In: Statistics and Probability
solve using r and
Consider the data birds.txt. A wildlife ecologist measured X1 = Tail length (in millimeters)
and X2 = Wing length (in millimeters) for a sample of n = 45 female hook-billed kites.
(a) Construct both Q-Q plots and histograms from the marginal distributions of tail length
(X1) and wing length (X2). Do these data appear to be normally distributed? Discuss.
(b) Is the bivariate normal distribution a viable population model? Discuss.
(c) Consider the variable, wing length (X2). Construct a 95% confidence interval for the mean wing length for the female birds. Interpret the interval in the context of the problem.
(d) Based on the reported interval in Part(c), a two-sided hypothesis test with H0 : μ2 = 274 mm vs. Ha : μ2 ̸= 274 mm and a significance level of α = 0.05 would reach what decision? Explain the reason behind your decision.
the data file is
Tail Wing 191 284 197 285 208 288 180 273 180 275 188 280 210 283 196 288 191 271 179 257 208 289 202 285 200 272 192 282 199 280 186 266 197 285 201 295 190 282 209 305 187 285 207 297 178 268 202 271 205 285 190 280 189 277 211 310 216 305 189 274 173 271 194 280 198 300 180 272 190 292 191 286 196 285 207 286 209 303 179 261 186 262 174 245 181 250 189 262 188 258