Here are Lichtman's 13 criteria -- via his book "Predicting the Next President: The Keys to the White House 2016" and as summarized by WaPo's Peter Stevenson:
1. Party Mandate: After the midterm elections, the incumbent party holds more seats in the US House of Representatives than after the previous midterm elections.
2 Contest: There is no serious contest for the incumbent party nomination.
3. Incumbency: The incumbent party candidate is the sitting president.
4. Third party: There is no significant third party or independent campaign.
5. Short-term economy: The economy is not in recession during the election campaign.
6. Long-term economy: Real per capita economic growth during the term equals or exceeds mean growth during the previous two terms.
7. Policy change: The incumbent administration effects major changes in national policy.
8. Social unrest: There is no sustained social unrest during the term.
9. Scandal: The incumbent administration is untainted by major scandal.
10. Foreign/military failure: The incumbent administration suffers no major failure in foreign or military affairs.
11. Foreign/military success: The incumbent administration achieves a major success in foreign or military affairs.
12. Incumbent charisma: The incumbent party candidate is charismatic or a national hero.
13. Challenger charisma: The challenging party candidate is not charismatic or a national hero.