Question

In: Statistics and Probability

please use R studio to answer the following questions 1. An eductional theorist collects behavioural data...

please use R studio to answer the following questions

1. An eductional theorist collects behavioural data from two groups of children in an early childhood center. She measures how much time the children are active (e.g. running or swinging on the monkey bars) in minutes. The first group of children are encouraged to run about and as such are expected to be active; the second group is encouraged to sit still and paint, and are expected to be less active.

The first group has total activity time of: c(76.8, 76.5, 71.2, 57.2, 65.9, 66.1)

And the group has strength ratings of: c(52.4, 62, 75.4, 62.8, 63.6, 64.1, 83.5, 61.3, 72.2, 50.3, 82.4 )

Is there evidence that the first group is actually more active than the second?

(a) State a sensible null hypothesis

(b) State the precise definition of p-value and explain what “more extreme” means in this context

(c) Is a one-sided or two-sided test needed? justify

(d) Perform a student t-test using R and interpret

Expert Solution

a) There is no significant difference between mean Total active time of first group and second group.

b) p value is probability of null hypothesis is correct. in case of right tailed test the more extreme is as total active time for first group is greater than group two.

c)one sided (upper tailed) test is needed

d)from the results in r studio,

p value is greater than 0.05( level of significance).

Therefore we accept null hypothesis at 5% level of significance.

I.e there is no significant difference between mean Total active time of first group and second group.

orchestra answered 1 year ago

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