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Estriol Level and Birth Weight. J. Greene and J. Touchstone conducted a study on the relationship between the estriol levels of pregnant women and the birth weights of their children. Their findings. "Urinary Tract Estriol: An Index of Placental Function," were published in the American lournal of obstetrics and Gynecology (Vol. 85(1). pp. 1-9). The data from the study are provided on the WeissStats site, where estriol levels are in $mg/24hr$birth weights are in hectograms.

We have to decide whether finding a regression line for the data is reasonable. If so, then also do parts (b) (d).

The MINITAB: can be used to create a scatterplot for the given data.

Step 1: to Graph > Scatterplot.

Step 2: Click OK after selecting With Connect Line.

Step 3: Add a WEIGHT column to the $Y$variables section.

Step 4: Add an ESTRIOL column to the $X$variables.

Step 5: Click the OK button.

The resulting scatterplot will be

Because the observations are dispersed around a line in the scatterplot above, it is reasonable to find a regression line for the data.

Estriol Level and Birth Weight. J. Greene and J. Touchstone conducted a study on the relationship between the estriol levels of pregnant women and the birth weights of their children. Their findings. "Urinary Tract Estriol: An Index of Placental Function," were published in the American lournal of obstetrics and Gynecology (Vol. 85(1). pp. 1-9). The data from the study are provided on the WeissStats site, where estriol levels are in $mg/24hr$ birth weights are in hectograms. we have to determine the coefficient of determination.

MINITAB can be used to calculate the coefficient of determination as follows:

Step 1: go to Stat > Regression > Regression.

Step 2: In the Response column, type WEIGHT.

Step 3: In Predictors, add the ESTRIOL column.

Step 4: Click the OK button.

MINITAB's output will be as follows:

Therefore the coefficient of determination is$0.3718$

Estriol Level and Birth Weight. J. Greene and J. Touchstone conducted a study on the relationship between the estriol levels of pregnant women and the birth weights of their children. Their findings. "Urinary Tract Estriol: An Index of Placental Function," were published in the American lournal of obstetrics and Gynecology (Vol. 85(1). pp. 1-9). The data from the study are provided on the WeissStats site, where estriol levels are in $mg/24hr$birth weights are in hectograms. we have to determine the percentage of variation in the observed values of the response variable explained by the regression .

The coefficient of determination will be $0.3718$

As a result, the regression explains $37.18\%$t of the variation in the observed values of the response variable. It can be deduced that the linear association between Estriol level $\left(x\right)$and birth weight accounts for $37.18\%$of the variability in birth weight $\left(y\right)$.

Estriol Level and Birth Weight. J. Greene and J. Touchstone conducted a study on the relationship between the estriol levels of pregnant women and the birth weights of their children. Their findings. "Urinary Tract Estriol: An Index of Placental Function," were published in the American lournal of obstetrics and Gynecology (Vol. 85(1). pp. 1-9). The data from the study are provided on the WeissStats site, where estriol levels are in $mg/24hr$ birth weights are in hectograms. we have to state how useful the regression equation appears to be for making predictions.

The coefficient of determination will be $0.3718$

As a result, the regression explains $37.18\%$of the variation in the observed values of the response variable. It can be deduced that the linear association between Estriol level $\left(x\right)$and birth weight accounts for$37.18\%$of the variability in birth weight $\left(y\right)$

Because the proportion of variance in the observed values of the response variable explained by the regression is less than $50$percent, the regression equation is not useful in making predictions.