91影视

The article 鈥渙rigin of Precambrian iron formations鈥�(Econ,Geology,1964;1025-1057)reports the following data on total Fe for four types of iron formation\((1 = carbonate,\,2 = silicate,\,3 = magnetite,\,4 = hematite).\)

\(\begin{aligned}{l}1:\,\,\,20.5\,\,\,\,\,\\\,\,\,\,\,\,25.2\\2:26.3\\\,\,\,\,\,\,34.0\\3:29.5\\\,\,\,\,\,\,\,26.2\\4:36.5\\\,\,\,\,\,\,33.1\end{aligned}\)\(\begin{aligned}{l}28.1\\25.3\\24.0\\17.1\\34.0\\29.9\\44.2\\34.1\end{aligned}\) \(\begin{aligned}{l}27.8\\27.1\\26.2\\26.8\\27.5\\29.5\\34.1\\32.9\end{aligned}\) \(\begin{aligned}{l}27.0\\20.5\\20.2\\23.7\\29.4\\30.0\\30.3\\36.3\end{aligned}\) \(\begin{aligned}{l}28.0\\31.3\\23.7\\24.9\\27.9\\35.6\\31.4\\25.5\end{aligned}\)

Carry out analysis of variance F test at significance level \(.01,\) and summarize the results in an ANOVA table.

An experiment was carried out to compare electrical resitivity for six different low-permeability concrete bridge deck mixtures. There were \(26\)measurements on concrete cylinders for each mixture; these were obtained days \(28\)after casting.The entries in the accompanying ANOVA table are based on information in the article 鈥淚n-place Resitivity of Bridge Deck Concrete Mixtures鈥�(ACI Matrerials j.,2009: 114-122).Fill in the remaining entries and test appropriate hypothese.

A study of the properties of mental plate 鈥揷onnected trusses used for roof support (鈥淢odeling joints made with Light-Gauge metal connector plates,鈥� Forest products J., 1979:39-44) yielded the following observations on axial-stiffness index(kips/in.) for plate lengths \(4,6,8.10,12\)in:

\(\begin{aligned}{l}4:309.2\\6:402.1\\8:392.4\\10:346.7\\12:407.4\end{aligned}\) \(\begin{aligned}{l}409.5\\347.2\\366.2\\452.9\\441.8\end{aligned}\) \(\begin{aligned}{l}311.0\\361.0\\351.0\\461.4\\419.9\end{aligned}\) \(\begin{aligned}{l}326.5\\404.5\\357.1\\433.1\\410.7\end{aligned}\) \(\begin{aligned}{l}316.8\\331.0\\409.9\\410.6\\473.4\end{aligned}\) \(\begin{aligned}{l}349.8\\348.9\\367.3\\384.2\\441.2\end{aligned}\) \(\begin{aligned}{l}309.7\\381.7\\382.0\\362.6\\465.8\end{aligned}\)

Does variation in plate length have any effect on true average axial stiffness? state and test the relevant hypotheses using analysis of variance with Display your results in an ANOVA table.(Hint : \({\sum x ^2}_{ij.} = 5,241,420.79.)\)

Six samples of each of four types of cereal grain grown in a certain region were analyzed to determine thiamin content, resulting in the following data \((\mu g/g):\)

Wheat \(5.2\) \(4.5\) \(6.0\) \(6.1\) \(6.7\) \(5.8\)

Barley \(6.5\) \(8.0\) \(6.1\) \(7.5\) \(5.9\) \(5.6\)

Maize \(5.8\) \(4.7\) \(6.4\) \(4.9\) \(6.0\) \(5.2\)

Oats \(8.3\) \(6.1\) \(7.8\) \(7.0\) \(5.5\) \(7.2\)

Does this data suggest that at least two of the grains differ with respect to true average thiamin content? Use a level \(\alpha = .05\)