Having read the information provided my questions in relation to the attached documents would be:
How many immigrants shipped on Liverpool arrived at the USA on1846-1848? (quantitative analysis)
Would you say that the immigrants arrived compose a family? Why? (qualitative analysis)
From the attached documents we might say that there was a wave of immigrants coming from the UK, original from GB and Ireland. Most of them shipped on Liverpool: 35 out of 49. 12 of them were underage, all of them listed by Furlong surname.
Making a quick analysis you can find 7 groups that might be families mainly because they depart from the same port and traveled on the same ship.
Phil (28), U (23) and U (born at sea) arrived in the US on M26th, 1848.
George and William (23), possibly brothers arrived in the US on May 2nd, 1849
Ellen (19)and Margaret (30), possibly daughter and mother, arrived in the US april 17th, 1849
Pat (33), Catherine (33), James (12), Michell (10), Antony (05), Martin (06), Eliza (4) and Mary (born at sea) arrived in the US August 10th, 1848
May (36), Johana (04) and Mary (11moths) arrived in the US on March 27th, 1848. The father of the family might have come separately or might not be part of the family anymore.
Francis (49), U (49), Catherine (26), Johana (23), Ellen (20) and Jas (19) arrived in the US on March 23rd, 1848
Pat (40), Hellen (40) and William (9) arrived in the US on February 24th, 1847. From the information listed on the document, you might say it was the first family on the USA, originally from Ireland, with Furlong surname.