# Statistics charts

Teachers can now add statistical graphs to a short-answer question type and ask students to answer by interacting with the dynamic graph. You need to select the *Statistics charts* answer type for drawing answers involving statistic content.

By default, the bar chart option is selected, but the following statistical representations are available: bar chart, line chart and pie chart. All statistical charts designed within WirisQuizzes are interactive and customizable, and our software system automatically evaluates assessments with graphical statistical questions.

## Bar charts

A bar chart is a diagram in which the numerical values of variables are represented by the height or length of lines or rectangles of equal width. This type of graphical representation is now supported by WirisQuizzes Instructors can now create dynamic bar charts as initial content and ask the students to answer questions by interacting with the chart.

### Bar chart toolbar

You will now be able to add and edit bars but also packs to each bar.

#### Vertical and horizontal orientation

Alter the orientation of your bar graph, from vertical to horizontal.

#### Add new bar packs

With the add packs button, you will be able to add as many packs of bars as you wish and label them individually with the tag you consider.

#### Add groups to bar packs

With the add groups button, you will be able to add as many groups as you wish to the bar packs. These groups will automatically appear in different colours.

#### Groups positioning

Alter the positioning of your bar graph groups, from stacked to grouped.

#### Delete groups

Delete a group by clicking on delete group on the lower toolbar menu. This option does not delete packs of bars.

#### Delete bar packs

Delete an entire bar pack by clicking on the delete pack button on the lower toolbar menu. This option will also delete all packs included in the bar group.

## Line charts

A line chart or line plot or line graph or curve chart displays information as a series of data points called 'markers' connected by straight line segments. It's a primary type of chart typical in many fields. This type of graphical representation is now supported by WirisQuizzes Instructors can now create dynamic line charts as initial content and ask the students to answer questions by interacting with the chart.

### Line chart toolbar

You will now be able to add and edit lines, but also line points.

#### Vertical and horizontal orientation

Alter the orientation of your line graph, from vertical to horizontal, with the orientation button.

#### Add group of points

With the add group of points, you will be able to add as many groups of points as you wish within the same lines you’ve established and label them individually with the tag you consider.

#### Add lines

With the add lines, you will be able to add as many lines as you wish to the line groups. With the add line button, you’ll add as many group points as established previously in the other lines.

#### Delete lines

Delete a full line of points by clicking on the delete line button on the lower toolbar menu. This option will not delete a full group of points/labels.

#### Delete group of points

Delete a group of points by clicking on the delete points button on the lower toolbar menu. This option will delete the full group of points, hence the entire label.

## Pie charts

A pie chart is a circular statistical graphic divided into slices to illustrate numerical proportion. In a pie chart, the arc length of each piece is proportional to the quantity it represents. This type of graphical representation is now supported by WirisQuizzes Instructors can now create dynamic pie charts as initial content and ask the students by interacting with the chart.

### Pie chart toolbar

You will now be able to add and edit pie sections.

#### Add new pieces

With the add piece button, you will be able to add as many pie pieces as you wish within the same pie and label each pie piece individually with the tag you consider.

#### Visualize in 2D or 3D

With the 2D/3D button, you will be able to visualize your pie chart either in 2D or 3D.

#### Delete pieces

Delete a piece of the pie chart by clicking on the delete pie button on the lower toolbar menu.

## Input options

In the *Input options* screen, you can control how the *toolbar* provided to the students is displayed and the offered *auxiliary input*. This section will be different depending on the selected statistic chart, but we will only show it for the *bar charts* case as the differences are minimal.

### Customize toolbar

Sometimes, we may not provide the student with all the graph resources. In the *Customize toolbar* section, you can define which will be shown in the student's graph by simply checking or unchecking the corresponding box. They are all selected by default.

The graph resources are divided into five sections: toolbar, menu, floating, contextual (elements), and contextual (labels). You can fully or partially disable them as in the generic plotter.

### Answer input method

Here, you can choose what kind of additional entry you want to offer to the students.

There are three options:

**Display auxiliary CalcMe**: You can supply your students with our online calculator while answering the question and set initial content for the calculator if desired. Keep in mind that the calculator can do a lot more than numerical computations!**Display auxiliary text field**: You can provide your students with a text editor to make them include the reasoning they have followed to answer the question. For more details, see this page: Auxiliary input.**Don't show auxiliary input**: Don't show the additional CalcMe calculator nor the auxiliary text editor in the input field for the student's answer.

## Validation options

The validation options field allows to define us how we want to evaluate the student's answer. This section is divided into two sections explained below.

### Elements

The *Elements* subsection is thought to select the elements in answer to be evaluated. By default, all the elements will be taken into account, and they will have to match the student's answer to be graded correctly.

On the other hand, it's also possible to distribute the grade among those selected elements if we want to consider partial grading.

### Criteria

The *Criteria* subsection is thought to set the amount of error allowed between the student's answer and the correct answer. Moreover, it's also possible to consider some additional properties explained below.

**Prohibit superfluous elements in the student answer**: There can't be more elements in the student answer than in the correct answer.

## Example: Election results

Imagine creating a question asking to represent, given the results of an election for the delegate of the class, the corresponding pie chart. To do so, we have to start defining the initial content. You need to delete two chart pieces and modify the label of the remaining ones to fit with the related students. Besides, you may be interested in setting the initial values to one.

Once we have defined the initial content, we must move on to the *Correct answer* field and modify the pieces accordingly. To start, you can use the *Copy from initial content* option.

Then, we need to define which elements we want the students to use to answer. As we only want them to modify the size of the pieces, we may disable the other options.

Finally, we have to define the validation properties that we want to consider to correctly grade the students' answers. We can require all elements to be correct to grade the question properly or we can distribute the grade accordingly.

We can preview the question by clicking the *Test this question*. Thus, we can verify if it's working as we expected.