# Thread: What test to use with this scenario?

1. ## What test to use with this scenario?

Hi guys,

I hope this is the correct forum, wasn't sure if it needed to go in the Basic Statistics forum.

Here's the problem:

A student is wondering if iPhone usage has increased in his city since 2008. To do so, he performs a 200 person poll and asks what kind of phone they own. The first time he performed the poll, in 2008, 130 people in his poll owned an iPhone, and 70 did not. When he performed the same poll again in 2010, on 200 different people (but still people in his city), he found that 155 people owned an iPhone, whereas 45 people did not.

a.) What Statistical inference test would you use to determine if iPhone usage increased in his city since 2008?
b.) Was there a statistically significant increase in iPhone usage in his city based on his two samples of 200 people?

Alright so first I have to determine if the data is parametric or nonparametric, correct? If so, how would I determine what test to use?

Thanks for any help!

James

2. Have you seen the test for difference in proportions?