Data Explorer Troubleshooting Page

  1. Accessing the Data Explorer
  2. Security and privacy
  3. Formatting your files for upload
  4. Problems with uploading your files
  5. Problems with mapping your files
  6. Modifying data you’ve already uploaded
  7. Problems with visualizing your data

Accessing the Data Explorer

  • Go to
  • Click “Login or register”
  • Follow the instructions to register and get verified as an educator
  • Click “upload” and follow the instructions

If you don’t see the “upload” button, it’s either because you are not logged in, or because your account does not yet have permission to access the Data Explorer.

Security and privacy

Read our security FAQ. Still have questions? Contact us.

Formatting your files for upload

  • Supported file types include: .xls, .xlsx, .csv
    • We currently do not support .xlsm (Excel macros) or Excel files that are password protected.  Please extract the sheets from these files as a .csv or normal Excel file and remove any password protection.
  • Include a header row telling us what's in each column
  • Include only individual student responses for each question below the header row
  • At least one column must be student IDs or Names for pre-post matching
  • Only one class and one assessment per sheet
  • May contain pre, post, or both in the same sheet

No, there is not. We don't provide a template because the system is designed to read your files in nearly any format you have them in, as long as they meet our basic file requirements. Most users shouldn't have to modify their files at all, though some users will need to make minor adjustments such as adding a header row.

For standard multiple-choice assessments like the FCI, FMCE, BEMA, or CSEM, responses should be in the form A,B,C,... or 1,2,3,... or 0,1,2,... For agree/disagree assessments like the CLASS or MPEX, responses should be in the form A,B,C,... or 1,2,3,... or strongly agree, agree,... or sa, a,...

We can’t take files in this format yet. We recognize that many online systems output data in this format, and are considering adding this feature in the future, but do not currently have funding to do so. If you have a script that converts files in this format to a format that our system can use, please send it to us so we can make it available to other users. If you would like to support the development of this feature, please contact us.

We can’t take files in this format yet. We are considering adding this feature in the future.

We currently can’t take your files unless you gave all the questions on the assessment. We are considering adding this feature in the future. However, we are carefully weighing our users’ desire for this feature with assessment developers’ recommendations that you should give all questions on an assessment.

The Data Explorer looks for a block of student responses in your file, so as long as there is a header row and a block of student responses following this row, we will be able to handle the file. Many of our users have data in Excel scoring templates that contain a lot of extra information, and we can easily process these files.

We are able to handle small gaps in your student data as long as you give a good estimate of how many students the file contains; however, to ensure we find all of your students, please remove any completely blank rows between student data. If there is a student name with blank responses (e.g. a student who left all questions blank), we will exclude that row from analysis but still find the students before and after it. However, if there are completely blank rows (e.g. between matched and unmatched students), we won’t be able to find all the student responses in your file, and will end up using only the responses above or below the blank row.

In the future, we may add the ability for you to tell us not to count these rows, but for now, please remove them. We currently unable to distinguish between rows that are answer keys and rows of students who answered all questions correctly.

In the future, we may add better handling of files without header rows, but for now, we expect a header row with column headings.  If your file doesn't have a header row, we treat the first row of student data as a header row and do not include that student data in our analysis. If the row above the black line on the column mapping page looks like student data, please cancel your upload, add a header row to your file, and start over.

No, you just need to include your students’ names and/or IDs, and we will match them for you.

We ignore all dashes and spaces in the student ID field, so this is not a problem.

No, we ignore capitalization and spaces in the student name field, so this does not need to be consistent between pre and post files.

If you give us only one form of student identifier, such as student ID or name, we will not be able to match students if this identifier is not exactly the same in both the pre-test and post-test file. However, if you give us both student names and IDs, we will use both, so that if the IDs don’t match but the names do (or vice versa), we will still be able to match your students. Users who have previously matched their students by hand find that, if they upload their original unmatched data to the Data Explorer, we can match almost as many students as they did with a lot of painstaking work.

Problems with uploading your files

If you are uploading an Excel or CSV file and we can’t read it, it might be because:

  • It is an invalid file; for example, it might be a tab-separated file (TSV) rather than a true CSV or Excel file. Some online systems, such as WebAssign and LASSO, generate files in which the values are separated by tabs rather than commas, and then add a .csv or .xls extension, even though it isn’t a true .csv or .xls file. One way to fix this is to open your file in Microsoft Excel and go to File->Save as and save it as a CSV (Comma Delimited)(*.csv) file, as an Excel Workbook (.xlsx), or as an Excel 97-2003 Workbook (.xls).
  • It is corrupt. This can sometimes be fixed by opening your file in Excel and following any on screen prompts.

Problems with mapping your files

On the file mappings page, our system guesses what’s in each of your columns based on the content of your header row. Some headers are difficult to guess; however, the system will learn your typical headers. As more files are uploaded, we can use machine learning to guess based on the various headers our users have in their files.

In order to protect your students’ privacy, we don’t preserve anything in your file that might contain identifiable information. Once you click done on the file mappings page, we perform a secure one-way encryption on your students’ names and IDs, and delete the original contents of any columns that you told us not to import. This means that your original file is gone, so we can’t go back to the file mappings page.

As long as the format is the same in both the pre and post file, it doesn’t matter what the format is. We treat the whole field as one value. Because of this, you do need to have names in the same format in both the pre and post file. If one file has student first and last names in separate columns and the other file has them combined into one column, we won’t be able to match them. We may add improved handling of student names in future versions if enough users request it, but so far our handling of student names works for most.

Modifying data you’ve already uploaded

Click on “Your Data” at the top of the page. Scroll down and open “Classes”, “Courses”, “Instructors”, or “Institutions” and click on the edit icon next to the one you want to edit. You can edit the name of any class, course, instructor, or institution, or any of the details about it.

Click on “Your Data” at the top of the page. Under “Assessment Datasets”, click on the action menu next to the one you want to edit. To edit the details about how you gave the assessment, choose “Edit Assessment Details”. To add post-test data to existing pre-test data, choose “Upload Post-test Data”. To add student information such as demographics, choose “Upload Student Information”.

If you imported a file incorrectly, you can replace it by selecting “Replace Data Files” from the action menu on the “Your data” page. Under “Assessment Datasets”. In most cases, replacing your file should be sufficient. If you need to completely delete the dataset, select “Other”. Tell us about your mistake and why you want to delete it.  We will take care of it for you in 1-2 days. We are working on building an automated way to do this, and your feedback helps us in designing that process.

Problems with visualizing your data

Some reasons this might be happening:

  • You didn't select the appropriate answer format. If your file has answer choices coded as numbers, we guess whether the answer format is ABCDE = 01234 or ABCDE = 12345. If we guessed wrong, and you didn't correct us, your students' scores will be a lot lower than they should be. To check which answer format we guessed (and change it if you need to), click on "Your data" and then select "View Summary" from the action menu for the appropriate dataset.
  • You are using a different formula for normalized gain than we are. Normalized gain can be calculated using the average of gains for each student or the gain of average scores for the class. We use the former. If you use the latter, your gains might differ from ours by 5-10%, especially if you have a small class. For students who scored lower on the post-test than the pre-test, we use the normalized change rather than the normalized gain. Learn more about how we calculate normalized gain and normalized change.
  • You are using a different formula for score than we are. Some assessments have special scoring schemes that are more complicated than just adding up the number of correct responses. To see how we calculate the score for a particular assessment, find the assessment in our assessment list, click on the "Resources" tab, and download the implementation guide.
  • We are excluding students you included in your calculations. We calculate normalized gain only for matched students. We exclude students who answered fewer than 2/3 of the questions on the assessment or who incorrectly answered CLASS question 31 (select "agree" if you are paying attention). To check how many students we matched and excluded, click on "Your data" and then select "View Summary" from the action menu for the appropriate dataset.
  • If you've checked all these things and your calculations still don't match ours, please contact us so we can help you figure out why.

We occasionally encounter errors while drawing the visualization.  This can sometimes be fixed by refreshing the page or closing and reopening the browser.  If the error persists, please contact us so we can help.  If you do not encounter an error message but your visualization does not load completely, you may be using an incompatible browser.  For the visualization section of the Data Explorer, we only support up-to-date versions of Firefox, Chrome, Edge, and Safari.

Some browsers do not fully support this feature and may not download the chart or the image downloaded may not be rendered properly. We suggest using the latest version of Chrome or Firefox to use this feature.