7. The following describe the situation where there is a marginal relationship between X and Y but not a conditional relationship after controlling for a third variable (Z). (List all that apply.) a. A spurious relationship b. A chain relationship c. A suppressor variable d. Modifying relationship e. Simpson's Paradox 43 5 -1.

9. Identify the dependent variable in the statement below " the cost of a smartphone depends on its brand and model"

Exercise 2. Marginal and Conditional Relationships can be Very Different. For 100 mild cases of eczema, a new treatment had a higher cure rate than the old treatment (33.3% of 90 vs. 20% of 10). For 100 severe cases of eczema, again the new treatment had a higher cure rate than the old treatment (60% of 20 vs. 50% of 80). Over all 200 eczema cases, however, the old treatment had a higher cure rate than the new treatment- i.e. Simpson's Paradox strikes again. (a) Compute the overall cure rates for the new and old treatments. (b) Which treatment, old or new, would you choose and why?

1. An online seller would like to know whether the indication of price on Facebook posts will attract consumers more. He posted 50 products for sale on Facebook market, 25 of which he indicated the price while the remaining 25 products, did not have prices. Buyers were just instructed to send him a personal message (pm) if they want to know the price. He then identified which products have greater sales. What is the independent, dependent, and extraneous variable? 2. A housewife wanted to know which soil is best for her pechay plants: the soil purchased from an online seller, soil from her backyard compost or the soil underneath the nearby bamboo tree. She planted 30 pechay seeds into each soil source and then compared the growth of pechay after a month.  What is the independent, dependent, and extraneous variable? 3. Jenny is only borrowing the cellphone chargers of her brother, sister and mother because she lost her phone charger. All chargers are of the same specifications as hers…

The tabie to the right clasifes a stoc's price change as up, down, or no change for both today's and yesterdays prices. Price changes were esamined for 101 days. A fnancial theory states that the price change of today for a stock must be independent of yesterday's prioe change Teet the hypothesis that daily stock price changes for this stock are independent. Let a0.025. Price Change Previous Day Up No Chanue Down 18 Price Change Today Up No Change 9 11 Down 14 13 12 Delermine the nul and atemative hypotheses for the test. Choose the comect answer below DA H Todays prce change and yesterday's price change have equal proportions HA Today's price change and yesterday's price change have non equal proportions ORH Today's price change and yesterday's price change have non-equal proportons. H Today's price change and yesterday's price change have equal proportions E H Today' price change and yesterday's price change are independent HA Today's price change and yesterday's price change are not…

Which of these statements is not a condition for an exposure to quality as a risk factor?   There is a dose-response relationship   There is temporality of the exposure and the disease in terms of occurrence   The observed relationship between exposure and the disease in not due to some source of error in the design   The observed relationship between exposure and the disease is due to due to some source of error in the design.

Which of the following are reasons that are potential limitations to a research study? Choose all that apply.  People who were refused to answer  The graphs are drawn in a way to mislead the reader  The research was not able to survey every individual from the population   The funders of the project are partial to the results  Trying to conclude that there is a cause – and- effect relationship when something else causes both   Two factors cannot be separated to determine which is the one that is responsible to outcome

The table to the right classifies a stock's price change as up, down, or no change for both today's and yesterday's prices Price changes were examined for 104 days. A financial theory states that the price change of today for a stock must be independent of yesterday's price change. Test the hypothesis that daily stock price changes for this stock are independent. Let a=0.10. Price Change Previous Day Up No Change Down 16 Price Change Today 13 Up No Change 7 Down 14 16 10 13 Determine the null and alternative hypotheses for the test. Choose the correct answer below. O A. Ho: Today's price change and yesterday's price change are not independent. HA: Today's price change and yesterday's price change are independent. O B. Ho: Today's price change and yesterday's price change are independent. HA: Today's price change and yesterday's price change are not independent. OC. Ho: Today's price change and yesterday's price change have non-equal proportions. HA: Today's price change and yesterday's…

2. In a simple regression analysis where Yisa dependent and an independent variable)if the Y intercept is positive then A. there is a positive relation between X and Y B. if Y is increased must also increase C. None D. if x increased y must also increase

A researcher would like to know if the gestation period of an animal can be used to predict the life expectancy. She collects the following data. Animal Gestation (incubation) Period (days) Life Expectancy (years) Cat 63 11 Chicken 22 7.5 Dog 63 11 Duck 28 10 Goat 151 12 Lion 108 10