<award>

Attribute Examples Part 1

The following examples illustrate use of the <award> tag attributes.

Attribute Example: credit

<p><em>For the following question, first enter <m>\frac{4}{8}</m> and 
then <m>\frac{1}{2}</m>.</em></p>
 
<p>Question: Simplify <m>\frac{8}{16}</m>
<answer symbolicEquality>
  <award>1/2</award>
  <award credit="0.5">4/8</award>
</answer>
</p>

By default, a matched <award> will give full credit of 1. Specify a smaller value of the credit attribute cause the <award> to give partial credit.

Attribute Example: matchPartial

When the matchPartial attribute is applied, an automated partial credit evaluation will be attempted, potentially giving credit between 0 and 1. Without the matchPartial attribute, the response must be completely correct before it receives credit.

The automated partial credit algorithm will attempt to break up logical conditions into pieces and look separately at components of vectors.

For comparison of vectors, the attributes matchByExactPositions and unorderedCompare influence the partial credit algorithm.

Attribute Example: symbolicEquality

Note that you cannot repeat the original expression in the first question, and you cannot commute the terms in the second question.

For answer validation that is more liberal (but still stricter than the default numerical checker), combine symbolicEquality with the simplifyOnCompare and expandOnCompare attributes.

Attribute Example: symbolicEquality with simplifyOnCompare

Specifying the symbolicEquality attribute switches to a symbolic answer-checker that demands exact syntatical equality. The symbolic equality can be relaxed with the simplifyOnCompare attribute.

The simplifyOnCompare attribute has four options:

• simplifyOnCompare="none": the default value of demanding exact equality.
• simplifyOnCompare="full" (or simply simplifyOnCompare by itself): apply currently available simplification routines before checking. Does not include expanding factored expressions.
• simplifyOnCompare="numbers": simplify numerical expressions like 1+2 but not algebraic expressions. Permute terms and factors into a canonical order before checking equality.
• simplifyOnCompare="numbersPreserveOrder": simplify numbers but without permuting terms or factors.

To include expansion of factored expressions, you can add the expandOnCompare attribute.

Attribute Example: symbolicEquality with expandOnCompare

The default comparison is a numerical answer-checker with a liberal definition of equality. Specifying the symbolicEquality attribute switches to a symbolic answer-checker that demands exact syntatical equality. The symbolic equality can be relaxed with the simplifyOnCompare attribute. To expand factor expressions prior to comparison, you should also include the expandOnCompare attribute.

Attribute Example: unorderedCompare and unordered

When multiple values are compared within a single <award> tag, the default behavior is to match the order of the sequenced values. If order is irrelevant, use the unorderedCompare attribute.

unorderedCompare can be used with list components (e.g., <mathList>, <numberList>, and <textList>) as well as the <math> component containing a list (e.g, 1,2,3), tuple (e.g., (1,2,3)) or array (e.g., [1,2,3]).

Alternatively, and for more control over what is ordered, one can add the unordered attribute directly to a list component or a <math>, which will cause an unordered comparison to be used when comparing it to anything else.