Suppose that the weights (in kgs) of six months old babies, monitored at a healthcare facility, have
N ( ΞΌ , Ο 2 ) N(\mu, \sigma^2) N ( ΞΌ , Ο 2 ) distribution, where
ΞΌ β R \mu \in \mathbb{R} ΞΌ β R and
Ο > 0 \sigma > 0 Ο > 0 are unknown parameters. Let
X 1 , X 2 , β¦ , X 9 X_1, X_2, \ldots, X_9 X 1 β , X 2 β , β¦ , X 9 β be a random sample of the weights of such babies. Let
X βΎ = 1 9 β i = 1 9 X i \overline{X} = \frac{1}{9} \sum_{i=1}^{9} X_i X = 9 1 β β i = 1 9 β X i β ,
S = 1 8 β i = 1 9 ( X i β X βΎ ) 2 S = \sqrt{\frac{1}{8} \sum_{i=1}^{9} (X_i - \overline{X})^2} S = 8 1 β β i = 1 9 β ( X i β β X ) 2 β and let a 95% confidence interval for
ΞΌ \mu ΞΌ based on
t t t -distribution be of the form
( X βΎ β h ( S ) , X βΎ + h ( S ) ) (\overline{X} - h(S), \overline{X} + h(S)) ( X β h ( S ) , X + h ( S )) , for an appropriate function
h h h of random variable
S S S . If the observed values of
X βΎ \overline{X} X and
S 2 S^2 S 2 are 9 and 9.5, respectively, then the width of the confidence interval is equal to __________ (round off to 2 decimal places) (You may use
t 9 , 0.025 = 2.262 , t 8 , 0.025 = 2.306 , t 9 , 0.05 = 1.833 , t 8 , 0.05 = 1.86 t_{9,0.025} = 2.262, t_{8,0.025} = 2.306, t_{9,0.05} = 1.833, t_{8,0.05} = 1.86 t 9 , 0.025 β = 2.262 , t 8 , 0.025 β = 2.306 , t 9 , 0.05 β = 1.833 , t 8 , 0.05 β = 1.86 ).