IRAhandle_tweets_5.csv contains 4 records with '-1' in the external_author_id column

[ChuliangXiao]

IRAhandle_tweets_5.csv contains 4 records with -1 in the external_author_id column, as follows, -1 replaced with NA,

external_author_id	author	content	region	language	publish_date	harvested_date	following	followers	updates	post_type	account_type	retweet	account_category	new_june_2018	alt_external_id	tweet_id	article_url	tco1_step1	tco2_step1	tco3_step1
NA	FINDDIET	muvva @_SlaYonce Marissa @marissafabrizi Tawnya @sdxNomadMom Happy @HelenFJohnson http://t.co/Z8DHogbMn8 https://t.co/9Fe1weThaC	United States	LANGUAGE UNDEFINED	8/12/2015 11:04	8/12/2015 11:12	3	308	29699	NA	Commercial	0	Commercial	1	NA	6.314209e+17	http://twitter.com/FindDiet/statuses/631420894506713088	https://twitter.com/marissafabrizi_/status/631419756613124096	https://twitter.com/safety/unsafe_link_warning?unsafe_link=http%3A%2F%2FWWW.LOSEFATTIPS.PW%2FTIPS%2FLITERALLY-SAME-WHEN-I-TRY-AND-RUN-TO-LOSE-WEIGHT.ASP	NA
NA	FINDDIET	http://t.co/MKzEwWBPwr Toe @hongtony22 ժɑɾíɑղ @woaahdaare Tara @intowalls Delaney @vandell66 Fattie @FattaySD https://t.co/cQrguxWQtT	United States	LANGUAGE UNDEFINED	8/12/2015 23:08	8/12/2015 23:08	3	331	30648	NA	Commercial	0	Commercial	1	NA	6.316031e+17	http://twitter.com/FindDiet/statuses/631603122641596417	https://twitter.com/ivannvega23/status/631601740173975552	https://twitter.com/safety/unsafe_link_warning?unsafe_link=http%3A%2F%2FWWW.LOSEFATTIPS.PW%2FTIPS%2FGIRLS-WHO-WORKOUT.ASP	NA
NA	FINDDIET	http://t.co/wFGUVzURSM Jay .@Jay_zo Nina .@xxooninaooxx Medeia .@sharifwrites K♛ .@Stcrbuks Jess .@jjeessss81 https://t.co/GOctHrGhiG	United States	LANGUAGE UNDEFINED	8/13/2015 0:18	8/13/2015 0:19	3	334	30756	NA	Commercial	0	Commercial	1	NA	6.316208e+17	http://twitter.com/FindDiet/statuses/631620795354058752	https://twitter.com/xxooninaooxx/status/631620042229215232	https://twitter.com/safety/unsafe_link_warning?unsafe_link=http%3A%2F%2FWWW.LOSEFATTIPS.PW%2FTIPS%2FMY-FAVE-WORKOUT.ASP	NA
NA	FINDDIET	http://t.co/U4DFGCaSEF Davi_hoops @comiclyfe_12 YELLA @ImYellaForeal perelondon @perelondon1 Sharday @whitegalshay https://t.co/7mh7C2GkKE	United States	LANGUAGE UNDEFINED	8/13/2015 6:27	8/13/2015 6:27	3	350	31267	NA	Commercial	0	Commercial	1	NA	6.317136e+17	http://twitter.com/FindDiet/statuses/631713577162805248	https://twitter.com/rainbowsonlou/status/631712761962233856	https://twitter.com/safety/unsafe_link_warning?unsafe_link=http%3A%2F%2FWWW.LOSEFATTIPS.PW%2FTIPS%2FGOOD-WORKOUT-AT-THE-GYM.ASP	NA

[EvanCarroll]

From my perspective, they should just be NULL. Ie., empty, They should certainly not be strings though which is what I filed in #30 . In my fork they're -1, but unquoted if you're trying to pull them in.