{smcl}
{com}{sf}{ul off}{txt}{.-}
      name:  {res}<unnamed>
       {txt}log:  {res}/Users/steve/Documents/teaching/c2015/biostat208/labs/lab3/lab3.smcl
  {txt}log type:  {res}smcl
 {txt}opened on:  {res}21 Jan 2015, 17:50:43
{txt}
{com}. use lab3, clear
{txt}
{com}. 
. tab physact, sum(bmi)

{txt}comparative {c |}
   physical {c |}       Summary of BMI (kg/m^2)
   activity {c |}        Mean   Std. Dev.       Freq.
{hline 12}{c +}{hline 36}
  much less {c |}  {res} 30.867194   7.0607121         196
  {txt}somewhat  {c |}  {res} 30.343944   6.0039264         502
  {txt}about as  {c |}  {res} 29.031647   5.5072779         917
  {txt}somewhat  {c |}  {res} 27.249821   4.4781094         837
  {txt}much more {c |}  {res} 26.499412   4.4468966         306
{txt}{hline 12}{c +}{hline 36}
      Total {c |}  {res} 28.579249   5.5177834        2758
{txt}
{com}. reg bmi i.physact

      {txt}Source {c |}       SS       df       MS              Number of obs ={res}    2758
{txt}{hline 13}{char +}{hline 30}           F(  4,  2753) ={res}   49.01
    {txt}   Model {char |} {res} 5579.94674     4  1394.98669           {txt}Prob > F      = {res} 0.0000
    {txt}Residual {char |} {res} 78359.4937  2753  28.4633105           {txt}R-squared     = {res} 0.0665
{txt}{hline 13}{char +}{hline 30}           Adj R-squared = {res} 0.0651
    {txt}   Total {char |} {res} 83939.4405  2757  30.4459342           {txt}Root MSE      = {res} 5.3351

{txt}{hline 22}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}                  bmi{col 23}{c |}      Coef.{col 35}   Std. Err.{col 47}      t{col 55}   P>|t|{col 63}     [95% Con{col 76}f. Interval]
{hline 22}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 14}physact {c |}
somewhat less active  {c |}{col 23}{res}{space 2}-.5232496{col 35}{space 2}  .449356{col 46}{space 1}   -1.16{col 55}{space 3}0.244{col 63}{space 4}-1.404359{col 76}{space 3} .3578593
{txt}{space 5}about as active  {c |}{col 23}{res}{space 2}-1.835547{col 35}{space 2}  .419834{col 46}{space 1}   -4.37{col 55}{space 3}0.000{col 63}{space 4}-2.658769{col 76}{space 3}-1.012326
{txt}somewhat more active  {c |}{col 23}{res}{space 2}-3.617373{col 35}{space 2} .4233525{col 46}{space 1}   -8.54{col 55}{space 3}0.000{col 63}{space 4}-4.447494{col 76}{space 3}-2.787253
{txt}{space 4}much more active  {c |}{col 23}{res}{space 2}-4.367782{col 35}{space 2} .4880966{col 46}{space 1}   -8.95{col 55}{space 3}0.000{col 63}{space 4}-5.324855{col 76}{space 3}-3.410709
{txt}{space 21} {c |}
{space 16}_cons {c |}{col 23}{res}{space 2} 30.86719{col 35}{space 2} .3810787{col 46}{space 1}   81.00{col 55}{space 3}0.000{col 63}{space 4} 30.11996{col 76}{space 3} 31.61442
{txt}{hline 22}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}{txt}
{com}. * again, showing reference level
. reg bmi i.physact, baselevels

      {txt}Source {c |}       SS       df       MS              Number of obs ={res}    2758
{txt}{hline 13}{char +}{hline 30}           F(  4,  2753) ={res}   49.01
    {txt}   Model {char |} {res} 5579.94674     4  1394.98669           {txt}Prob > F      = {res} 0.0000
    {txt}Residual {char |} {res} 78359.4937  2753  28.4633105           {txt}R-squared     = {res} 0.0665
{txt}{hline 13}{char +}{hline 30}           Adj R-squared = {res} 0.0651
    {txt}   Total {char |} {res} 83939.4405  2757  30.4459342           {txt}Root MSE      = {res} 5.3351

{txt}{hline 22}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}                  bmi{col 23}{c |}      Coef.{col 35}   Std. Err.{col 47}      t{col 55}   P>|t|{col 63}     [95% Con{col 76}f. Interval]
{hline 22}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 14}physact {c |}
{space 4}much less active  {c |}{col 23}{res}{space 2}        0{col 35}{txt}  (base)
somewhat less active  {c |}{col 23}{res}{space 2}-.5232496{col 35}{space 2}  .449356{col 46}{space 1}   -1.16{col 55}{space 3}0.244{col 63}{space 4}-1.404359{col 76}{space 3} .3578593
{txt}{space 5}about as active  {c |}{col 23}{res}{space 2}-1.835547{col 35}{space 2}  .419834{col 46}{space 1}   -4.37{col 55}{space 3}0.000{col 63}{space 4}-2.658769{col 76}{space 3}-1.012326
{txt}somewhat more active  {c |}{col 23}{res}{space 2}-3.617373{col 35}{space 2} .4233525{col 46}{space 1}   -8.54{col 55}{space 3}0.000{col 63}{space 4}-4.447494{col 76}{space 3}-2.787253
{txt}{space 4}much more active  {c |}{col 23}{res}{space 2}-4.367782{col 35}{space 2} .4880966{col 46}{space 1}   -8.95{col 55}{space 3}0.000{col 63}{space 4}-5.324855{col 76}{space 3}-3.410709
{txt}{space 21} {c |}
{space 16}_cons {c |}{col 23}{res}{space 2} 30.86719{col 35}{space 2} .3810787{col 46}{space 1}   81.00{col 55}{space 3}0.000{col 63}{space 4} 30.11996{col 76}{space 3} 31.61442
{txt}{hline 22}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}{txt}
{com}. * compute mean BMI at each level of physact
. forvalues i = 1/5 {c -(}
{txt}  2{com}. lincom _cons + `i'.physact
{txt}  3{com}. {c )-}

{p 0 7}{space 1}{text:( 1)}{space 1} {res}1b.physact + _cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}         bmi{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      t{col 46}   P>|t|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 30.86719{col 26}{space 2} .3810787{col 37}{space 1}   81.00{col 46}{space 3}0.000{col 54}{space 4} 30.11996{col 67}{space 3} 31.61442
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{p 0 7}{space 1}{text:( 1)}{space 1} {res}2.physact + _cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}         bmi{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      t{col 46}   P>|t|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 30.34394{col 26}{space 2} .2381172{col 37}{space 1}  127.43{col 46}{space 3}0.000{col 54}{space 4} 29.87704{col 67}{space 3} 30.81085
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{p 0 7}{space 1}{text:( 1)}{space 1} {res}3.physact + _cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}         bmi{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      t{col 46}   P>|t|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 29.03165{col 26}{space 2} .1761806{col 37}{space 1}  164.78{col 46}{space 3}0.000{col 54}{space 4} 28.68619{col 67}{space 3} 29.37711
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{p 0 7}{space 1}{text:( 1)}{space 1} {res}4.physact + _cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}         bmi{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      t{col 46}   P>|t|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 27.24982{col 26}{space 2} .1844081{col 37}{space 1}  147.77{col 46}{space 3}0.000{col 54}{space 4} 26.88823{col 67}{space 3} 27.61141
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{p 0 7}{space 1}{text:( 1)}{space 1} {res}5.physact + _cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}         bmi{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      t{col 46}   P>|t|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 26.49941{col 26}{space 2} .3049875{col 37}{space 1}   86.89{col 46}{space 3}0.000{col 54}{space 4} 25.90138{col 67}{space 3} 27.09744
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. * again, using margins
. margins physact
{res}
{txt}Adjusted predictions{col 51}Number of obs{col 67}= {res}      2758
{txt}Model VCE{col 14}: {res}OLS

{txt}{p2colset 1 14 16 2}{...}
{p2col:Expression}:{space 1}{res:Linear prediction, predict()}{p_end}
{p2colreset}{...}

{res}{txt}{hline 22}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 23}{c |}{col 35} Delta-method
{col 23}{c |}     Margin{col 35}   Std. Err.{col 47}      t{col 55}   P>|t|{col 63}     [95% Con{col 76}f. Interval]
{hline 22}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 14}physact {c |}
{space 4}much less active  {c |}{col 23}{res}{space 2} 30.86719{col 35}{space 2} .3810787{col 46}{space 1}   81.00{col 55}{space 3}0.000{col 63}{space 4} 30.11996{col 76}{space 3} 31.61442
{txt}somewhat less active  {c |}{col 23}{res}{space 2} 30.34394{col 35}{space 2} .2381172{col 46}{space 1}  127.43{col 55}{space 3}0.000{col 63}{space 4} 29.87704{col 76}{space 3} 30.81085
{txt}{space 5}about as active  {c |}{col 23}{res}{space 2} 29.03165{col 35}{space 2} .1761806{col 46}{space 1}  164.78{col 55}{space 3}0.000{col 63}{space 4} 28.68619{col 76}{space 3} 29.37711
{txt}somewhat more active  {c |}{col 23}{res}{space 2} 27.24982{col 35}{space 2} .1844081{col 46}{space 1}  147.77{col 55}{space 3}0.000{col 63}{space 4} 26.88823{col 76}{space 3} 27.61141
{txt}{space 4}much more active  {c |}{col 23}{res}{space 2} 26.49941{col 35}{space 2} .3049875{col 46}{space 1}   86.89{col 55}{space 3}0.000{col 63}{space 4} 25.90138{col 76}{space 3} 27.09744
{txt}{hline 22}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}{txt}
{com}. 
. * test for heterogeneity
. testparm i.physact

{p 0 7}{space 1}{text:( 1)}{space 1} {res}2.physact = 0{p_end}
{p 0 7}{space 1}{text:( 2)}{space 1} 3.physact = 0{p_end}
{p 0 7}{space 1}{text:( 3)}{space 1} 4.physact = 0{p_end}
{p 0 7}{space 1}{text:( 4)}{space 1} 5.physact = 0{p_end}

{txt}       F(  4,  2753) ={res}   49.01
{txt}{col 13}Prob > F ={res}    0.0000
{txt}
{com}. * test for linear trend
. contrast q(1).physact, noeffects
{res}
{txt}Contrasts of marginal linear predictions

{txt}{p2colset 1 14 16 2}{...}
{p2col:Margins}:{space 1}{res:asbalanced}{p_end}
{p2colreset}{...}

{col 1}{text}{hline 13}{c TT}{hline 11}{hline 12}{hline 11}
{col 14}{text}{c |}         df{col 26}           F{col 38}        P>F
{col 1}{text}{hline 13}{c +}{hline 11}{hline 12}{hline 11}
{space 5}physact {col 14}{text}{c |}{result}{space 2}        1{col 26}{space 3}   134.09{col 38}{space 2}   0.0000
{col 14}{text}{c |}
{col 1}{text} Denominator{col 14}{c |}{result}{space 2}     2753
{col 1}{text}{hline 13}{c BT}{hline 11}{hline 12}{hline 11}

{com}. * test for departure from linear trend
. contrast q(2/4).physact, noeffects
{res}
{txt}Contrasts of marginal linear predictions

{txt}{p2colset 1 14 16 2}{...}
{p2col:Margins}:{space 1}{res:asbalanced}{p_end}
{p2colreset}{...}

{col 1}{text}{hline 13}{c TT}{hline 11}{hline 12}{hline 11}
{col 14}{text}{c |}         df{col 26}           F{col 38}        P>F
{col 1}{text}{hline 13}{c +}{hline 11}{hline 12}{hline 11}
{space 5}physact {c |}
(quadratic)  {col 14}{text}{c |}{result}{space 2}        1{col 26}{space 3}     0.73{col 38}{space 2}   0.3927
{txt}    (cubic)  {col 14}{text}{c |}{result}{space 2}        1{col 26}{space 3}     5.51{col 38}{space 2}   0.0189
{txt}  (quartic)  {col 14}{text}{c |}{result}{space 2}        1{col 26}{space 3}     0.50{col 38}{space 2}   0.4808
{col 1}{text}      Joint {col 14}{c |}{result}{space 2}        3{col 26}{space 3}     2.45{col 38}{space 2}   0.0615
{col 14}{text}{c |}
{col 1}{text} Denominator{col 14}{c |}{result}{space 2}     2753
{col 1}{text}{hline 13}{c BT}{hline 11}{hline 12}{hline 11}

{com}. 
. * repeat with adjustment for age, smoking, and alcohol use
. reg bmi i.physact age10 smoking drnkspwk

      {txt}Source {c |}       SS       df       MS              Number of obs ={res}    2758
{txt}{hline 13}{char +}{hline 30}           F(  7,  2750) ={res}   51.75
    {txt}   Model {char |} {res} 9770.72238     7  1395.81748           {txt}Prob > F      = {res} 0.0000
    {txt}Residual {char |} {res} 74168.7181  2750  26.9704429           {txt}R-squared     = {res} 0.1164
{txt}{hline 13}{char +}{hline 30}           Adj R-squared = {res} 0.1142
    {txt}   Total {char |} {res} 83939.4405  2757  30.4459342           {txt}Root MSE      = {res} 5.1933

{txt}{hline 22}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}                  bmi{col 23}{c |}      Coef.{col 35}   Std. Err.{col 47}      t{col 55}   P>|t|{col 63}     [95% Con{col 76}f. Interval]
{hline 22}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 14}physact {c |}
somewhat less active  {c |}{col 23}{res}{space 2}-.6280119{col 35}{space 2} .4376396{col 46}{space 1}   -1.43{col 55}{space 3}0.151{col 63}{space 4}-1.486147{col 76}{space 3} .2301235
{txt}{space 5}about as active  {c |}{col 23}{res}{space 2}-1.802389{col 35}{space 2} .4101722{col 46}{space 1}   -4.39{col 55}{space 3}0.000{col 63}{space 4}-2.606665{col 76}{space 3}-.9981121
{txt}somewhat more active  {c |}{col 23}{res}{space 2}-3.490371{col 35}{space 2} .4154996{col 46}{space 1}   -8.40{col 55}{space 3}0.000{col 63}{space 4}-4.305094{col 76}{space 3}-2.675648
{txt}{space 4}much more active  {c |}{col 23}{res}{space 2}-4.104422{col 35}{space 2} .4783847{col 46}{space 1}   -8.58{col 55}{space 3}0.000{col 63}{space 4}-5.042452{col 76}{space 3}-3.166392
{txt}{space 21} {c |}
{space 16}age10 {c |}{col 23}{res}{space 2}-1.290458{col 35}{space 2} .1536594{col 46}{space 1}   -8.40{col 55}{space 3}0.000{col 63}{space 4}-1.591757{col 76}{space 3}-.9891585
{txt}{space 14}smoking {c |}{col 23}{res}{space 2}-2.574357{col 35}{space 2} .3006797{col 46}{space 1}   -8.56{col 55}{space 3}0.000{col 63}{space 4}-3.163938{col 76}{space 3}-1.984776
{txt}{space 13}drnkspwk {c |}{col 23}{res}{space 2}-.1580992{col 35}{space 2} .0271912{col 46}{space 1}   -5.81{col 55}{space 3}0.000{col 63}{space 4}-.2114164{col 76}{space 3}-.1047821
{txt}{space 16}_cons {c |}{col 23}{res}{space 2} 39.95839{col 35}{space 2} 1.077797{col 46}{space 1}   37.07{col 55}{space 3}0.000{col 63}{space 4} 37.84502{col 76}{space 3} 42.07177
{txt}{hline 22}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}{txt}
{com}. * compute marginal mean BMI at each level of physact, 
. * averaging over other predictors
. margins physact
{res}
{txt}Predictive margins{col 51}Number of obs{col 67}= {res}      2758
{txt}Model VCE{col 14}: {res}OLS

{txt}{p2colset 1 14 16 2}{...}
{p2col:Expression}:{space 1}{res:Linear prediction, predict()}{p_end}
{p2colreset}{...}

{res}{txt}{hline 22}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 23}{c |}{col 35} Delta-method
{col 23}{c |}     Margin{col 35}   Std. Err.{col 47}      t{col 55}   P>|t|{col 63}     [95% Con{col 76}f. Interval]
{hline 22}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 14}physact {c |}
{space 4}much less active  {c |}{col 23}{res}{space 2} 30.80748{col 35}{space 2} .3726344{col 46}{space 1}   82.67{col 55}{space 3}0.000{col 63}{space 4}  30.0768{col 76}{space 3} 31.53815
{txt}somewhat less active  {c |}{col 23}{res}{space 2} 30.17946{col 35}{space 2} .2333813{col 46}{space 1}  129.31{col 55}{space 3}0.000{col 63}{space 4} 29.72184{col 76}{space 3} 30.63708
{txt}{space 5}about as active  {c |}{col 23}{res}{space 2} 29.00509{col 35}{space 2} .1715376{col 46}{space 1}  169.09{col 55}{space 3}0.000{col 63}{space 4} 28.66873{col 76}{space 3} 29.34144
{txt}somewhat more active  {c |}{col 23}{res}{space 2}  27.3171{col 35}{space 2}   .18039{col 46}{space 1}  151.43{col 55}{space 3}0.000{col 63}{space 4} 26.96339{col 76}{space 3} 27.67082
{txt}{space 4}much more active  {c |}{col 23}{res}{space 2} 26.70305{col 35}{space 2} .2978692{col 46}{space 1}   89.65{col 55}{space 3}0.000{col 63}{space 4} 26.11898{col 76}{space 3} 27.28712
{txt}{hline 22}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}{txt}
{com}. * verifiy results from last command
. gen y1 = _b[_cons] + _b[1.physact]*1 + _b[age10 ]*age10 + _b[smoking]*smoking + _b[drnkspwk]*drnkspwk if e(sample)
{txt}(5 missing values generated)

{com}. gen y2 = _b[_cons] + _b[2.physact]*1 + _b[age10 ]*age10 + _b[smoking]*smoking + _b[drnkspwk]*drnkspwk if e(sample)
{txt}(5 missing values generated)

{com}. gen y3 = _b[_cons] + _b[3.physact]*1 + _b[age10 ]*age10 + _b[smoking]*smoking + _b[drnkspwk]*drnkspwk if e(sample) 
{txt}(5 missing values generated)

{com}. gen y4 = _b[_cons] + _b[4.physact]*1 + _b[age10 ]*age10 + _b[smoking]*smoking + _b[drnkspwk]*drnkspwk if e(sample) 
{txt}(5 missing values generated)

{com}. gen y5 = _b[_cons] + _b[5.physact]*1 + _b[age10 ]*age10 + _b[smoking]*smoking + _b[drnkspwk]*drnkspwk if e(sample) 
{txt}(5 missing values generated)

{com}. summ y1 y2 y3 y4 y5

{txt}    Variable {c |}       Obs        Mean    Std. Dev.       Min        Max
{hline 13}{c +}{hline 56}
{space 10}y1 {c |}{res}      2758    30.80747    1.237514   22.46061   34.24349
{txt}{space 10}y2 {c |}{res}      2758    30.17946    1.237514   21.83259   33.61548
{txt}{space 10}y3 {c |}{res}      2758    29.00509    1.237514   20.65822    32.4411
{txt}{space 10}y4 {c |}{res}      2758     27.3171    1.237514   18.97024   30.75312
{txt}{space 10}y5 {c |}{res}      2758    26.70305    1.237514   18.35618   30.13907
{txt}
{com}. 
. * compute marginal mean BMI at each level of physact, 
. * with other predictors fixed at mean values
. margins physact, atmeans
{res}
{txt}Adjusted predictions{col 51}Number of obs{col 67}= {res}      2758
{txt}Model VCE{col 14}: {res}OLS

{txt}{p2colset 1 14 16 2}{...}
{p2col:Expression}:{space 1}{res:Linear prediction, predict()}{p_end}
{p2colreset}{...}
{txt}{p2colset 1 14 16 2}{...}
{p2col:at}:{space 1}{res:{txt:1.physact}{space 7}{txt:=} {space 4}.071066 {txt:(mean)}}{p_end}
{p2colreset}{...}
{txt}{p2colset 1 14 16 2}{...}
{p2col: }{space 2}{res:{txt:2.physact}{space 7}{txt:=} {space 4}.182016 {txt:(mean)}}{p_end}
{p2colreset}{...}
{txt}{p2colset 1 14 16 2}{...}
{p2col: }{space 2}{res:{txt:3.physact}{space 7}{txt:=} {space 3}.3324873 {txt:(mean)}}{p_end}
{p2colreset}{...}
{txt}{p2colset 1 14 16 2}{...}
{p2col: }{space 2}{res:{txt:4.physact}{space 7}{txt:=} {space 3}.3034808 {txt:(mean)}}{p_end}
{p2colreset}{...}
{txt}{p2colset 1 14 16 2}{...}
{p2col: }{space 2}{res:{txt:5.physact}{space 7}{txt:=} {space 5}.11095 {txt:(mean)}}{p_end}
{p2colreset}{...}
{txt}{p2colset 1 14 16 2}{...}
{p2col: }{space 2}{res:{txt:age10}{space 11}{txt:=} {space 3}6.665228 {txt:(mean)}}{p_end}
{p2colreset}{...}
{txt}{p2colset 1 14 16 2}{...}
{p2col: }{space 2}{res:{txt:smoking}{space 9}{txt:=} {space 3}.1301668 {txt:(mean)}}{p_end}
{p2colreset}{...}
{txt}{p2colset 1 14 16 2}{...}
{p2col: }{space 2}{res:{txt:drnkspwk}{space 8}{txt:=} {space 3}1.357542 {txt:(mean)}}{p_end}
{p2colreset}{...}

{res}{txt}{hline 22}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 23}{c |}{col 35} Delta-method
{col 23}{c |}     Margin{col 35}   Std. Err.{col 47}      t{col 55}   P>|t|{col 63}     [95% Con{col 76}f. Interval]
{hline 22}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 14}physact {c |}
{space 4}much less active  {c |}{col 23}{res}{space 2} 30.80748{col 35}{space 2} .3726344{col 46}{space 1}   82.67{col 55}{space 3}0.000{col 63}{space 4}  30.0768{col 76}{space 3} 31.53815
{txt}somewhat less active  {c |}{col 23}{res}{space 2} 30.17946{col 35}{space 2} .2333813{col 46}{space 1}  129.31{col 55}{space 3}0.000{col 63}{space 4} 29.72184{col 76}{space 3} 30.63708
{txt}{space 5}about as active  {c |}{col 23}{res}{space 2} 29.00509{col 35}{space 2} .1715376{col 46}{space 1}  169.09{col 55}{space 3}0.000{col 63}{space 4} 28.66873{col 76}{space 3} 29.34144
{txt}somewhat more active  {c |}{col 23}{res}{space 2}  27.3171{col 35}{space 2}   .18039{col 46}{space 1}  151.43{col 55}{space 3}0.000{col 63}{space 4} 26.96339{col 76}{space 3} 27.67082
{txt}{space 4}much more active  {c |}{col 23}{res}{space 2} 26.70305{col 35}{space 2} .2978693{col 46}{space 1}   89.65{col 55}{space 3}0.000{col 63}{space 4} 26.11898{col 76}{space 3} 27.28712
{txt}{hline 22}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}{txt}
{com}. * verifiy results from last command
. * first generate mean values for predictors in estimation sample
. egen m_age10 = mean(age10) if e(sample)
{txt}(5 missing values generated)

{com}. egen m_smoking = mean(smoking) if e(sample)
{txt}(5 missing values generated)

{com}. egen m_drnkspwk = mean(drnkspwk) if e(sample)
{txt}(5 missing values generated)

{com}. gen z1 = _b[_cons] + _b[1.physact]*1 + _b[age10 ]*m_age10 + _b[smoking]*m_smoking + _b[drnkspwk]*m_drnkspwk if e(sample)
{txt}(5 missing values generated)

{com}. gen z2 = _b[_cons] + _b[2.physact]*1 + _b[age10 ]*m_age10 + _b[smoking]*m_smoking + _b[drnkspwk]*m_drnkspwk if e(sample)
{txt}(5 missing values generated)

{com}. gen z3 = _b[_cons] + _b[3.physact]*1 + _b[age10 ]*m_age10 + _b[smoking]*m_smoking + _b[drnkspwk]*m_drnkspwk if e(sample) 
{txt}(5 missing values generated)

{com}. gen z4 = _b[_cons] + _b[4.physact]*1 + _b[age10 ]*m_age10 + _b[smoking]*m_smoking + _b[drnkspwk]*m_drnkspwk if e(sample) 
{txt}(5 missing values generated)

{com}. gen z5 = _b[_cons] + _b[5.physact]*1 + _b[age10 ]*m_age10 + _b[smoking]*m_smoking + _b[drnkspwk]*m_drnkspwk if e(sample) 
{txt}(5 missing values generated)

{com}. summ z1 z2 z3 z4 z5

{txt}    Variable {c |}       Obs        Mean    Std. Dev.       Min        Max
{hline 13}{c +}{hline 56}
{space 10}z1 {c |}{res}      2758    30.80748           0   30.80748   30.80748
{txt}{space 10}z2 {c |}{res}      2758    30.17946           0   30.17946   30.17946
{txt}{space 10}z3 {c |}{res}      2758    29.00509           0   29.00509   29.00509
{txt}{space 10}z4 {c |}{res}      2758     27.3171           0    27.3171    27.3171
{txt}{space 10}z5 {c |}{res}      2758    26.70305           0   26.70305   26.70305
{txt}
{com}. * check that the differences between the adjusted marginal means 
. * (relative to the reference activity level) equal the estimated regression coefficients
. margins,  dydx(physact)
{res}
{txt}Average marginal effects{col 51}Number of obs{col 67}= {res}      2758
{txt}Model VCE{col 14}: {res}OLS

{txt}{p2colset 1 14 16 2}{...}
{p2col:Expression}:{space 1}{res:Linear prediction, predict()}{p_end}
{p2colreset}{...}
{txt}{p2colset 1 14 16 2}{...}
{p2col:dy/dx w.r.t.}:{space 1}{res:2.physact 3.physact 4.physact 5.physact}{p_end}
{p2colreset}{...}

{res}{txt}{hline 22}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 23}{c |}{col 35} Delta-method
{col 23}{c |}      dy/dx{col 35}   Std. Err.{col 47}      t{col 55}   P>|t|{col 63}     [95% Con{col 76}f. Interval]
{hline 22}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 14}physact {c |}
somewhat less active  {c |}{col 23}{res}{space 2}-.6280119{col 35}{space 2} .4376396{col 46}{space 1}   -1.43{col 55}{space 3}0.151{col 63}{space 4}-1.486147{col 76}{space 3} .2301235
{txt}{space 5}about as active  {c |}{col 23}{res}{space 2}-1.802389{col 35}{space 2} .4101722{col 46}{space 1}   -4.39{col 55}{space 3}0.000{col 63}{space 4}-2.606665{col 76}{space 3}-.9981121
{txt}somewhat more active  {c |}{col 23}{res}{space 2}-3.490371{col 35}{space 2} .4154996{col 46}{space 1}   -8.40{col 55}{space 3}0.000{col 63}{space 4}-4.305094{col 76}{space 3}-2.675648
{txt}{space 4}much more active  {c |}{col 23}{res}{space 2}-4.104422{col 35}{space 2} .4783847{col 46}{space 1}   -8.58{col 55}{space 3}0.000{col 63}{space 4}-5.042452{col 76}{space 3}-3.166392
{txt}{hline 22}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{p 0 6 0 87}Note: dy/dx for factor levels is the discrete change from the base level.{txt}{p_end}
{res}{txt}
{com}. 
. * test for heterogeneity
. testparm i.physact

{p 0 7}{space 1}{text:( 1)}{space 1} {res}2.physact = 0{p_end}
{p 0 7}{space 1}{text:( 2)}{space 1} 3.physact = 0{p_end}
{p 0 7}{space 1}{text:( 3)}{space 1} 4.physact = 0{p_end}
{p 0 7}{space 1}{text:( 4)}{space 1} 5.physact = 0{p_end}

{txt}       F(  4,  2750) ={res}   43.28
{txt}{col 13}Prob > F ={res}    0.0000
{txt}
{com}. * test for linear trend
. contrast q(1).physact, noeffects
{res}
{txt}Contrasts of marginal linear predictions

{txt}{p2colset 1 14 16 2}{...}
{p2col:Margins}:{space 1}{res:asbalanced}{p_end}
{p2colreset}{...}

{col 1}{text}{hline 13}{c TT}{hline 11}{hline 12}{hline 11}
{col 14}{text}{c |}         df{col 26}           F{col 38}        P>F
{col 1}{text}{hline 13}{c +}{hline 11}{hline 12}{hline 11}
{space 5}physact {col 14}{text}{c |}{result}{space 2}        1{col 26}{space 3}   120.97{col 38}{space 2}   0.0000
{col 14}{text}{c |}
{col 1}{text} Denominator{col 14}{c |}{result}{space 2}     2750
{col 1}{text}{hline 13}{c BT}{hline 11}{hline 12}{hline 11}

{com}. * test for departure from linear trend
. contrast q(2/4).physact, noeffects
{res}
{txt}Contrasts of marginal linear predictions

{txt}{p2colset 1 14 16 2}{...}
{p2col:Margins}:{space 1}{res:asbalanced}{p_end}
{p2colreset}{...}

{col 1}{text}{hline 13}{c TT}{hline 11}{hline 12}{hline 11}
{col 14}{text}{c |}         df{col 26}           F{col 38}        P>F
{col 1}{text}{hline 13}{c +}{hline 11}{hline 12}{hline 11}
{space 5}physact {c |}
(quadratic)  {col 14}{text}{c |}{result}{space 2}        1{col 26}{space 3}     0.21{col 38}{space 2}   0.6447
{txt}    (cubic)  {col 14}{text}{c |}{result}{space 2}        1{col 26}{space 3}     4.60{col 38}{space 2}   0.0321
{txt}  (quartic)  {col 14}{text}{c |}{result}{space 2}        1{col 26}{space 3}     0.91{col 38}{space 2}   0.3406
{col 1}{text}      Joint {col 14}{c |}{result}{space 2}        3{col 26}{space 3}     2.21{col 38}{space 2}   0.0852
{col 14}{text}{c |}
{col 1}{text} Denominator{col 14}{c |}{result}{space 2}     2750
{col 1}{text}{hline 13}{c BT}{hline 11}{hline 12}{hline 11}

{com}. 
. * models using log of creatinine level as outcome and predictor
. regress lncreat bmi age, eform("exp(beta)")

      {txt}Source {c |}       SS       df       MS              Number of obs ={res}    2756
{txt}{hline 13}{char +}{hline 30}           F(  2,  2753) ={res}   55.00
    {txt}   Model {char |} {res} 4.76569402     2  2.38284701           {txt}Prob > F      = {res} 0.0000
    {txt}Residual {char |} {res} 119.265116  2753  .043321873           {txt}R-squared     = {res} 0.0384
{txt}{hline 13}{char +}{hline 30}           Adj R-squared = {res} 0.0377
    {txt}   Total {char |} {res}  124.03081  2755  .045020258           {txt}Root MSE      = {res} .20814

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}     lncreat{col 14}{c |}  exp(beta){col 26}   Std. Err.{col 38}      t{col 46}   P>|t|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}bmi {c |}{col 14}{res}{space 2} 1.003308{col 26}{space 2} .0007303{col 37}{space 1}    4.54{col 46}{space 3}0.000{col 54}{space 4} 1.001877{col 67}{space 3} 1.004741
{txt}{space 9}age {c |}{col 14}{res}{space 2} 1.006093{col 26}{space 2} .0006076{col 37}{space 1}   10.06{col 46}{space 3}0.000{col 54}{space 4} 1.004902{col 67}{space 3} 1.007285
{txt}{space 7}_cons {c |}{col 14}{res}{space 2} .6405172{col 26}{space 2} .0309547{col 37}{space 1}   -9.22{col 46}{space 3}0.000{col 54}{space 4} .5826076{col 67}{space 3}  .704183
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}{txt}
{com}. nlcom 100*(exp(_b[bmi])-1)

       {txt}_nl_1:  {res}100*(exp(_b[bmi])-1)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}     lncreat{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2}  .330835{col 26}{space 2} .0730259{col 37}{space 1}    4.53{col 46}{space 3}0.000{col 54}{space 4} .1877068{col 67}{space 3} .4739632
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. regress sbp lncreat age diabetes

      {txt}Source {c |}       SS       df       MS              Number of obs ={res}    2761
{txt}{hline 13}{char +}{hline 30}           F(  3,  2757) ={res}   61.70
    {txt}   Model {char |} {res} 62724.9665     3  20908.3222           {txt}Prob > F      = {res} 0.0000
    {txt}Residual {char |} {res} 934341.036  2757  338.897728           {txt}R-squared     = {res} 0.0629
{txt}{hline 13}{char +}{hline 30}           Adj R-squared = {res} 0.0619
    {txt}   Total {char |} {res} 997066.003  2760  361.255798           {txt}Root MSE      = {res} 18.409

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}         sbp{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      t{col 46}   P>|t|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 5}lncreat {c |}{col 14}{res}{space 2} 9.211717{col 26}{space 2} 1.682269{col 37}{space 1}    5.48{col 46}{space 3}0.000{col 54}{space 4} 5.913081{col 67}{space 3} 12.51035
{txt}{space 9}age {c |}{col 14}{res}{space 2}  .444083{col 26}{space 2} .0536661{col 37}{space 1}    8.27{col 46}{space 3}0.000{col 54}{space 4} .3388531{col 67}{space 3} .5493129
{txt}{space 4}diabetes {c |}{col 14}{res}{space 2} 6.426345{col 26}{space 2} .8007529{col 37}{space 1}    8.03{col 46}{space 3}0.000{col 54}{space 4} 4.856209{col 67}{space 3} 7.996481
{txt}{space 7}_cons {c |}{col 14}{res}{space 2} 103.2765{col 26}{space 2} 3.600996{col 37}{space 1}   28.68{col 46}{space 3}0.000{col 54}{space 4} 96.21558{col 67}{space 3} 110.3374
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}{txt}
{com}. nlcom _b[lncreat]*log(1.25)

       {txt}_nl_1:  {res}_b[lncreat]*log(1.25)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 1}         sbp{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} 2.055535{col 26}{space 2} .3753876{col 37}{space 1}    5.48{col 46}{space 3}0.000{col 54}{space 4} 1.319789{col 67}{space 3} 2.791281
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. 
. log close
      {txt}name:  {res}<unnamed>
       {txt}log:  {res}/Users/steve/Documents/teaching/c2015/biostat208/labs/lab3/lab3.smcl
  {txt}log type:  {res}smcl
 {txt}closed on:  {res}21 Jan 2015, 17:50:45
{txt}{.-}
{smcl}
{txt}{sf}{ul off}