teOfBirth) has been changed from Ohio to Indiana
#(state of birth of Jim Davis, the creator of the cartoon &quot;Garfield&quot;).
pd$stateOfBirth[pd$firstName == &quot;James&quot; &amp; pd$lastName == &quot;Garfield&quot;] &lt;- &quot;Ohio&quot;

#We fix the following mistake:
#Calvin Goolidge has had his first name changed to &quot;Hobbes&quot; (firstName).
pd$firstName[pd$firstName == &quot;Hobbes&quot;] &lt;- &quot;Calvin&quot;

#We fix the following mistake:
#Eisenhower appears twice in the dataset, one