1557 ET - Treasury yields end the week higher, even after the Treasury Department says it will double to $4 billion the size of each buyback operation targeting long-dated bonds, starting next month. Investors require higher yields in Treasury auctions, but demand is generally firm. PCE inflation is expected to tick higher and investors await Fed Chairman Warsh's Jackson Hole speech late next week. Oil rises 7% this week and the WSJ Dollar Index falls 1%. The 30-year yield rises 0.011 percentage point this week to 5.276%. This week, the 10-year adds 0.041 p.p. to 4.737% and the two-year rises 0.061 p.p. to 4.232%.