The table below displays data from an experiment focused on nutrient addition and plant diversity. The explanatory variable is the response variable is Number of Number of Plot # Nutrients Added Plant Species 36 2 36 32 4 34 33 3 30 20 8 23 4 21 10 4 16

Trace metals in drinking water affect the flavor and an unusually high concentration can pose a health hazard. Ten pairs of data were taken measuring zinc concentration in bottom water and surface water of a water source. Zinc Location concentration in concentration in bottom water Zinc surface water 1 .430 .415 2 .266 .238 3 .567 .390 .531 .410 .707 .605 .716 .609 7 .651 .632 8 .589 .523 9 .469 .411 10 .723 .612 Do the data support that the zinc concentration is less on the surface than the bottom of the water source, at the a =.1 level of significance? a) Express the null and alternative hypotheses in symbolic form for this claim. Assume d = bottom - surface. Enter != for + . Ho: Pd Ha: Pd b) What is the significance level? c) What is the test statistic? Round to 3 decimal places. d) What is the p-value? Round to 4 decimal places. p =

An experiment was conducted to compare the alcohol content of soy sauce on two different production lines. Production was monitored eight times a day. The data are shown here. Production line 1 0.38 0.37 0.39 0.41 0.38 0.39 0.40 0.39 Production line 2 0.48 0.39 0.42 0.52 0.40 0.48 0.52 0.52   Assume both populations are normal. It is suspected that production line 1 is not producing as consistently as production line 2 in terms of alcohol content. Using the 0.05 level of significance, can conclude that the population standard deviations for the alcohol content of these two types of production lines could be the same.

An experiment was conducted to compare the alcohol content of soy sauce on two different production lines. Production was monitored eight times a day. The data are shown here. Production line 1 0.38 0.37 0.39 0.41 0.38 0.39 0.40 0.39 Production line 2 0.48 0.39 0.42 0.52 0.40 0.48 0.52 0.52   Assume both populations are normal. It is suspected that production line 1 is not producing as consistently as production line 2 in terms of alcohol content. Perform a hypothesis test to compare the population standard deviation of these two types of production lines. What is the value of the test statistic?

Below is a table of most of the variables in the dataset. For each variable listed, identify both the type of variable and the level of measurement (e.g., a student’s gender is categorical, nominal). variables type level of measurment exp     wks     bluecol     ind     south     smsa     married     sex     union     ed     black     wage     wage2       1. exp (years of full-time experience)2. wks (weeks worked)3. bluecol (whether the worker is a blue collar worker)4. ind (whether the worker works in a manufacturing industry)5. south (whether the worker resides in the south)6. smsa (whether the worker resides in a standard metropolitan statistical area)7. married (whether the worker is married)8. sex (male or female)9. union (whether the worker is part of a union)10. ed (years of education)11. black (whether the worker is black)12. lwage (gives the logarithm of the worker’s wage)13. wage (gives the worker’s wage this past year)14. wage2 (gives the…

A test was conducted of two overnight mail delivery services. Two samples of identical deliveries were set up so that both delivery services were notified of the need for a delivery at the same time. The hours required to make each delivery follow. Do the data shown suggest a difference in the delivery times for the two services? Use a .05 le of significance for the test. Use Table 1 of Appendix B. Click on the datafile logo to reference the data. DATA file Service Delivery 1 2 24.5 26.0 28.0 21.0 18.0 36.0 25.0 21.0 24.0 26.0 31.0 28.0 25.5 32.0 20.0 19.5 28.0 29.0 22.0 23.5 29.5 30.0 3 4 6. 9. 10 11 What is the z-statistic? If required, round your answer to two decimal places. Enter negative values as negative number, if necessary. .30 What is the p-value? If required, round your answer to two decimal places. .7642 Conclude:

Use the Stata output below to answer the following question. The data used in this analysis is from a sample of airlines. The variables used are: fare-avg price of a one-way fare, in dollars dist- distance of the flight, in miles .reg fare ldist. Source Model Residual 551.391705 Total lfare SS ldist _cons 875.094374 df The OLS results suggest that 1 323.702668 120024315 4,594 MS Coef. Std. Err. 4,595 190444913 Number of obs F(1, 4594) Prob > F R-squared Adj R-squared Root MSE t P>|t| .4025646 .0077517 51.93 0.000 2.399834 .0521601 46.01 0.000 4,596 2696.98 0.0000 0.3699 0.3698 .34645 [95% Conf. Intervall .3873676 .4177617 2.297575 2.502093 a 1% increase in distance is associated with approximately a $.40 increase in the price of the fare. a 1% increase in distance is associated with approximately a .40% increase in the price of the fare. a 1% increase in distance is associated with approximately a 40 % increase in the price of the fare. None of the above.

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Statistics students in Oxnard College sampled 11 textbooks in the Condor bookstore and recorded the number of pages in each textbook and its cost. The bivariate data are shown below: Number of Pages (xx) Cost(yy) 733 51.31 496 30.72 923 63.61 783 64.81 719 57.33 763 52.41 898 62.86 914 73.98 990 76.3 811 56.77 877 57.39 A student calculates a linear modely=_________x  +__________. ( Please show your answers to two decimal places)   Use the model to estimate the cost when number of pages is 735.Cost = $_______________. (Please show your answer to 2 decimal places.)

A paper described a study that examined whether stress accelerates aging at a cellular level. The accompanying data on a measure of perceived stress (x) and telomere length (y) were read from a scatterplot that appeared in the paper. Telomere length is a measure of cell longevity. Perceivedstress Telomerelength Perceivedstress Telomerelength 5 0.93 20 1.19 6 0.94 20 0.95 6 0.96 20 0.91 7 0.92 21 0.95 10 1.14 21 1.2 11 1.03 21 1.08 12 0.92 22 1.11 13 1.06 22 1.23 14 0.99 22 0.89 14 0.9 23 1.27 15 1.16 24 0.94 15 1.07 24 1.08 15 1.09 25 1.2 17 0.95 26 0.98 17 0.93 27 1.16 17 1.11 27 1.25 18 1.01 28 1 18 1.07 29 1.22 19 1.15 33 0.9   (a) Compute the equation of the least-squares line. (Round your answer to four decimal places.)y =        (b) What is the value of r2? (Round your answer to four decimal places.)r2 =