### ENVIROn 710: Applied Data Analysis

Most students are advised to begin their statistics study at Duke by taking ENVIRON 710, Applied Data Analysis for Environmental Science (designed specifically for MEMs), which serves as a prerequisite to additional statistics courses as well as other upper-level courses such as ENVIRON 850, Program Evaluation. Enrollment in ENVIRON 710 depends on successful completion of the school-wide statistics prerequisite and adequate performance on the statistics diagnostic exam. Statistics (ENVIRON 710) at the Nicholas School is taught in two versions:

- One using the Stata software package that may be of more use to students in the social science areas such as EEP and EE;
- Another using the R (The R Project for Statistical Computing) software package that is more useful to students in the resource science areas such as ESC.

Typically, both versions are taught in the fall semester though there could be variations from year to year. Regardless, it is anticipated that both versions will be offered each year.

## Scores

The Nicholas School statistics diagnostic exam is used to identify student preparation in statistics, with emphasis on those students scoring at the lowest and highest ends of the scale.

- Students entering the Nicholas School in program areas requiring ENVIRON 710 who score in the lower end on the statistics diagnostic exam are required to re-test after either self-study or enrollment in or audit of a remedial course. Students are allowed to retest once. We expect to find very few students in the lower end.
- Students taking ENVIRON 710 who score in the lower part of the middle range may be required to participate in a study group that will provide extra help in statistics, while being permitted to enroll in ENVIRON 710; see instructor for details.

If a student performed extremely well on the diagnostic and has had advanced statistical courses (e.g., multiple regression and generalized linear models), a more advanced statistics course may be considered as a replacement for ENVIRON 710. This replacement must be approved by the student's program chair. Very few students will fall at this highest end of the scale so the majority of entering students will plan on taking ENVIRON 710.

## Calculus Diagnostic Exam

## Expectations for Calculus Experience

Statistics courses and some Nicholas School courses may make use of a variety of calculus topics. These include:

- Algebra (Graphing linear equations, Solving systems of linear equations);
- Functions (Characteristics of Functions in one variable, Logarithmic functions, Exponential functions);
- Calculus of One Variable (Derivatives, Definite and Indefinite Integrals);
- Calculus of More than One Variable (Partial Derivatives, Total Derivatives);
- First-Order Differential Equations (Discrete and continuous time, Rates of decay, Initial conditions).

Most of these are covered in pre-calculus and first-semester calculus courses.

How much calculus you need depends partly on what subjects you want to emphasize here at the Nicholas School; economics, water and air modeling, population ecology, and other kinds of quantitative analysis will put more demands on your math background. In addition, some courses that do not use calculus methods per se do make use of the kind of abstract reasoning that studying calculus helps to develop. Courses commonly taken by Nicholas School professional students will assume that students understand the material on the diagnostic exam; so, if you found that difficult, some review is needed.

If you have not had the calculus prerequisite, you must complete the prerequisite and pass the calculus diagnostic exam first before enrolling in a course at the Nicholas School requiring calculus. The prerequisite level course will not count toward your 48 units for graduation.

## Scores

If you have had calculus, but aren't sure if you have a good enough grip on it, be guided by the recommendation on the diagnostic exam.

**If your score was between 40 and 70**, your knowledge of calculus is not where it should be, and you should consider one of these paths:- Take for credit (but, not towards the 48 units in the professional program) a calculus course;
- Audit (with permission of the instructor) such a course; or
- Study on your own; for example, if you need to review calculus, but do not necessarily need to retake a course, here is a web-based course that could be used to structure your review: http://www.math.temple.edu/~cow/.
- The best choice may depend partly on whether you want to have access to more quantitative subjects here at the Nicholas School.

**If you score below 40**, we urge you to take an introductory calculus class to provide a solid basis for your studies here at the Nicholas School.

## Exam Results

Exams are graded as quickly as possible and results are emailed to faculty instructors and advisors, so that you can use them for course placement decisions before you complete your registration.

Students failing the diagnostic exams may need additional preparation before they are permitted to enroll in graduate level courses requiring a passing score on the diagnostic. In all cases, students should plan to work with either their academic coursework advisor or program chair to make course selections.

## Related Policies

- Statement of Prerequisite Coursework
- Requirements for taking courses to fulfill prerequisites
- Course options for fulfilling prerequisites

(Duke & Inter-Institutional) - Prerequisite Enrollment Notification Form