econ work
3rd Statistical computing assignment
1) The following model can be used to study whether campaign expenditures affect election outcomes:
Where is the percentage of the votes received by candidate A, and are campaign expenditures by Candidates A and B, and is a measure of party strength for Candidate A.
a. What is the interpretation of ?
b. In terms of the parameters, state the null hypothesis that a 1% increase in As expenditures is offset by a 1% increase in Bs expenditures.
c. Estimate the given model using the data in VOTE1 and report the results in the usual form. Do As expenditures affect the outcome? What about Bs expenditures? Can you use these results to test the hypothesis in part (b)?
d. Estimate a model that directly gives the t-statistic for testing the hypothesis in part (b). What do you conclude? (use a two-sided alternative).
2) Use the data in WAGE2 for this exercise.
a. Consider the standard wage equation
State the null hypothesis that another year of general workforce experience has the same effect on as another year of tenure with the current employer.
b. Test the null hypothesis in part (a) against a two-sided alternative, at the 5% significance level, by constructing a 95% confidence interval. What do you conclude?
3) Use the data in ELEM94_95 to answer the following parts. The findings can be compared with those in table 4.1 in your text. The dependent variable is the log of average teacher salary and is the ratio of average benefits to average salary (by school).
a. Run the simple regression of on . Is the estimated slope statistically different from zero? Is it statistically different from -1?
b. Add the variables and to the regression from part (a). What happens to the coefficient on ? How does the situation compare with that in Table 4.1?
c. How come the standard error on the coefficient is smaller in part (b) than in part (a)?
d. How come the coefficient on is negative? Is it large in magnitude?
e. Now add the variable to the regression. Holding other factors fixed, are teachers being compensated for teaching students from disadvantaged backgrounds? Explain.
f. Overall, is the pattern of results that you find with ELEM94_95 consistent with the pattern in Table 4.1?
4) Use the data in ECONMATH to answer the following questions.
a. Estimate a model explaining to and . Report the results in the usual form. Are all explanatory variables statistically significant?
b. Consider an increase in of one standard deviation, about .343. By how much does increase, holding and fixed. About how many standard deviations would the have to increase to change by the same amount as a one standard deviation in ? Comment.
c. Test the null hypothesis that and have the same effect in the population against a two-sided alternative. Report the p-value and describe your conclusions.
d. Suppose the college admissions officer wants you to use the data on the variables in part (a) to create an equation that explains at least 50% of the variation in . What would you tell the officer?
5) Use the data KIELMC, only for year 1981, to answer the following parts. The data are for houses that sold during 1981 in North Andover, MA; 1981 was the year construction began on a local garbage incinerator.
a. To study the effects of the incinerator location on housing price, consider the simple regression model
Where is housing price in dollars and is distance from the house to the incinerator measured in feet. Interpreting this equation causally, what sign do you expect for if the presence of the incinerator depresses housing prices? Estimate this equation and interpret the results.
b. To the simple regression in part (a), please add the variables and , where is distance from the home to the interstate, is square footage of the house, is the lot size in square feet, is total number of rooms, is number of bathrooms, and is the age of the house in years. Now, what do you conclude about the effects of the incinerator? Explain why (a) and (b) give conflicting results.
c. Add to the model in part (b). Now what happens? What do you conclude about the importance of functional form?
d. Is the square of significant when you add it to the model from part (c)?
6) Use the data in WAGE1 for this exercise.
a. Use OLS to estimate the equation
And report the results using the usual format (equation, n, ).
b. Is statistically significant at the 99% confidence level?
c. Using the approximation
Find the approximate return to the fifth year of experience. What is the approximate return to the 20th year of experience?
d. At what value of does additional experience actually lower predicted ? How many people have more experience than this in the sample?
7) Use the data in VOTE1 for this exercise.
a. Consider a model with an interaction term between expenditures:
What is the partial effect of on , holding and fixed? What is the partial effect of on ? Is the expected sign for obvious?
b. Estimate the equation in part (a) and report the results in the usual form. Is the interaction term statistically significant?
c. Find the average of in the sample. Fix at 300 (for $300,000). What is the estimated effect of another $100,000 spent by Candidate B on ? Is this a large effect?
d. Now fix at 100. What is the estimated effect of on ? Does this make sense?
e. Now, estimate a model that replaces the interaction with , Candidate As percentage share of total campaign expenditures. Does it make sense to hold both and fixed, while changing ?
f. In the model from part (e), find the partial effect of on , holding and fixed. Evaluate this at and and comment on the results. Data Sets- STATA/401K.DTA
Data Sets- STATA/401ksubs.dta
Data Sets- STATA/ADMNREV.DTA
Data Sets- STATA/affairs.dta
Data Sets- STATA/airfare.dta
Data Sets- STATA/alcohol.dta
Data Sets- STATA/APPLE.DTA
Data Sets- STATA/approval.dta
Data Sets- STATA/ATHLET1.DTA
Data Sets- STATA/ATHLET2.DTA
Data Sets- STATA/attend.dta
Data Sets- STATA/AUDIT.DTA
Data Sets- STATA/BARIUM.DTA
Data Sets- STATA/beauty.dta
Data Sets- STATA/benefits.dta
Data Sets- STATA/beveridge.dta
Data Sets- STATA/big9salary.dta
Data Sets- STATA/BWGHT.DTA
Data Sets- STATA/bwght2.dta
Data Sets- STATA/campus.dta
Data Sets- STATA/CARD.DTA
Data Sets- STATA/catholic.dta
Data Sets- STATA/cement.dta
Data Sets- STATA/census2000.dta
Data Sets- STATA/CEOSAL1.DTA
Data Sets- STATA/CEOSAL2.DTA
Data Sets- STATA/charity.dta
Data Sets- STATA/consump.dta
Data Sets- STATA/CORN.DTA
Data Sets- STATA/countymurders.dta
Data Sets- STATA/CPS78_85.DTA
Data Sets- STATA/cps91.dta
Data Sets- STATA/CRIME1.DTA
Data Sets- STATA/CRIME2.DTA
Data Sets- STATA/CRIME3.DTA
Data Sets- STATA/CRIME4.DTA
Data Sets- STATA/discrim.dta
Data Sets- STATA/driving.dta
Data Sets- STATA/EARNS.DTA
Data Sets- STATA/econmath.dta
Data Sets- STATA/elem94_95.dta
Data Sets- STATA/engin.dta
Data Sets- STATA/expendshares.dta
Data Sets- STATA/EZANDERS.DTA
Data Sets- STATA/ezunem.dta
Data Sets- STATA/FAIR.DTA
Data Sets- STATA/FERTIL1.DTA
Data Sets- STATA/FERTIL2.DTA
Data Sets- STATA/FERTIL3.DTA
Data Sets- STATA/FISH.DTA
Data Sets- STATA/FRINGE.DTA
Data Sets- STATA/GPA1.DTA
Data Sets- STATA/gpa2.dta
Data Sets- STATA/GPA3.DTA
Data Sets- STATA/happiness.dta
Data Sets- STATA/hprice1.dta
Data Sets- STATA/HPRICE2.DTA
Data Sets- STATA/HPRICE3.DTA
Data Sets- STATA/HSEINV.DTA
Data Sets- STATA/HTV.DTA
Data Sets- STATA/infmrt.dta
Data Sets- STATA/INJURY.DTA
Data Sets- STATA/intdef.dta
Data Sets- STATA/INTQRT.DTA
Data Sets- STATA/INVEN.DTA
Data Sets- STATA/JTRAIN.DTA
Data Sets- STATA/JTRAIN2.DTA
Data Sets- STATA/jtrain3.dta
Data Sets- STATA/jtrain98.dta
Data Sets- STATA/KIELMC.DTA
Data Sets- STATA/labsup.dta
Data Sets- STATA/LAWSCH85.DTA
Data Sets- STATA/loanapp.dta
Data Sets- STATA/LOWBRTH.DTA
Data Sets- STATA/mathpnl.dta
Data Sets- STATA/meap00_01.dta
Data Sets- STATA/meap01.dta
Data Sets- STATA/MEAP93.DTA
Data Sets- STATA/meapsingle.dta
Data Sets- STATA/minwage.dta
Data Sets- STATA/MLB1.DTA
Data Sets- STATA/MROZ.DTA
Data Sets- STATA/MURDER.DTA
Data Sets- STATA/nbasal.dta
Data Sets- STATA/ncaa_rpi.dta
Data Sets- STATA/NYSE.DTA
Data Sets- STATA/okun.dta
Data Sets- STATA/OPENNESS.DTA
Data Sets- STATA/PENSION.DTA
Data Sets- STATA/phillips.dta
Data Sets- STATA/PNTSPRD.DTA
Data Sets- STATA/PRISON.DTA
Data Sets- STATA/PRMINWGE.DTA
Data Sets- STATA/RDCHEM.DTA
Data Sets- STATA/rdtelec.dta
Data Sets- STATA/recid.dta
Data Sets- STATA/RENTAL.DTA
Data Sets- STATA/RETURN.DTA
Data Sets- STATA/SAVING.DTA
Data Sets- STATA/school93_98.dta
Data Sets- STATA/SLEEP75.DTA
Data Sets- STATA/SLP75_81.DTA
Data Sets- STATA/SMOKE.DTA
Data Sets- STATA/TRAFFIC1.DTA
Data Sets- STATA/TRAFFIC2.DTA
Data Sets- STATA/twoyear.dta
Data Sets- STATA/VOLAT.DTA
Data Sets- STATA/VOTE1.DTA
Data Sets- STATA/VOTE2.DTA
Data Sets- STATA/voucher.dta
Data Sets- STATA/WAGE1.DTA
Data Sets- STATA/WAGE2.DTA
Data Sets- STATA/wagepan.dta
Data Sets- STATA/WAGEPRC.DTA
Data Sets- STATA/wine.dta
