Word Works

Learning through writing at Boise State University

BSU Writing Center & Writing Across the Curriculum

Numbers 102 & 103 - February &March 2000


An effective approach to grading:
Primary Trait Analysis

Though Word Works has in the past published a few pieces that touch on responding to student writing, we have so far said very little about evaluating and grading writing. We have avoided the subject for a number of reasons, the main one involving the uneasy truce teachers must maintain between writing and grading. Many faculty who teach writing or use writing assignments dislike having to figure out grades for student papers: so many papers have such mixtures of strengths and weaknesses they are hard to fit into any grading slot without doing some injustice. Another reason many teachers dislike grading is that grades don't contribute very much to learning. It's true that a grade is a form of feedback, students who take the time to analyze their work when they get it back can learn a lot about why it received the grade it did. But for most students, grades alone are not a very informative way to identify strengths and weaknesses in writing.

One system that is proving to be effective is Primary Trait Analysis (PTA). It is a system of evaluating and grading designed to show students what specific strengths their work exhibits and what weaknesses they need to work on. It is a point system, similar in some ways to other point-based grading systems. The differences are that (1) the point scale is divided into several categories of equal weight, and (2) the points in the scale are linked to specific descriptions of strengths and weaknesses.

PTA is not new. It first became well known from a 1977 article by Richard Lloyd Jones. More recently it has been promoted by Barbara Walvoord and Virginia Johnson Anderson in their 1998 book, Effective Grading. This issue of Word Works is greatly indebted to both these sources, and to a workshop conducted by Walvoord and colleagues from the University of Notre Dame at the 1998 IUPUI Assessment Institute in Indianapolis. The institute was attended by a team sent from BSU to gather information toward developing an assessment program for the Core Curriculum.

What a PTA scale looks like

Because PTA scales tend to be pretty long, we won't show you a complete scale right here. By the time you got through it you might not want to read the rest of what we have to say. We have appended a couple of sample complete scales on pages 4-8. Here is an abbreviated one, three excerpts from a scale devised to evaluate and grade science reports.

Science report--abbreviated example

The complete scale breaks down the parts of the report thus:

    I. Introduction
  1. Provides history and context.
  2. Contains the hypothesis to be tested.

II. Materials and methods

III. Etc. (separate categories for Findings, Discussion, Conclusion, References)

Here is the detailed set of level descriptions from three of the categories. The numbers are points the report can earn in each category, from 4 to 1. The points for all categories are added up and converted to a letter grade.

Introduction A

4 History well researched. Major contributions presented with discrimination and balance. Controversies outlined and weighed.

3 History adequately outlined. Role of major contributions recognized. Relative merit of conflicting opinions somewhat unclear.

2 Historical outline present. Contextual development and relative merit of contributions unrecognized or ragged. Presentation of conflicting ideas absent.

1 Historical outline absent or garbled. Contributions listed as in a diary; consideration of merit absent. Notions of conflicting ideas ignored.

Introduction B

4 Hypothesis clearly recognized or well crafted and elegantly stated in testable form. Hypothesis cleverly embedded in context.

3 Hypothesis recognized or well stated. Contextual connections evident.

2 Hypothesis detectable but may not be stated in testable form. Contextual connections tenuous.

1 Hypothesis undetectable or garbled so as to violate scientific principles. Context absent or ignored.

Materials & Methods B

4 Procedures clear, need no interpretation. Appropriate details present.

3 Procedures easily interpreted. Relevant information dominates.

2 Procedures unclear but interpretable. Irrelevant information interferes.

1 Procedures scrambled. Irrelevant information predominates. Reads more like a bad diary.

How to create a PTA scale

If you glance at the two sample scales on pages 4-8, you may feel daunted. It looks like a lot of work, writing out all those descriptions. But the work is not so hard if it's done in small steps; it doesn't all have to be done at once. The sample scales were developed over a period of time, as the instructors gradually clarified their expectations. Here are some hints for making the project doable, without taking up a huge amount of time.

Scales are works in progress

Treat your PTA scale as an ongoing draft, always in need of more work. As you use it you will find various ways to fine-tune (or completely rethink) the scale. In particular;

Advantages of PTA

A PTA scale offers benefits both for students and instructors. Some of the prominent advantages are: