stats homework 15 questions needed in 6 hours
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Below is the simple crosstab for Beta Blocker use vs. Low HDL. The natural log of the odds ratio [ln(OR)]=
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Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Using the table from question 1, the standard error of ln(OR)= |
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Using the answer for the two previous questions, calculate a 95% CI for OR (Note, you will have to convert your answer from log form before you select an answer).
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In this assignment, you will use the data set “ birthwt3.sav ”, in homework files under resources. This time we will use the clinical criterion for low birth weight (<2500 grams) to determine whether the baby is of low birth weight. Then you will use logistic regression to examine the effects of risk factors on the chance of a mother having a low birth weight baby. The dataset contains the following variables: ID: Mother’s identification number MOTH_AGE: Mother’s age (years) MOTH_WT: Mother’s weight (pounds) RACE: Mother’s race (1=White, 2=Black, 3=Other) dummy variables (Black, White and Other) are already coded in the data set. SMOKE: Mother’s smoking status (1=Yes, 0=No) PERM: History of premature labor (number of times) HYPE: History of hypertension (1=Yes, 0=N0) URIN_IRR: History of urinary irritation (1=Yes, 0=N0) PHYS_VIS: Number of physician visits BIRTH_WT Birth weight of new born (grams) LBW: Dummy variable, coded 1 if the baby has low birth weight Run a logistic regression to predict the outcome “LBW” using Smoke, Black and Other as the independent variables. Based on the logistic regression results, match the odds ratio for each of the variables.
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We cannot make which of the following conclusions based on the results above?
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Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. The odds of having low birth weight baby for a Black women who smoked during pregnancy is |
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Run a second logistic regression to further include “age” and “weight” as independent variables. Based on the logistic regression results, which one of the following statements is incorrect?
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Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Based on the model above, what is the odds of having low birth weight baby for a 25 year-old Black woman who weighs 120 pounds and who did not smoke during pregnancy? |
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Run a third logistic regression to further include variables about medical history including: history of premature labor, hypertension, urinary irritation and number of physician visits. Check “Hosmer and Lemeshow goodness-of fit” statistics in “Options." Check "Probabilities" and "group membership" in "Save." Which one of the following variables regarding medical history has significant impact (at level 5%) on the risk of women having low birth weight babies?
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Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. Based on the third model, overall what percentage of the sample is correctly predicted? (Please do not include "%" in your answer. If it is 50.0%, write 50.0) |
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Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. For the participant on line 73 (ID number 164.00), what is the predicted probability of LBW using model 3. (Hint, to find the answer you will have to go to data view and pull it out of the dataset under the PRE_ column). Report the number exactly as it appears in the data |
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Is the participant on line 94 of the dataset (ID number 188.00) correctly classified by the model. (Once again you will have to look at the data view and the PGR_ column)
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Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker. Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values. For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not. What is the Cox Snell Pseudo R square for model 3? |
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What is the null hypothesis for the Hosmer–Lemeshow test?
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Based on the Hosmer–Lemeshow test, the thrid logisitic regression fits data well.
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